WorldWideScience

Sample records for access control transportation

  1. 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...

  2. 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.

  3. 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 ...

  4. Analysing Access Control Specifications

    DEFF Research Database (Denmark)

    Probst, Christian W.; Hansen, René Rydhof

    2009-01-01

    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...

  5. 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

  6. Accessibility, land use and transport. Accessibility evaluation of land-use and transport developments and policy strategies

    NARCIS (Netherlands)

    Geurs, Karst Teunis

    2006-01-01

    How can accessibility be defined? How useful are different accessibility approaches in evaluating land-use and transport policy strategies? How can the economic benefits associated with accessibility changes be measured? What are the accessibility benefits of having a public transport service availa

  7. 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

  8. Towards Trusted Network Access Control

    Science.gov (United States)

    Bente, Ingo; von Helden, Josef

    Network Access Control (NAC) solutions promise to significantly increase the security level of modern networks. In short, they allow to measure the integrity state of an endpoint that tries to get access to the network. Based upon the measurement results, which are compared to a defined NAC policy, access to the network can be allowed or denied. One problem of all currently available NAC solutions is referred to as the “lying endpoint” problem. Normally, special software components are responsible for gathering the relevant integrity information on the endpoint. If an attacker modifies those software components, an endpoint can lie about its current integrity state. Therefore, endpoints which are not compliant to the defined NAC policy can get access to the network. Those endpoints must be considered as potential threat. This paper summarizes a possible solution for the lying endpoint problem based upon the specifications of the Trusted Computing Group (TCG) and the results of the two research projects TNC@ FHH and Turaya. The goal is to develop an open source, TNC compatible NAC solution with full TPM support within a new research project: tNAC.

  9. 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.

  10. 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.

  11. A Linux Implementation of Temporal Access Controls

    OpenAIRE

    Chiang, Ken; Nguyen, Thuy D.; Irvine, Cynthia E.

    2007-01-01

    Control of access to information based upon temporal attributes can add another dimension to access control. To demonstrate the feasibility of operating system level support for temporal access controls, the Time Interval File Protection System (TIFPS), a prototype of the Time Interval Access Control (TIAC) model, has been implemented by modifying Linux extended attributes to include temporal metadata associated both with files and users. The Linux Security Module was used to provide hooks fo...

  12. The concept of and factors affecting transport accessibility of seaports

    Directory of Open Access Journals (Sweden)

    Janusz Dąbrowski

    2012-03-01

    Full Text Available Transport accessibility of seaports is a frequently studied area in economic research. In practice, port operators and authorities use it to promote their services and compete in the market. Up to this day, theoretical basis of seaports transport accessibility has not been properly described. The article attempts to systematize and expend the knowledge in this field. New definitions of transport availability from wider and narrower perspectives were suggested; different types of accessibility and their mutual relations were explained. These ideas were complemented by introducing classification of factors affecting transport accessibility of seaports.

  13. 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.

  14. Random Access Game and Medium Access Control Design

    OpenAIRE

    Chen, Lijun; Low, Steven H.; Doyle, John C.

    2010-01-01

    Motivated partially by a control-theoretic viewpoint, we propose a game-theoretic model, called random access game, for contention control. We characterize Nash equilibria of random access games, study their dynamics, and propose distributed algorithms (strategy evolutions) to achieve Nash equilibria. This provides a general analytical framework that is capable of modeling a large class of system-wide quality-of-service (QoS) models via the specification of per-node util...

  15. An electronically controlled automatic security access gate

    OpenAIRE

    Jonathan A. Enokela; Michael N. TYOWUAH

    2014-01-01

    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 ...

  16. Evaluation of file access control implementations

    OpenAIRE

    Madar, Fatima Ali

    2005-01-01

    This thesis discusses two implementations of file access controls: the UNIX Permissions (UP) and the Access Control List (ACL). We will evaluate advantages and weaknesses in these two implementations. The criteria of evaluation are usefulness, security and manageability. The level of usefulness of systems was measured by evaluating user-surveys. The level of security was measured by comparing the implementations against well-established file access control models concerning privacy, inte...

  17. Access control system for ISABELLE

    International Nuclear Information System (INIS)

    An access system based on the one now in operation at the CERN ISR is recommended. Access doors would presumably be located at the entrances to the utility tunnels connecting the support buildings with the ring. Persons requesting access would insert an identity card into a scanner to activate the system. The request would be autologged, the keybank adjacent to the door would be unlocked and ISABELLE operations would be notified. The operator would then select the door, activating a TV-audio link. The person requesting entry would draw a key from the bank, show it and his film badge to the operator who would enable the door release

  18. Accessibility of cysteine residues in a cytoplasmic loop of CitS of Klebsiella pneumoniae is controlled by the catalytic state of the transporter

    NARCIS (Netherlands)

    Sobczak, [No Value; Lolkema, JS; Sobczak, Iwona

    2003-01-01

    The citrate transporter CAS of Klebsiella pneumoniae is a secondary transporter that transports citrate in symport with two sodium ions and one proton. Treatment of CAS with the alkylating, agent N-ethylmaleimide resulted in a complete loss of transport activity. Treatment of mutant proteins in whic

  19. Access control and service-oriented architectures

    NARCIS (Netherlands)

    Leune, C.J.

    2007-01-01

    Access Control and Service-Oriented Architectures" investigates in which way logical access control can be achieved effectively, in particular in highly dynamic environments such as service-oriented architectures (SOA's). The author combines state-of-the-art best-practice and projects these onto the

  20. 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…

  1. Formal Description of Trust-based Access Control

    Science.gov (United States)

    Xiaoning, Ma

    Different from traditional access control technologies, such as discretionary access control, mandatory access control, role-based access control, trust-based access control can solve the problem of uncertainty, risk and vulnerability coming from authorization. In this paper, strict definition and formal description of trust-based access control is defined.

  2. 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...

  3. 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...

  4. GIS model to evaluate the accessibility to major transport ways

    OpenAIRE

    Antonio Tache; Oana Popescu

    2015-01-01

    In order to ensure a balanced accessibility to major transport ways, supporting spatial development and economic growth, a GIS model to assess accessibility it was proposed. The model is measuring the average cost of travel (by car, usually) from a point to a predetermined number of destinations measured in units of time (minutes). Using the ARCGIS Spatial Analyst module, accessibility territorial indicators were calculated and presented as cartograms and maps that are outlining the accessibi...

  5. Disk access controller for Multi 8 computer

    International Nuclear Information System (INIS)

    After having presented the initial characteristics and weaknesses of the software provided for the control of a memory disk coupled with a Multi 8 computer, the author reports the development and improvement of this controller software. He presents the different constitutive parts of the computer and the operation of the disk coupling and of the direct access to memory. He reports the development of the disk access controller: software organisation, loader, subprograms and statements

  6. Modelling Access Control For Healthcare Information Systems

    OpenAIRE

    Ferreira, Ana; Chadwick, David W; Antunes, Luis

    2007-01-01

    The widening use of Information Systems, which allow the collection, extraction, storage, management and search of information, is increasing the need for information security. After a user is successfully identified and authenticated to a system, he needs to be authorised to access the resources he/she requested. Access control is part of this last process that checks if a user can access those resources. This is particularly important in the healthcare environment where there is the need to...

  7. 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

  8. Traveling Towards Disease: Transportation Barriers to Health Care Access

    OpenAIRE

    Syed, Samina T.; Gerber, Ben S.; Sharp, Lisa K.

    2013-01-01

    Transportation barriers are often cited as barriers to healthcare access. Transportation barriers lead to rescheduled or missed appointments, delayed care, and missed or delayed medication use. These consequences may lead to poorer management of chronic illness and thus poorer health outcomes. However, the significance of these barriers is uncertain based on existing literature due to wide variability in both study populations and transportation barrier measures. The authors sought to synthes...

  9. Reported Design Processes for Accessibility in Rail Transport

    DEFF Research Database (Denmark)

    Herriott, Richard; Cook, Sharon

    2014-01-01

    Accessibility is a fundamental requirement in public transport (PT) yet there exists little research on design for accessibility or inclusive design (ID) in this area. This paper sets out to discover what methods are used in the rail sector to achieve accessibility goals and to examine how far......). The research found that the role of users in the design process of manufacturers was limited and that compliance with industry standards was the dominant means to achieving accessibility goals. Design consultancies were willing to apply more user-centred design if the client requested it. Where operators were...

  10. Operational Control of Internal Transport

    NARCIS (Netherlands)

    J.R. van der Meer (Robert)

    2000-01-01

    textabstractOperational Control of Internal Transport considers the control of guided vehicles in vehicle-based internal transport systems found in facilities such as warehouses, production plants, distribution centers and transshipment terminals. The author's interest of research having direct use

  11. 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

  12. Access control issues in social networks

    OpenAIRE

    Carreras Coch, Anna; Rodríguez Luna, Eva; Delgado Mercè, Jaime; Maroñas Borras, Xavier

    2010-01-01

    Social Networks, as the main axis of Web 2.0, are creating a number of interesting challenges to the research and standardisation communities. In this paper, we analyse the current and future use of access control policies in Social Networks. Subsequently, two main issues are addressed: the interoperability amongst systems using different policy languages and the lack of elements in the existing policy languages when trying to express Social Networks’ access control. In part...

  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. Nanoengineered membranes for controlled transport

    Science.gov (United States)

    Doktycz, Mitchel J [Oak Ridge, TN; Simpson, Michael L [Knoxville, TN; McKnight, Timothy E [Greenback, TN; Melechko, Anatoli V [Oak Ridge, TN; Lowndes, Douglas H [Knoxville, TN; Guillorn, Michael A [Knoxville, TN; Merkulov, Vladimir I [Oak Ridge, TN

    2010-01-05

    A nanoengineered membrane for controlling material transport (e.g., molecular transport) is disclosed. The membrane includes a substrate, a cover definining a material transport channel between the substrate and the cover, and a plurality of fibers positioned in the channel and connected to an extending away from a surface of the substrate. The fibers are aligned perpendicular to the surface of the substrate, and have a width of 100 nanometers or less. The diffusion limits for material transport are controlled by the separation of the fibers. In one embodiment, chemical derivitization of carbon fibers may be undertaken to further affect the diffusion limits or affect selective permeability or facilitated transport. For example, a coating can be applied to at least a portion of the fibers. In another embodiment, individually addressable carbon nanofibers can be integrated with the membrane to provide an electrical driving force for material transport.

  15. Access Control Management for SCADA Systems

    Science.gov (United States)

    Hong, Seng-Phil; Ahn, Gail-Joon; Xu, Wenjuan

    The information technology revolution has transformed all aspects of our society including critical infrastructures and led a significant shift from their old and disparate business models based on proprietary and legacy environments to more open and consolidated ones. Supervisory Control and Data Acquisition (SCADA) systems have been widely used not only for industrial processes but also for some experimental facilities. Due to the nature of open environments, managing SCADA systems should meet various security requirements since system administrators need to deal with a large number of entities and functions involved in critical infrastructures. In this paper, we identify necessary access control requirements in SCADA systems and articulate access control policies for the simulated SCADA systems. We also attempt to analyze and realize those requirements and policies in the context of role-based access control that is suitable for simplifying administrative tasks in large scale enterprises.

  16. Performance estimates for personnel access control systems

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, R. G.

    1980-10-01

    Current performance estimates for personnel access control systems use estimates of Type I and Type II verification errors. A system performance equation which addresses normal operation, the insider, and outside adversary attack is developed. Examination of this equation reveals the inadequacy of classical Type I and II error evaluations which require detailed knowledge of the adversary threat scenario for each specific installation. Consequently, new performance measures which are consistent with the performance equation and independent of the threat are developed as an aid in selecting personnel access control systems.

  17. 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,

  18. An Access Definition and Query Language : Towards a Unified Access Control Model

    OpenAIRE

    Sonnenbichler, Andreas

    2013-01-01

    In this work we suggest a meta access control model emulating established access control models by configuration and offering enhanced features like the delegation of rights, ego-centered roles, and decentralized administration. The suggested meta access control model is named \\'\\'Access Definition and Query Language\\'\\' (ADQL). ADQL is represented by a formal, context-free grammar allowing to express the targeted access control model, policies, facts, and access queries as a formal language.

  19. 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

  20. 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.

  1. 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.

  2. 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...

  3. LANSCE personnel access control system (PACS)

    International Nuclear Information System (INIS)

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. The Personnel Access Control System (PACS) is a component of the RSS that is designed to prevent personnel access to areas where prompt radiation is a hazard. PACS was designed to replace several older personnel safety systems (PSS) with a single modem unified design. Lessons learned from the operation over the last 20 years were incorporated into a redundant sensor, single-point failure safe, fault tolerant, and tamper-resistant system that prevents access to the beam areas by controlling the access keys and beam stoppers. PACS uses a layered philosophy to the physical and electronic design. The most critical assemblies are battery backed up, relay logic circuits; less critical devices use Programmable Logic Controllers (PLCs) for timing functions and communications. Outside reviewers have reviewed the operational safety of the design. The design philosophy, lessons learned, hardware design, software design, operation, and limitations of the device are described

  4. 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.

  5. 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.

  6. Feedback control of colloidal transport

    OpenAIRE

    Gernert, R.; Loos, S. A. M.; Lichtner, K.; Klapp, S. H. L.

    2015-01-01

    We review recent work on feedback control of one-dimensional colloidal systems, both with instantaneous feedback and with time delay. The feedback schemes are based on measurement of the average particle position, a natural control target for an ensemble of colloidal particles, and the systems are investigated via the Fokker-Planck equation for overdamped Brownian particles. Topics include the reversal of current and the emergence of current oscillations, transport in ratchet systems, and the...

  7. 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.

  8. Studying Media Access andControl Protocols

    OpenAIRE

    Mohammed, Alalelddin Fuad Yousif

    2010-01-01

    This thesis project’s goal is to enable undergraduate students to gain insight into media access and control protocols based upon carrying out laboratory experiments. The educational goal is to de-mystifying radio and other link and physical layer communication technologies as the students can follow packets from the higher layers down through the physical layer and back up again. The thesis fills the gap between the existing documentation for the Universal Software Radio Peripheral (USRP) re...

  9. External access to ALICE controls conditions data

    Science.gov (United States)

    Jadlovský, J.; Jadlovská, A.; Sarnovský, J.; Jajčišin, Š.; Čopík, M.; Jadlovská, S.; Papcun, P.; Bielek, R.; Čerkala, J.; Kopčík, M.; Chochula, P.; Augustinus, A.

    2014-06-01

    ALICE Controls data produced by commercial SCADA system WINCCOA is stored in ORACLE database on the private experiment network. The SCADA system allows for basic access and processing of the historical data. More advanced analysis requires tools like ROOT and needs therefore a separate access method to the archives. The present scenario expects that detector experts create simple WINCCOA scripts, which retrieves and stores data in a form usable for further studies. This relatively simple procedure generates a lot of administrative overhead - users have to request the data, experts needed to run the script, the results have to be exported outside of the experiment network. The new mechanism profits from database replica, which is running on the CERN campus network. Access to this database is not restricted and there is no risk of generating a heavy load affecting the operation of the experiment. The developed tools presented in this paper allow for access to this data. The users can use web-based tools to generate the requests, consisting of the data identifiers and period of time of interest. The administrators maintain full control over the data - an authorization and authentication mechanism helps to assign privileges to selected users and restrict access to certain groups of data. Advanced caching mechanism allows the user to profit from the presence of already processed data sets. This feature significantly reduces the time required for debugging as the retrieval of raw data can last tens of minutes. A highly configurable client allows for information retrieval bypassing the interactive interface. This method is for example used by ALICE Offline to extract operational conditions after a run is completed. Last but not least, the software can be easily adopted to any underlying database structure and is therefore not limited to WINCCOA.

  10. 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

  11. Collaborative Access Control For Critical Infrastructures

    Science.gov (United States)

    Baina, Amine; El Kalam, Anas Abou; Deswarte, Yves; Kaaniche, Mohamed

    A critical infrastructure (CI) can fail with various degrees of severity due to physical and logical vulnerabilities. Since many interdependencies exist between CIs, failures can have dramatic consequences on the entire infrastructure. This paper focuses on threats that affect information and communication systems that constitute the critical information infrastructure (CII). A new collaborative access control framework called PolyOrBAC is proposed to address security problems that are specific to CIIs. The framework offers each organization participating in a CII the ability to collaborate with other organizations while maintaining control of its resources and internal security policy. The approach is demonstrated on a practical scenario involving the electrical power grid.

  12. Accessibility of a Destination-Based Transportation System: A Large Airport Study

    Institute of Scientific and Technical Information of China (English)

    SHI Jing; YING Xiwen

    2008-01-01

    The accessibility of a destination-based transportation system is defined to quantify the perform-ance of transportation systems which access a distinct destination. The access cost is used to reflect the utility of the transportation system including the fatigue and inconvenience in the total cost. The cost is quan-tified by two coefficients which represent the different characteristics of various people. The average cost and the income-relative accessibility are used to describe various aspects of the accessibility and to evaluate the accessibility of a destination-based system. A case study uses data from the Kunming transpor-tation system to evaluate the accessibility of the present city airport. The calibrated coefficients are then used to evaluate the transportation system to the new Kunming international airport. The results show that this transportation accessibility evaluation can be combined with transportation planning to study transporta-tion sub-systems.

  13. The alternating access mechanism of transport as observed in the sodium-hydantoin transporter Mhp1

    International Nuclear Information System (INIS)

    Crystal structures of a membrane protein transporter in three different conformational states provide insights into the transport mechanism. Secondary active transporters move molecules across cell membranes by coupling this process to the energetically favourable downhill movement of ions or protons along an electrochemical gradient. They function by the alternating access model of transport in which, through conformational changes, the substrate binding site alternately faces either side of the membrane. Owing to the difficulties in obtaining the crystal structure of a single transporter in different conformational states, relatively little structural information is known to explain how this process occurs. Here, the structure of the sodium-benzylhydantoin transporter, Mhp1, from Microbacterium liquefaciens, has been determined in three conformational states; from this a mechanism is proposed for switching from the outward-facing open conformation through an occluded structure to the inward-facing open state

  14. 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.

  15. Attributes Enhanced Role-Based Access Control Model

    DEFF Research Database (Denmark)

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

    2015-01-01

    Attribute-based access control (ABAC) and role-based access control (RBAC) are currently the two most popular access control models. Yet, they both have known limitations and offer features com- plimentary to each other. Due to this fact, integration of RBAC and ABAC has recently emerged as an im......Attribute-based access control (ABAC) and role-based access control (RBAC) are currently the two most popular access control models. Yet, they both have known limitations and offer features com- plimentary to each other. Due to this fact, integration of RBAC and ABAC has recently emerged...

  16. 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.

  17. 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...

  18. Perceived Accessibility of Public Transport as a Potential Indicator of Social Inclusion

    OpenAIRE

    Katrin Lättman; Margareta Friman; Olsson, Lars E.

    2016-01-01

    Perceived accessibility has been acknowledged as an important aspect of transport policy since the 70s. Nevertheless, very few empirical studies have been conducted in this field. When aiming to improve social inclusion, by making sustainable transport modes accessible to all, it is important to understand the factors driving perceived accessibility. Unlike conventional accessibility measures, perceived accessibility focuses on the perceived possibilities and ease of engaging in preferred act...

  19. 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

  20. Laminar flow control for transport aircraft applications

    Science.gov (United States)

    Wagner, R. D.

    1986-01-01

    The incorporation of laminar flow control into transport aircraft is discussed. Design concepts for the wing surface panel of laminar flow control transport aircraft are described. The development of small amounts of laminar flow on small commercial transports with natural or hybrid flow control is examined. Techniques for eliminating the insect contamination problem in the leading-edge region are proposed.

  1. 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.

  2. How Does Car Parking Availability and Public Transport Accessibility Influence Work-Related Travel Behaviors?

    Directory of Open Access Journals (Sweden)

    Grant M. Schofield

    2010-02-01

    Full Text Available This study investigated the relationships between car parking, public transport, travel behaviors, and health outcomes for adults (n = 1,188 traveling to a worksite. Public transport was used for 12.1% of the work-related commute. Those who had higher levels of walking, no worksite car park access, lived proximal to a public transport stop, had limited automobile availability, traveled to the main business district, perceived public transport as accessible, or did not have company car access were more likely to use public transportation. Accordingly, proximal residential transit stops and restrictions for company car accessibility and parking at the worksite are needed.

  3. Accessible Tourism : A Study of accessibility in Hotel Chains,Public Transport and Ferry Companies in Helsinki

    OpenAIRE

    Khatri, Kumar; Shrestha, Rajkumar; Mahat, Ujjwal

    2012-01-01

    This Bachelor’s thesis was prepared for the fulfillment of the educational standard of Laurea University of Applied Sciences. This thesis is aimed to achieve a main goal which is to explore accessible service and product with its environment into hotel chains, public transportation and ferry companies in Helsinki. In addition, this thesis describes the current accessibility situation of hotel chains, public transportation and two ferry companies in Helsinki. The empirical study material ...

  4. Verifying Resource Access Control on Mobile Interactive Devices

    OpenAIRE

    Besson, Frédéric; Dufay, Guillaume; Jensen, Thomas; Pichardie, David

    2010-01-01

    A model of resource access control is presented in which the access control to resources can employ user interaction to obtain the necessary permissions. This model is inspired by and improves on the Java security architecture used in Java-enabled mobile telephones. We extend the Java model to include access control permissions with multiplicities in order to allow to use a permission a certain number of times. We define a program model based on control flow graphs together with its operation...

  5. Perceived Accessibility of Public Transport as a Potential Indicator of Social Inclusion

    Directory of Open Access Journals (Sweden)

    Katrin Lättman

    2016-06-01

    Full Text Available Perceived accessibility has been acknowledged as an important aspect of transport policy since the 70s. Nevertheless, very few empirical studies have been conducted in this field. When aiming to improve social inclusion, by making sustainable transport modes accessible to all, it is important to understand the factors driving perceived accessibility. Unlike conventional accessibility measures, perceived accessibility focuses on the perceived possibilities and ease of engaging in preferred activities using different transport modes. We define perceived accessibility in terms of how easy it is to live a satisfactory life with the help of the transport system, which is not necessarily the same thing as the objective standard of the system. According to previous research, perceived accessibility varies with the subjectively-rated quality of the mode of transport. Thus, improvements in quality (e.g. trip planning, comfort, or safety increase the perceived accessibility and make life easier to live using the chosen mode of transport. This study (n=750 focuses on the perceived accessibility of public transport, captured using the Perceived Accessibility Scale PAC (Lättman, Olsson, & Friman, 2015. More specifically, this study aims to determine how level of quality affects the perceived accessibility in public transport. A Conditional Process Model shows that, in addition to quality, feeling safe and frequency of travel are important predictors of perceived accessibility. Furthermore, elderly and those in their thirties report a lower level of perceived accessibility to their day-to-day activities using public transport. The basic premise of this study is that subjective experiences may be as important as objective indicators when planning and designing for socially inclusive transport systems.

  6. A Formal Model of Access Control for Mobile Interactive Devices

    OpenAIRE

    Besson, Frédéric; Dufay, Guillaume; Jensen, Thomas

    2006-01-01

    This paper presents an access control model for programming applications in which the access control to resources can employ user interaction to obtain the necessary permissions. This model is inspired by and improves on the Java security architecture used in Javaenabled mobile telephones. We consider access control permissions with multiplicities in order to allow to use a permission a certain number of times. An operational semantics of the model and a formal definition of what it means for...

  7. Performance analysis of multichannel medium access control algorithms for opportunistic spectrum access

    NARCIS (Netherlands)

    Pawelczak, P.; Pollin, S.; So, H.-S.W.; Bahai, A.R.S.; Prasad, R.V.; Hekmat, R.

    2009-01-01

    In this paper, different control channel (CC) implementations for multichannel medium access control (MAC) algorithms are compared and analyzed in the context of opportunistic spectrum access (OSA) as a function of spectrum-sensing performance and licensed user activity. The analysis is based on a d

  8. 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.

  9. 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

  10. 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...

  11. 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

  12. 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,

  13. 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…

  14. 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.

  15. Individual public transportation accessibility is positively associated with self-reported active commuting

    Directory of Open Access Journals (Sweden)

    Sune eDjurhuus

    2014-11-01

    Full Text Available Background: Active commuters have lower risk of chronic disease. Understanding which of the, to some extent, modifiable characteristics of public transportation that facilitate its use is thus important in a public health perspective. The aim of the study was to examine the association between individual public transportation accessibility and self-reported active commuting, and whether the associations varied with commute distance, age and gender. Methods: 28,928 commuters in the Capital Region of Denmark reported self-reported time spent either walking or cycling to work or study each day and the distance to work or study. Data were obtained from the Danish National Health Survey collected in February to April 2010. Individual accessibility by public transportation was calculated using a multimodal network in a GIS. Multilevel logistic regression was used to analyze the association between accessibility, expressed as access area, and being an active commuter.Results: Public transport accessibility area based on all stops within walking and cycling distance was positively associated with being an active commuter. Distance to work, age and gender modified the associations. Residing within 10 km commuting distance and in areas of high accessibility was associated with being an active commuter and meeting the recommendations of physical activity. For the respondents above 29 years, Individual public transportation accessibility was positively associated with being an active commuter. Women having high accessibility had significantly higher odds of being an active commuter compared to having a low accessibility. For men the associations were insignificant.Conclusions: This study extends the knowledge about the driving forces of using public transportation for commuting by examining the individual public transportation accessibility. Findings suggest that transportation accessibility supports active commuting and planning of improved public transit

  16. Providing access to a Public Transport Schedule system for Smart Phone Clients

    OpenAIRE

    Hameseder, Katrin

    2010-01-01

    This master thesis was conducted during an internship at HBT GmbH with the purpose of providing access to an existing public transport schedule system in Hamburg (Germany) for smart phone clients. A state-of-the-art literature review and an evaluation of an existing SOAP (Simple Object Access Protocol) based web service to access public transport schedule information were conducted to identify the drawbacks of the existing interface with respect to the limitations and characteristics of smart...

  17. 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.

  18. 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.

  19. Distributed Access Control Policies for Spectrum Sharing

    OpenAIRE

    Baldini, Gianmarco; NAI-FOVINO Igor; Trombetta, Alberto; Braghin, Stefano

    2012-01-01

    Cognitive Radio (CR) is a novel wireless communication technology that allows for adaptive configuration of the reception parameters of a terminal, based on the information collected from the environment. Cognitive radio (CR) technology can be used in innovative spectrum management approaches like spectrum sharing, where radio frequency spectral bands can be shared among various users through a dynamic exclusive-use spectrum access model. Spectrum sharing can be applied to various...

  20. The Time Between: Continuously-defined accessibility functions for schedule-based transportation systems

    OpenAIRE

    Paul Anderson; Andrew Owen; David Levinson

    2012-01-01

    Accessibility is traditionally considered to be a property of a point or region in space, and to be invariant over time (or at least over some computationally convenient time interval). How- ever, a locations accessibility can vary over time on a wide range of scales. This temporal variation is especially significant for schedule-based transportation systems. Current measures of accessibility generally reflect the accessibility only at points in time corresponding to the departures of one or ...

  1. Effects of Job Accessibility Improved by Public Transport System: Natural Experimental Evidence from the Copenhagen Metro

    DEFF Research Database (Denmark)

    Pons Rotger, Gabriel Angel; Nielsen, Thomas Alexander Sick

    2015-01-01

    This study examines the effect of accessibility to urban jobs via a public transport system on individual earnings and commuting behaviour. The effect of improved public transport based accessibility on these outcomes is determined by exploiting the exogenous variation in access to a public rail...... and Metro system resulting from the construction of a new terminal Metro station connecting southern townships to Copenhagen city centre. The results show that public transport based job accessibility has a positive and permanent effect on individual earnings. The increase in earnings is associated...... with a change in commuting patterns as the improved access to public transport facilitates a shift from employment within the township to better paid jobs in the city centre, as well as in other suburbs of the Copenhagen Metropolitan area...

  2. Robust access control framework for mobile cloud computing network

    OpenAIRE

    Li, F; Rahulamathavan, Y.; Conti, M.; Rajarajan, M.

    2015-01-01

    Unified communications has enabled seamless data sharing between multiple devices running on various platforms. Traditionally, organizations use local servers to store data and employees access the data using desktops with predefined security policies. In the era of unified communications, employees exploit the advantages of smart devices and 4G wireless technology to access the data from anywhere and anytime. Security protocols such as access control designed for traditional setup are not su...

  3. 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.

  4. 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)

  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. 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.

  7. 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.

  8. 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

  9. 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.

  10. A United Access Control Model for Systems in Collaborative Commerce

    OpenAIRE

    Ruo-Fei Han; Hou-Xiang Wang; Qian Xiao; Xiao-Pei Jing; Hui Li

    2009-01-01

    The latest researches on access control model are dramatically different from conventional ones. Nowadays, most attention is paid to accessing across organizational boundaries. So, how to identify the applicant and determine authorization with limited information; how to express and exchange control rules expediently; how to protect confidential information and enhance collaboration simultaneously, are the most concerned problems. However, for large commercial organizations, a fine management...

  11. 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.

  12. 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).

  13. 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.

  14. The Association between Access to Public Transportation and Self-Reported Active Commuting

    Directory of Open Access Journals (Sweden)

    Sune Djurhuus

    2014-12-01

    Full Text Available Active commuting provides routine-based regular physical activity which can reduce the risk of chronic diseases. Using public transportation involves some walking or cycling to a transit stop, transfers and a walk to the end location and users of public transportation have been found to accumulate more moderate physical activity than non-users. Understanding how public transportation characteristics are associated with active transportation is thus important from a public health perspective. This study examines the associations between objective measures of access to public transportation and self-reported active commuting. Self-reported time spent either walking or cycling commuting each day and the distance to workplace were obtained for adults aged 16 to 65 in the Danish National Health Survey 2010 (n = 28,928. Access to public transportation measures were computed by combining GIS-based road network distances from home address to public transit stops an integrating their service level. Multilevel logistic regression was used to examine the association between access to public transportation measures and active commuting. Distance to bus stop, density of bus stops, and number of transport modes were all positively associated with being an active commuter and with meeting recommendations of physical activity. No significant association was found between bus services at the nearest stop and active commuting. The results highlight the importance of including detailed measurements of access to public transit in order to identify the characteristics that facilitate the use of public transportation and active commuting.

  15. Hopping control channel MAC protocol for opportunistic spectrum access networks

    Institute of Scientific and Technical Information of China (English)

    FU Jing-tuan; JI Hong; MAO Xu

    2010-01-01

    Opportunistic spectrum access (OSA) is considered as a promising approach to mitigate spectrum scarcity by allowing unlicensed users to exploit spectrum opportunities in licensed frequency bands. Derived from the existing channel-hopping multiple access (CHMA) protocol,we introduce a hopping control channel medium access control (MAC) protocol in the context of OSA networks. In our proposed protocol,all nodes in the network follow a common channel-hopping sequence; every frequency channel can be used as control channel and data channel. Considering primary users' occupancy of the channel,we use a primary user (PU) detection model to calculate the channel availability for unlicensed users' access. Then,a discrete Markov chain analytical model is applied to describe the channel states and deduce the system throughput. Through simulation,we present numerical results to demonstrate the throughput performance of our protocol and thus validate our work.

  16. 25 CFR 170.813 - When can access to IRR transportation facilities be restricted?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false When can access to IRR transportation facilities be restricted? 170.813 Section 170.813 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER INDIAN RESERVATION ROADS PROGRAM BIA Road Maintenance § 170.813 When can access to...

  17. Multi terabits/s optical access transport technologies

    Science.gov (United States)

    Binh, Le Nguyen; Wang Tao, Thomas; Livshits, Daniil; Gubenko, Alexey; Karinou, Fotini; Liu Ning, Gordon; Shkolnik, Alexey

    2016-02-01

    Tremendous efforts have been developed for multi-Tbps over ultra-long distance and metro and access optical networks. With the exponential increase demand on data transmission, storage and serving, especially the 5G wireless access scenarios, the optical Internet networking has evolved to data-center based optical networks pressuring on novel and economical access transmission systems. This paper reports (1) Experimental platforms and transmission techniques employing band-limited optical components operating at 10G for 100G based at 28G baud. Advanced modulation formats such as PAM-4, DMT, duo-binary etc are reported and their advantages and disadvantages are analyzed so as to achieve multi-Tbps optical transmission systems for access inter- and intra- data-centered-based networks; (2) Integrated multi-Tbps combining comb laser sources and micro-ring modulators meeting the required performance for access systems are reported. Ten-sub-carrier quantum dot com lasers are employed in association with wideband optical intensity modulators to demonstrate the feasibility of such sources and integrated micro-ring modulators acting as a combined function of demultiplexing/multiplexing and modulation, hence compactness and economy scale. Under the use of multi-level modulation and direct detection at 56 GBd an aggregate of higher than 2Tbps and even 3Tbps can be achieved by interleaved two comb lasers of 16 sub-carrier lines; (3) Finally the fundamental designs of ultra-compacts flexible filters and switching integrated components based on Si photonics for multi Tera-bps active interconnection are presented. Experimental results on multi-channels transmissions and performances of optical switching matrices and effects on that of data channels are proposed.

  18. Face recognition in controlled access points

    OpenAIRE

    Mur Escartín, Olga

    2009-01-01

    The thesis consist in the study and evaluation of different methods for face recognition. The final objective is to select the most suitable techniques for face detection and recognition. Some of these techniques will be intergrated in a real time demontrator which will be a preliminary prototype that will have to work in controlled conditions (for ilumination and pose) and with reduced databases. The demonstrator will be done in Matlab and the main image acquisition rotines and face detectio...

  19. A United Access Control Model for Systems in Collaborative Commerce

    Directory of Open Access Journals (Sweden)

    Ruo-Fei Han

    2009-06-01

    Full Text Available The latest researches on access control model are dramatically different from conventional ones. Nowadays, most attention is paid to accessing across organizational boundaries. So, how to identify the applicant and determine authorization with limited information; how to express and exchange control rules expediently; how to protect confidential information and enhance collaboration simultaneously, are the most concerned problems. However, for large commercial organizations, a fine management of internal functions is of the same importance as external service management. It is very troublesome to control authorizations merely with attributes and composition of policies introduced from attribute-based access control (ABAC. So, we introduce a united access control model for systems in collaborative commerce, combining the advantages of conventional role-based access control (RBAC, task-based authentication control (TBAC and that of recent ABAC and automated trust negotiation (ATN. Innovational ideas in the model are analyzed, and the implement architecture is discussed. The paper concludes with a summary of the united model’s benefits and future work.

  20. Role Based Access Control System in the ATLAS Experiment

    CERN Document Server

    Valsan, M L; The ATLAS collaboration; Lehmann Miotto, G; Scannicchio, D A; Schlenker, S; Filimonov, V; Khomoutnikov, V; Dumitru, I; Zaytsev, A S; Korol, A A; Bogdantchikov, A; Avolio, G; Caramarcu, C; Ballestrero, S; Darlea, G L; Twomey, M; Bujor, F

    2010-01-01

    The complexity of the ATLAS experiment motivated the deployment of an integrated Access Control System in order to guarantee safe and optimal access for a large number of users to the various software and hardware resources. Such an integrated system was foreseen since the design of the infrastructure and is now central to the operations model. In order to cope with the ever growing needs of restricting access to all resources used within the experiment, the Roles Based Access Control (RBAC) previously developed has been extended and improved. The paper starts with a short presentation of the RBAC design, implementation and the changes made to the system to allow the management and usage of roles to control access to the vast and diverse set of resources. The paper continues with a detailed description of the integration across all areas of the system: local Linux and Windows nodes in the ATLAS Control Network (ATCN), the Linux application gateways offering remote access inside ATCN, the Windows Terminal Serv...

  1. Role Based Access Control system in the ATLAS experiment

    CERN Document Server

    Valsan, M L; The ATLAS collaboration; Lehmann Miotto, G; Scannicchio, D A; Schlenker, S; Filimonov, V; Khomoutnikov, V; Dumitru, I; Zaytsev, A S; Korol, A A; Bogdantchikov, A; Caramarcu, C; Ballestrero, S; Darlea, G L; Twomey, M; Bujor, F; Avolio, G

    2011-01-01

    The complexity of the ATLAS experiment motivated the deployment of an integrated Access Control System in order to guarantee safe and optimal access for a large number of users to the various software and hardware resources. Such an integrated system was foreseen since the design of the infrastructure and is now central to the operations model. In order to cope with the ever growing needs of restricting access to all resources used within the experiment, the Roles Based Access Control (RBAC) previously developed has been extended and improved. The paper starts with a short presentation of the RBAC design, implementation and the changes made to the system to allow the management and usage of roles to control access to the vast and diverse set of resources. The paper continues with a detailed description of the integration across all areas of the system: local Linux and Windows nodes in the ATLAS Control Network (ATCN), the Linux application gateways offering remote access inside ATCN, the Windows Terminal Serv...

  2. 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.

  3. Control with a random access protocol and packet dropouts

    Science.gov (United States)

    Wang, Liyuan; Guo, Ge

    2016-08-01

    This paper investigates networked control systems whose actuators communicate with the controller via a limited number of unreliable channels. The access to the channels is decided by a so-called group random access protocol, which is modelled as a binary Markov sequence. Data packet dropouts in the channels are modelled as independent Bernoulli processes. For such systems, a systematic characterisation for controller synthesis is established and stated in terms of the transition probabilities of the Markov protocol and the packet dropout probabilities. The results are illustrated via a numerical example.

  4. 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.

  5. Public information: control, secret and right of access

    OpenAIRE

    Carmem Lúcia Batista

    2012-01-01

    Recently, in November 2011, it was published the law on access to public information, legal and historic mark in the struggle for human rights in Brazil. This achievement is the result of a process marked by denial of access to public archives, as it was the case of the Araguaia Guerrilla, valuing the culture of secrecy, abuse of power and relations between public and private in Brazil. Thus, the aim of this paper is to present a brief history about the control of access to public information...

  6. User Behavior Trust Based Cloud Computing Access Control Model

    OpenAIRE

    Jiangcheng, Qin

    2016-01-01

    Context. With the development of computer software, hardware, and communication technologies, a new type of human-centered computing model, called Cloud Computing (CC) has been established as a commercial computer network service. However, the openness of CC brings huge security challenge to the identity-based access control system, as it not able to effectively prevent malicious users accessing; information security problems, system stability problems, and also the trust issues between cloud...

  7. Open Platform Strategies and Innovation: Granting Access vs. Devolving Control

    OpenAIRE

    Kevin Boudreau

    2010-01-01

    This paper studies two fundamentally distinct approaches to opening a technology platform and their different impacts on innovation. One approach is to grant access to a platform and thereby open up markets for complementary components around the platform. Another approach is to give up control over the platform itself. Using data on 21 handheld computing systems (1990-2004), I find that granting greater levels of access to independent hardware developer firms produces up to a fivefold accele...

  8. Law-Aware Access Control and its Information Model

    OpenAIRE

    Stieghahn, Michael; Engel, Thomas

    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 exa...

  9. 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.

  10. 49 CFR 176.89 - Control of transport vehicles.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Control of transport vehicles. 176.89 Section 176... Special Requirements for Transport Vehicles Loaded With Hazardous Materials and Transported on Board Ferry Vessels § 176.89 Control of transport vehicles. (a) A transport vehicle containing hazardous materials...

  11. Hybrid Predictive Control for Dynamic Transport Problems

    CERN Document Server

    Núñez, Alfredo A; Cortés, Cristián E

    2013-01-01

    Hybrid Predictive Control for Dynamic Transport Problems develops methods for the design of predictive control strategies for nonlinear-dynamic hybrid discrete-/continuous-variable systems. The methodology is designed for real-time applications, particularly the study of dynamic transport systems. Operational and service policies are considered, as well as cost reduction. The control structure is based on a sound definition of the key variables and their evolution. A flexible objective function able to capture the predictive behaviour of the system variables is described. Coupled with efficient algorithms, mainly drawn from the area of computational intelligence, this is shown to optimize performance indices for real-time applications. The framework of the proposed predictive control methodology is generic and, being able to solve nonlinear mixed-integer optimization problems dynamically, is readily extendable to other industrial processes. The main topics of this book are: ●hybrid predictive control (HPC) ...

  12. Space Transportation Systems Life Cycle Cost Assessment and Control

    Science.gov (United States)

    Robinson, John W.; Rhodes, Russell E.; Zapata, Edgar; Levack, Daniel J. H.; Donahue, Benjaamin B.; Knuth, William

    2008-01-01

    Civil and military applications of space transportation have been pursued for just over 50 years and there has been, and still is, a need for safe, dependable, affordable, and sustainable space transportation systems. Fully expendable and partially reusable space transportation systems have been developed and put in operation that have not adequately achieved this need. Access to space is technically achievable, but presently very expensive and will remain so until there is a breakthrough in the way we do business. Since 1991 the national Space Propulsion Synergy Team (SPST) has reviewed and assessed the lessons learned from the major U.S. space programs of the past decades focusing on what has been learned from the assessment and control of Life Cycle Cost (LCC) from these systems. This paper presents the results of a selected number of studies and analyses that have been conducted by the SPST addressing the need, as well as the solutions, for improvement in LCC. The major emphasis of the SPST processes is on developing the space transportation system requirements first (up front). These requirements must include both the usual system flight performance requirements and also the system functional requirements, including the infrastructure on Earth's surface, in-space and on the Moon and Mars surfaces to determine LCC. This paper describes the development of specific innovative engineering and management approaches and processes. This includes a focus on flight hardware maturity for reliability, ground operations approaches, and business processes between contractor and government organizations. A major change in program/project cost control is being proposed by the SPST to achieve a sustainable space transportation system LCC - controlling cost as a program metric in addition to the existing practice of controlling performance and weight. Without a firm requirement and methodically structured cost control, it is unlikely that an affordable and sustainable space

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

    OpenAIRE

    Wang Peng; Jiang Lingyun

    2015-01-01

    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...

  14. A Service Access Security Control Model in Cyberspace

    Science.gov (United States)

    Qianmu, Li; Jie, Yin; Jun, Hou; Jian, Xu; Hong, Zhang; Yong, Qi

    A service access control model in cyberspace is proposed, which provides a generalized and effective mechanism of security management with some items constraint specifications. These constraint specifications are organized to form a construction, and an enact process is proposed to make it scalable and flexible to meet the need of diversified service application systems in cyberspace. The model of this paper erases the downward information flow by extended rules of read/write, which is the breakthrough of the limitations when applying the standard role-based access control in cyberspace.

  15. 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.

  16. Access to Health Care and Control of ABCs of Diabetes

    OpenAIRE

    Zhang, Xuanping; Bullard, Kai McKeever; Gregg, Edward W.; Beckles, Gloria L.; Williams, Desmond E.; Barker, Lawrence E; Albright, Ann L.; Imperatore, Giuseppina

    2012-01-01

    OBJECTIVE To examine the relationship between access to health care and diabetes control. RESEARCH DESIGN AND METHODS Using data from the National Health and Nutrition Examination Survey, 1999–2008, we identified 1,221 U.S. adults (age 18–64 years) with self-reported diabetes. Access was measured by current health insurance coverage, number of times health care was received over the past year, and routine place to go for health care. Diabetes control measures included the proportion of people...

  17. Comparable Measures of Accessibility to Public Transport Using the General Transit Feed Specification

    Directory of Open Access Journals (Sweden)

    Jinjoo Bok

    2016-03-01

    Full Text Available Public transport plays a critical role in the sustainability of urban settings. The mass mobility and quality of urban lives can be improved by establishing public transport networks that are accessible to pedestrians within a reasonable walking distance. Accessibility to public transport is characterized by the ease with which inhabitants can reach means of transportation such as buses or metros. By measuring the degree of accessibility to public transport networks using a common data format, a comparative study can be conducted between different cities or metropolitan areas with different public transit systems. The General Transit Feed Specification (GTFS by Google Developers allows this by offering a common format based on text files and sharing the data set voluntarily produced and contributed by the public transit agencies of many participating cities around the world. This paper suggests a method to assess and compare public transit accessibility in different urban areas using the GTFS feed and demographic data. To demonstrate the value of the new method, six examples of metropolitan areas and their public transit accessibility are presented and compared.

  18. 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.

  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. Electronic Wallet and Access Control Solution Based on RFID MiFare Cards

    Directory of Open Access Journals (Sweden)

    Stefan Victor Lefter

    2013-03-01

    Full Text Available With the advent of Radio Frequency Identification technologies or RFID for short, different types of products and security-relevant applications have been developed for use in fields and businesses like: inventory management, product tracking, access control, passports or transport fare collection. Even though RFID has been around for quite some time, there are some types of businesses like theme parks, water parks or music festivals that haven’t yet tested the benefits that this technology brings. This paper focuses on presenting advantages and disadvantages of using an unified access control and electronic wallet system based on RFID cards like MiFare tags as an alternative to existing ticket/currency access and payment systems employed by the majority of the businesses mentioned above.

  2. 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.

  3. 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…

  4. Audit-Based Access Control for Electronic Health Records

    NARCIS (Netherlands)

    Dekker, M.A.C.; Etalle, S.; Gadducci, F.

    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 acce

  5. Audit-Based Access Control for Electronic Health Records

    NARCIS (Netherlands)

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

    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 acc

  6. 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...

  7. Research on a dynamic workflow access control model

    Science.gov (United States)

    Liu, Yiliang; Deng, Jinxia

    2007-12-01

    In recent years, the access control technology has been researched widely in workflow system, two typical technologies of that are RBAC (Role-Based Access Control) and TBAC (Task-Based Access Control) model, which has been successfully used in the role authorizing and assigning in a certain extent. However, during the process of complicating a system's structure, these two types of technology can not be used in minimizing privileges and separating duties, and they are inapplicable when users have a request of frequently changing on the workflow's process. In order to avoid having these weakness during the applying, a variable flow dynamic role_task_view (briefly as DRTVBAC) of fine-grained access control model is constructed on the basis existed model. During the process of this model applying, an algorithm is constructed to solve users' requirements of application and security needs on fine-grained principle of privileges minimum and principle of dynamic separation of duties. The DRTVBAC model is implemented in the actual system, the figure shows that the task associated with the dynamic management of role and the role assignment is more flexible on authority and recovery, it can be met the principle of least privilege on the role implement of a specific task permission activated; separated the authority from the process of the duties completing in the workflow; prevented sensitive information discovering from concise and dynamic view interface; satisfied with the requirement of the variable task-flow frequently.

  8. 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

  9. Access control issues and solutions for large sites

    International Nuclear Information System (INIS)

    The Lawrence Livermore National Laboratory (LLNL) operates an automated access control system consisting of more than 100 portals. We have gained considerable practical experience in the issues involved in operating this large system, and have identified the central issues to include system reliability, the large user population, the need for central control, constant change, high visibility and the budget. This paper outlines these issues and draws from our experience to discuss some fruitful ways of addressing them

  10. Adaptive Medium Access Control Protocol for Wireless Body Area Networks

    OpenAIRE

    Javaid, N.; Ahmad, A.; A. Rahim; Z.A. Khan; M. Ishfaq; Qasim, U.

    2014-01-01

    Wireless Body Area Networks (WBANs) are widely used for applications such as modern health-care systems, where wireless sensors (nodes) monitor the parameter(s) of interest. Nodes are provided with limited battery power and battery power is dependent on radio activity. MAC protocols play a key role in controlling the radio activity. Therefore, we present Adaptive Medium Access Control (A-MAC) protocol for WBANs supported by linear programming models for the minimization of energy consumption ...

  11. 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...

  12. Access control and interlock system at the Advanced Photon Source

    Energy Technology Data Exchange (ETDEWEB)

    Forrestal, J.; Hogrefe, R.; Knott, M.; McDowell, W.; Reigle, D.; Solita, L.; Koldenhoven, R.; Haid, D. [Argonne National Lab., IL (United States). Advanced Photon Source

    1997-08-01

    The Advanced Photon Source (APS) consists of a linac, position accumulator ring (PAR), booster synchrotron, storage ring, and up to 70 experimental beamlines. The Access Control and Interlock System (ACIS) utilizes redundant programmable logic controllers (PLCs) and a third hard-wired chain to protect personnel from prompt radiation generated by the linac, PAR, synchrotron, and storage ring. This paper describes the ACIS`s design philosophy, configuration, hardware, functionality, validation requirements, and operational experience.

  13. The Association between Access to Public Transportation and Self-reported Active Commuting

    DEFF Research Database (Denmark)

    Djurhuus, Sune; Hansen, Henning Sten; Aadahl, Mette;

    2014-01-01

    Active commuting provides routine-based regular physical activity which can reduce the risk of chronic diseases. Using public transportation involves some walking or cycling to a transit stop, transfers and a walk to the end location and users of public transportation have been found to accumulate...... and self-reported active commuting. Self-reported time spent either walking or cycling commuting each day and the distance to workplace were obtained for adults aged 16 to 65 in the Danish National Health Survey 2010 (n = 28,928). Access to public transportation measures were computed by combining GIS......-based road network distances from home address to public transit stops an integrating their service level. Multilevel logistic regression was used to examine the association between access to public transportation measures and active commuting. Distance to bus stop, density of bus stops, and number...

  14. A User Profile Based Access Control Model and Architecture

    Directory of Open Access Journals (Sweden)

    Meriem Zerkouk

    2013-02-01

    Full Text Available Personalization and adaptation to the user profile capability are the hottest issues to ensure ambientassisted living and context awareness in nowadays environments. With the growing healthcare andwellbeing context aware applications, modeling security policies becomes an important issue in thedesign of future access control models. This requires rich semantics using ontology modeling for themanagement of services provided to dependant people. However, current access control models remainunsuitable due to lack of personalization, adaptability and smartness to the handicap situation.In this paper, we propose a novel adaptable access control model and its related architecture in whichthe security policy is based on the handicap situation analyzed from the monitoring of user’s behavior inorder to grant a service using any assistive device within intelligent environment. The design of ourmodel is an ontology-learning and evolving security policy for predicting the future actions of dependentpeople. This is reached by reasoning about historical data, contextual data and user behavior accordingto the access rules that are used in the inference engine to provide the right service according to theuser’s needs.

  15. Controllable spin transport in ferromagnetic graphene junctions

    OpenAIRE

    Yokoyama, Takehito

    2008-01-01

    We study spin transport in normal/ferromagnetic/normal graphene junctions where a gate electrode is attached to the ferromagnetic graphene. We find that due to the exchange field of the ferromagnetic graphene, spin current through the junctions has an oscillatory behavior with respect to the chemical potential in the ferromagnetic graphene, which can be tuned by the gate voltage. Especially, we obtain a controllable spin current reversal by the gate voltage. Our prediction of high controllabi...

  16. 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.

  17. 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......Future Internet research is needed to bring the Internet and the Things closer to each other to form the Internet of Things. As objects in our daily life gradually become smarter, there is an increasing benefit of networking these objects. In this article, a method to couple objects, the Things...... 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....

  18. 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

  19. 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.

  20. Type-Based Access Control in Data-Centric Systems

    Science.gov (United States)

    Caires, Luís; Pérez, Jorge A.; Seco, João Costa; Vieira, Hugo Torres; Ferrão, Lúcio

    Data-centric multi-user systems, such as web applications, require flexible yet fine-grained data security mechanisms. Such mechanisms are usually enforced by a specially crafted security layer, which adds extra complexity and often leads to error prone coding, easily causing severe security breaches. In this paper, we introduce a programming language approach for enforcing access control policies to data in data-centric programs by static typing. Our development is based on the general concept of refinement type, but extended so as to address realistic and challenging scenarios of permission-based data security, in which policies dynamically depend on the database state, and flexible combinations of column- and row-level protection of data are necessary. We state and prove soundness and safety of our type system, stating that well-typed programs never break the declared data access control policies.

  1. Tag Content Access Control with Identity-based Key Exchange

    Science.gov (United States)

    Yan, Liang; Rong, Chunming

    2010-09-01

    Radio Frequency Identification (RFID) technology that used to identify objects and users has been applied to many applications such retail and supply chain recently. How to prevent tag content from unauthorized readout is a core problem of RFID privacy issues. Hash-lock access control protocol can make tag to release its content only to reader who knows the secret key shared between them. However, in order to get this shared secret key required by this protocol, reader needs to communicate with a back end database. In this paper, we propose to use identity-based secret key exchange approach to generate the secret key required for hash-lock access control protocol. With this approach, not only back end database connection is not needed anymore, but also tag cloning problem can be eliminated at the same time.

  2. Individual public transportation accessibility is positively associated with self-reported active commuting

    DEFF Research Database (Denmark)

    Djurhuus, Sune; Hansen, Henning Sten; Aadahl, Mette;

    2014-01-01

    BACKGROUND: Active commuters have lower risk of chronic disease. Understanding which of the, to some extent, modifiable characteristics of public transportation that facilitate its use is thus important in a public health perspective. The aim of the study was to examine the association between...... individual public transportation accessibility and self-reported active commuting, and whether the associations varied with commute distance, age, and gender. METHODS: Twenty-eight thousand nine hundred twenty-eight commuters in The Capital Region of Denmark reported self-reported time spent either walking...... or cycling to work or study each day and the distance to work or study. Data were obtained from the Danish National Health Survey collected in February to April 2010. Individual accessibility by public transportation was calculated using a multi-modal network in a GIS. Multilevel logistic regression was used...

  3. Access and control of resources: Lessons from the SANREM CRSP

    OpenAIRE

    Flora, Cornelia B.

    2001-01-01

    Metadata only record Developing sustainability in an agricultural ecosystem requires that attention be given to inequities within communities. The experiences of SANREM CRSP revealed that gender inequality was a significant factor in the access and control of resources that were critical for the projects reaching their goals. Among the resources of financial, manufactured, human, environmental, and social capital, enhancing social capital among women was a crucial component of plans for in...

  4. Achieving Fine-grained Access Control in Virtual Organisations

    OpenAIRE

    Zhang, Nien Fan; Yao, L.; Nenadic, A.; Chin, J.; Goble, C.; Rector, A.; Chadwick, David W; Otenko, Sassa; Shi, Q.

    2007-01-01

    In a virtual organization environment, where services and data are provided and shared amongorganizations from different administrative domains and protected with dissimilar security policies and measures, there is a need for a flexible authentication framework that supports the use of various authentication methods and tokens. The authentication strengths derived from the authentication methods and tokens should be incorporated into an access-control decision-making process, so that more sen...

  5. THE ADMINISTRATOR OBJECT PATTERN FOR ROLE-BASED ACCESS CONTROL

    OpenAIRE

    S. R. KODITUWAKKU

    2010-01-01

    The Object-Oriented paradigm approaches the software development by representing real world entities into classes of software objects. Object oriented design patterns facilitate small scale and large scale design reuse. This paper presents an object oriented design pattern, Administrator Object, to address the User-Role assignment problem in Role Based Access Control (RBAC). Two alternative solutions are proposed. The pattern is presented according to the Gang of Four template.

  6. THE ADMINISTRATOR OBJECT PATTERN FOR ROLE-BASED ACCESS CONTROL

    Directory of Open Access Journals (Sweden)

    S. R. KODITUWAKKU

    2010-12-01

    Full Text Available The Object-Oriented paradigm approaches the software development by representing real world entities into classes of software objects. Object oriented design patterns facilitate small scale and large scale design reuse. This paper presents an object oriented design pattern, Administrator Object, to address the User-Role assignment problem in Role Based Access Control (RBAC. Two alternative solutions are proposed. The pattern is presented according to the Gang of Four template.

  7. SAFETY AND QUALITY CONTROL OF TRANSPORT SERVICES ON RAILWAY TRANSPORT

    Directory of Open Access Journals (Sweden)

    I. P. Sadlovska

    2010-10-01

    Full Text Available The article presents the provisions to improve procedure of licensing of passenger and freight transportation, technical specifications for services related to the passenger and freight transportations.

  8. 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.

  9. 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. PMID:15066555

  10. Material control and surveillance for high frequency access vaults project

    International Nuclear Information System (INIS)

    The 'Material Control and Surveillance for High Frequency Access Vaults' project sponsored by United States Department of Energy's Office of Security Policy, Policy Integration and Technical Support Program (SO-20.3) focuses on enhancing nuclear materials control and surveillance in vaults that are frequently accessed. The focus of this effort is to improve materials control and accountability (MC and A) while decreasing the operational impact of these activities. Los Alamos and Y-12 have developed a testbed at the Los Alamos National Laboratory for evaluating and demonstrating integrated technologies for use in enhancing materials control and accountability in active nuclear material storage vaults. An update will be provided on the new systems demonstrated in the test-bed including a 'confirmatory cart' for expediting the performance of inventory and radio-frequency actuated video that demonstrates the concept of automated data entry for materials moving between MBA's. The United States Department of Energy's Office of Security Policy, Policy Integration and Technical Support Program (SO-20.3) has sponsored a project where nuclear material inventory, control and surveillance systems are evaluated, developed, and demonstrated in an effort to provide technologies that reduce risk, increase material assurance, and provide cost-efficient alternatives to manpower-intensive physical inventory and surveillance approaches for working (high-frequency-access) vaults. This Fiscal Year has been largely focused on evaluating and developing components of two sub-systems that could be used either separately in nuclear material vaults or as part of a larger integrated system for nuclear materials accountability, control and surveillance.

  11. State control, access to capital and firm performance

    Institute of Scientific and Technical Information of China (English)

    Oliver Zhen Li; Xijia Su; Zhifeng Yang

    2012-01-01

    We study the effect of state control on capital allocation and investment in China, where the government screens prospective stock issuers. We find that state firms are more likely to obtain government approval to conduct seasoned equity offerings than non-state firms. Further, non-state firms exhibit greater sensitivities of subsequent investment and stock performance to regulatory decisions on stock issuances than state firms. Our work suggests that state control of capital access distorts resource allocation and impedes the growth of non-state firms. We also provide robust evidence that financial constraints cause underinvestment.

  12. RFID Based Security Access Control System with GSM Technology

    Directory of Open Access Journals (Sweden)

    Peter Adole

    2016-08-01

    Full Text Available The security challenges being encountered in many places today require electronic means of controlling access to secured premises in addition to the available security personnel. Various technologies were used in different forms to solve these challenges. The Radio Frequency Identification (RFID Based Access Control Security system with GSM technology presented in this work helps to prevent unauthorized access to controlled environments (secured premises. This is achieved mainly through the use of a Radio Frequency Identification System with operating frequency of 125 KHz, Microcontroller programmed to send control signals, DC motor, relay, buzzer, Liquid Crystal Display (LCD and GSM/GPRS Modem.Once the RFID tag which contains the user’s unique information is scan by the RFID reader and confirmed match with the information stored in the microcontroller, the microcontroller is instructed to turn ON the DC motor through L293D driver, display “USER NUMBER and CARD NUMBER” on the LCD and activates the GSM/GPRS modem to send SMS alert “AUTHORIZED, valid RFID card shown, User is allowed to enter, user number” to security personnel. Else, the DC Motor remained OFF, LCD displays “READ RFID CARD NOT VALID”, buzzer turns ON for about 5seconds and GSM/GPRS modem activated to send “ UNAUTHORIZED, invalid RFID card is used to access the security system” to the security personnel. The electronic circuit was implemented, the codes for microcontroller were written in assembly language, 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. Hardware simulation was carried out using the Proteus Virtual System Modelling (VSM version 8.0.An importation implication of this paper is that the system is cheaper to maintain and more efficient in comparison with a manually operated type or key lock

  13. 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.

  14. 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.

  15. Flight Controller Design of Transport Airdrop

    Institute of Scientific and Technical Information of China (English)

    CHEN Jie; SHIZhongke

    2011-01-01

    During airdrop of heavy load,the flight paramctcrs vary continuously as the load moves in the hold,and change suddenly when the load drops out.This process deteriorates the flight quality and control characteristic as the load becomes heavier.Based on the simplified airdrop flight equations,the backstepping and switch control methods are developed to tackle the flight state holding and disturbance/uncertainty(such as large scale flight condition,pilot manipulation error,system measure delay,etc.)attenuation problem in this paper.Moreover,these methods can be used as a reference for pilot manipulating during airdrop.With the backstepping theory,an adaptive controller is synthesized for the purpose of stabilizing the transport when the load moves in the hold,and then a coordinated switch control method is used to control the aircraft when the condition jumps from the existence of load at the rear of fuselage to no load in the fuselage.Simulation results show that the proposed controllers not only provide effective state holding during airdrop,but also achieve robust performance within wide flight conditions.

  16. 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.

  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. Smartphone-based system to improve transportation access for the cognitively impaired.

    Science.gov (United States)

    Anderson, Shane M; Riehle, Timothy H; Lichter, Patrick A; Brown, Allen W; Panescu, Dorin

    2015-08-01

    This project developed and evaluated a smartphone-based system to improve mobility and transportation access for the cognitively impaired. The proposed system is intended to allow the cognitively impaired to use public transportation systems, community transportation and dedicated transportation services for the disabled with greater ease and safety. Individuals with cognitive disabilities are often unable to operate an automobile, or may require a prolonged recovery period before resuming driving. Public transportation systems represent a significant means to allow these individuals to maintain independence. Yet public transportation systems can pose significant challenges to individuals with cognitive impairment. The goal of this project is to develop a system to reduce these barriers via a technological solution consisting of components developed both for the cognitively impaired user and their caregiver or family member. The first component consists of a cognitive prosthetic device featuring traditional memory cueing and reminders as well as custom location-based transportation specific functions. This cognitive mobility assistant will leverage the computing power and GPS location determination capabilities of inexpensive, powerful smart phones. The second component consists of a management application which offers caregivers the ability to configure and program the reminder and transit functions remotely via the Internet. Following completion of the prototype system a pilot human test was performed with cognitively disabled individuals and family members or caregivers to assess the usability and acceptability of both system components. PMID:26738091

  19. 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.

  20. 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.

  1. 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...

  2. Accessible Transportation, Geographic Elevation, and Masticatory Ability Among Elderly Residents of a Rural Area

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Hamano

    2015-06-01

    Full Text Available Given that public transportation networks are often worse in rural areas than in urban areas, rural residents who do not drive can find it difficult to access health-promoting goods, services, and resources related to masticatory ability. Moreover, geographical location, assessed by elevation, could modify this association. The aim of this study was to test whether the association between access to transportation and masticatory ability varied by elevation. Data were collected from a cross-sectional study conducted in Mizuho and Iwami counties, Japan. Objective masticatory ability was evaluated using a test gummy jelly and elevation was estimated by the geographic information systems according to the participant’s address. After excluding subjects with missing data, 672 subjects (Mizuho = 401 and Iwami = 271 were analyzed. After adjustment for potential confounders, being a driver was not significantly associated with masticatory ability among elderly people living at low elevation (≤313 m in Mizuho county. However, after the same adjustment, being a driver remained significantly associated with increased masticatory ability among elderly at high elevations. Similar findings were observed in Iwami county. Accessible transportation was significantly associated with increased mastication ability in elderly people living at high elevations, but not in those living at low elevations.

  3. Accessibility modeling and evaluation: the TIGRIS XL land-use and transport interaction model for the Netherlands

    NARCIS (Netherlands)

    Zondag, B.; Bok, de M.; Geurs, K.T.; Molenwijk, E.

    2015-01-01

    In current practice, transportation planning often ignores the effects of major transportation improvements on land use and the distribution of land use activities, which might affect the accessibility impacts and economic efficiency of the transportation investment strategies. In this paper, we des

  4. 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.

  5. Extending a Role Graph for Role-Based Access Control

    Science.gov (United States)

    Asakura, Yoshiharu; Nakamoto, Yukikazu

    Role-based access control (RBAC) is widely used as an access control mechanism in various computer systems. Since an organization's lines of authority influence the authorized privileges of jobs, roles also form a hierarchical structure. A role graph is a model that represents role hierarchies and is suitable for the runtime phase of RBAC deployment. Since a role graph cannot take various forms for given roles and cannot handle abstraction of roles well, however, it is not suitable for the design phase of RBAC deployment. Hence, an extended role graph, which can take a more flexible form than that of a role graph, is proposed. The extended role graph improves diversity and clarifies abstraction of roles, making it suitable for the design phase. An equivalent transformation algorithm (ETA), for transforming an extended role graph into an equivalent role graph, is also proposed. Using the ETA, system administrators can deploy efficiently RBAC by using an extended role graph in the design phase and a standard role graph in the runtime phase.

  6. BWR startup and shutdown activity transport control

    International Nuclear Information System (INIS)

    This paper summarizes BWR industry experience on good practices for controlling the transport of corrosion product activity during shutdowns, particularly refueling outages, and for startup chemistry control to minimize IGSCC (intergranular stress corrosion cracking). For shutdown, overall goals are to minimize adverse impacts of crud bursts and the time required to remove activated corrosion products from the reactor coolant during the shutdown process prior to refueling, and to assist plants in predicting and controlling radiation exposure during outages. For startup, the overall goals are to highlight conditions during early heatup and startup when sources of reactor coolant oxidants are high, when there is a greater likelihood for chemical excursions associated with refueling outage work activities, and when hydrogen injection is not available to mitigate IGSCC due to system design limitations. BWR water chemistry has changed significantly in recent years with the adoption of hydrogen water chemistry, zinc addition and noble metal chemical applications. These processes have, in some instances, resulted in significant activity increases during shutdown evolutions, which together with reduced time for cleanup because of shorter outages, has consequently increased outage radiation exposure. A review several recent outages shows that adverse effects from these conditions can be minimized, leading to the set of good practice recommendations for shutdown chemistry control. Most plants lose the majority of their hydrogen availability hours during early startup because feedwater hydrogen injection systems were not originally designed to inject hydrogen below 20% power. Hydrogen availability has improved through modifications to inject hydrogen at lower power levels, some near 5%. However, data indicate that IGSCC is accelerated during early startup, when dissolved oxygen and hydrogen peroxide levels are high and reactor coolant temperatures are in the 300 to 400 oF (

  7. 76 FR 60398 - Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control...

    Science.gov (United States)

    2011-09-29

    ... Prohibition on Circumvention of Copyright Protection Systems for Access Control Technologies, 68 FR 62011... Circumvention of Copyright Protection Systems for Access Control Technologies, 71 FR 68472, 68480, published in... Protection Systems for Access Control Technologies, 65 FR 64556, 64564, published in the Federal...

  8. 75 FR 4007 - Risk Management Controls for Brokers or Dealers With Market Access

    Science.gov (United States)

    2010-01-26

    ... COMMISSION 17 CFR Part 240 RIN 3235-AK53 Risk Management Controls for Brokers or Dealers With Market Access... market access to customers or other persons, to implement risk management controls and supervisory... pre-trade risk management controls (i.e., ``unfiltered'' or ``naked'' access),\\10\\ and thus could...

  9. 77 FR 2343 - Eleventh Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-01-17

    ...). 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 a.m.-4..., Airport Security Access Control Systems. The agenda will include the following: February 9, 2012...

  10. 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.

  11. Trust-based Access Control in Virtual Learning Community

    Science.gov (United States)

    Wang, Shujuan; Liu, Qingtang

    The virtual learning community is an important application pattern of E-Learning. It emphasizes the cooperation of the members in the community, the members would like to share their learning resources, to exchange their experience and complete the study task together. This instructional mode has already been proved as an effective way to improve the quality and efficiency of instruction. At the present time, the virtual learning communities are mostly designed using static access control policy by which the access permission rights are authorized by the super administrator, the super administrator assigns different rights to different roles, but the virtual and social characteristics of virtual learning community make information sharing and collaboration a complex problem, the community realizes its instructional goal only if the members in it believe that others will offer the knowledge they owned and believe the knowledge others offered is well-meaning and worthy. This paper tries to constitute an effective trust mechanism, which could promise favorable interaction and lasting knowledge sharing.

  12. A Semantic Context-Based Model for MobileWeb Services Access Control

    OpenAIRE

    Haibo Shen; Yu Cheng

    2011-01-01

    As mobile web services becomes more pervasive, applications based on mobile web services will need flexible access control mechanisms. Unlike traditional approaches based on the identity or role for access control, access decisions for these applications will depend on the combination of the required attributes of users and the contextual information. This paper proposes a semantic context-based access control model (called SCBAC) to be applied in mobile web services environment by combining ...

  13. 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...

  14. New perspective on the accessibility of railway transport for the vulnerable traveller

    International Nuclear Information System (INIS)

    Vulnerable travellers experience various problems in the transport environment. These may reduce public travel confidence and consequently lead to decreased mobility. A goal of our research is to find out how to improve the accessibility to railway travelling, especially, for persons with functional limitations. By reducing barriers, the ability of travelling would be improved, and consequently allow for more flexible travel behaviors. In order to develop a model and a method of measurement for accessibility, we (a) constructed a reference group of representative 'typical older persons' (65–85 years) from questionnaire data, and (b) developed an accessibility measure for persons with functional limitations. In this measure barriers have different weights for the different persons depending on their functional ability and travel behavior. This gives the probability of facing a certain barrier when travelling to a certain destination; that is, a measure of accessibility for the individual. The more weight placed on a certain barrier, the less probable it is that the particular journey will take place. These weights will be obtained in forthcoming research on the perception of a set of various travel scenarios representing barriers

  15. 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. PMID:23629061

  16. Structural basis of the alternating-access mechanism in a bile acid transporter

    Science.gov (United States)

    Zhou, Xiaoming; Levin, Elena J.; Pan, Yaping; McCoy, Jason G.; Sharma, Ruchika; Kloss, Brian; Bruni, Renato; Quick, Matthias; Zhou, Ming

    2014-01-01

    Bile acids are synthesized from cholesterol in hepatocytes and secreted through the biliary tract into the small intestine, where they aid in absorption of lipids and fat-soluble vitamins. Through a process known as enterohepatic recirculation, more than 90% of secreted bile acids are then retrieved from the intestine and returned to the liver for resecretion. In humans, there are two Na+-dependent bile acid transporters involved in enterohepatic recirculation, the Na+-taurocholate co-transporting polypeptide (NTCP; also known as SLC10A1) expressed in hepatocytes, and the apical sodium-dependent bile acid transporter (ASBT; also known as SLC10A2) expressed on enterocytes in the terminal ileum. In recent years, ASBT has attracted much interest as a potential drug target for treatment of hypercholesterolaemia, because inhibition of ASBT reduces reabsorption of bile acids, thus increasing bile acid synthesis and consequently cholesterol consumption. However, a lack of three-dimensional structures of bile acid transporters hampers our ability to understand the molecular mechanisms of substrate selectivity and transport, and to interpret the wealth of existing functional data. The crystal structure of an ASBT homologue from Neisseria meningitidis (ASBTNM) in detergent was reported recently, showing the protein in an inward-open conformation bound to two Na+ and a taurocholic acid. However, the structural changes that bring bile acid and Na+ across the membrane are difficult to infer from a single structure. To understand the structural changes associated with the coupled transport of Na+ and bile acids, here we solved two structures of an ASBT homologue from Yersinia frederiksenii (ASBTYf) in a lipid environment, which reveal that a large rigid-body rotation of a substrate-binding domain gives the conserved `crossover' region, where two discontinuous helices cross each other, alternating accessibility from either side of the cell membrane. This result has implications

  17. Enhancing Security and Privacy in Video Surveillance through Role-Oriented Access Control Mechanism

    DEFF Research Database (Denmark)

    Mahmood Rajpoot, Qasim

    that is suitable for video surveillance systems as well as other domains sharing similar requirements. As the currently dominant access control models – the role-based access control (RBAC) and the attribute-based access control (ABAC) – suffer from limitations while offering features complementary to each other...... while addressing the role- and permission-explosion issues faced in RBAC. Based on our access control model, we then present an access control mechanism for video surveillance systems. Contrary to the existing approaches, the proposed access control mechanism is role-oriented and retains advantages...... associated with role-based access control, yet it allows specification of policies using the metadata associated with the objects as well as the attributes of users and environment. In addition to role hierarchies, the content-based permissions in our model allow derivation of several permissions from...

  18. Intelligent Urban Public Transportation for Accessibility Dedicated to People with Disabilities

    Directory of Open Access Journals (Sweden)

    Jian Li

    2012-08-01

    Full Text Available The traditional urban public transport system generally cannot provide an effective access service for people with disabilities, especially for disabled, wheelchair and blind (DWB passengers. In this paper, based on advanced information & communication technologies (ICT and green technologies (GT concepts, a dedicated public urban transportation service access system named Mobi+ has been introduced, which facilitates the mobility of DWB passengers. The Mobi+ project consists of three subsystems: a wireless communication subsystem, which provides the data exchange and network connection services between buses and stations in the complex urban environments; the bus subsystem, which provides the DWB class detection & bus arrival notification services; and the station subsystem, which implements the urban environmental surveillance & bus auxiliary access services. The Mobi+ card that supports multi-microcontroller multi-transceiver adopts the fault-tolerant component-based hardware architecture, in which the dedicated embedded system software, i.e., operating system micro-kernel and wireless protocol, has been integrated. The dedicated Mobi+ embedded system provides the fault-tolerant resource awareness communication and scheduling mechanism to ensure the reliability in data exchange and service provision. At present, the Mobi+ system has been implemented on the buses and stations of line ‘2’ in the city of Clermont-Ferrand (France. The experiential results show that, on one hand the Mobi+ prototype system reaches the design expectations and provides an effective urban bus access service for people with disabilities; on the other hand the Mobi+ system is easily to deploy in the buses and at bus stations thanks to its low energy consumption and small form factor.

  19. Towards convergence of wireless and wireline signal transport in broadband access networks

    DEFF Research Database (Denmark)

    Yu, Xianbin; Prince, Kamau; Tafur Monroy, Idelfonso

    2010-01-01

    Hybrid optical wireless access networks are to play an important role in the realization of the vision of delivery of broadband services to the end-user any time, anywhere and at affordable costs. We present results of experiments conducted over a field deployed optical fibre links we successfull...... demonstrated converged wireless and wireline signal transport over a common fibre infrastructure. The type of signal used in this field deployed experiments cover WiMax, Impulse-radio ultra-wideband (UWB) and coherent transmission of baseband QPSK and radio-over-fibre signals....

  20. Accessibility appraisal of land-use/transport policy strategies: More than just adding up travel-time savings

    NARCIS (Netherlands)

    Geurs, Karst; Zondag, Barry; Jong, de Gerard; Bok, de Michiel

    2010-01-01

    We examine the accessibility benefits associated with some land-use policy strategies for the Netherlands that anticipate on expected climate change. A disaggregate logsum accessibility measure using the Dutch national land-use/transport interaction model TIGRIS XL is used to compute changes in cons

  1. 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...... 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...... emergency response scenario which highlights the novel challenges that arise when enforcing access control in an environment with moving subjects and objects. To address a realistic application scenario, we consider movement on road networks, and we identify complex access control decisions relevant...

  2. Cross-layer rate control, medium access control and routing design in cooperative VANET

    OpenAIRE

    Zhou, Liang; Zheng, Baoyu; Geller, Benoit; Wei, Anne; Xu, Shan; Li, Yajun

    2008-01-01

    In this paper, we address the rate control, the Medium Access Control (MAC) and the routing problem for cooperative Vehicular Ad-Hoc Network (VANET) in the framework of cross-layer design. At first, we introduce the cooperative communication conception to VANET, and propose an opportunistic cooperation strategy to improve the system performance. And then, we develop a cross-layer solution which consists of the link capacity detection with adjusting persistence probability at the MAC Layer, th...

  3. 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.

  4. The use of modern information technology in research on transport accessibility

    Directory of Open Access Journals (Sweden)

    Bartosz BARTOSIEWICZ

    2015-09-01

    Full Text Available Transport accessibility can be analyzed using a number of different methods. The problem with each of them is the difficulty of obtaining data to measure this phenomenon The focus of this article and its main goal are to present methods and tools for gathering data on road traffic; thanks to modern information technology, it is possible to collect real data without the need for large-scale and highly capital-intensive measurements. The application of modern information technology (IT presented in the article, such as computer programs and applications like Google Maps Traffic Overlay and TomTom Live Traffic, enable research to be conducted on a scale that has thus far been unattainable, and allows information to be collected on such criteria as traffic volume, flow, average traffic speed, and actual journey time. Such innovative means of gathering data on automobile traffic open up new perspectives for assessing transport accessibility in terms of automobile traffic by providing high-quality data that meet the requirements for use in primary research.

  5. The Effect of Transport Accessibility on the Social Inclusion of Wheelchair Users: A Mixed Method Analysis

    Directory of Open Access Journals (Sweden)

    Raquel Velho

    2016-06-01

    Full Text Available In recent years the accessibility of London buses has improved with the introduction of ramps and wheelchair priority areas. These advances are meant to remove physical barriers to entering the bus, but new conflicts have arisen particularly over the physical space aboard. We aimed to research the barriers faced by wheelchair users in public transport using a mixed methods approach to establish the breadth of issues faced by wheelchair users. To this end we quantified the push-force used alight a bus and a study to understand the coping mechanisms used by people to propel up a ramp. This quantitative approach found push forces which resulted in a load of 2 to 3 times body weight being transferred through people’s shoulders, forces which can be directly linked to shoulder injury. This could disable the user further, preventing them from being able to push their wheelchair. Alongside the quantitative study, we conducted qualitative research comprising of a number of in-depth interviews with wheelchair users about the barriers they face in public transport. Our main claim, highlighted through this interdisciplinary collaboration, is that proposed ‘solutions’ to accessibility, such as ramps, often generate problems of their own. These barriers can affect the life of wheelchair users, impacting on their confidence and causing social isolation. These can be long-term in nature or immediate.

  6. 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.

  7. Access Control Mechanisms for Semantic Web services-A Discussion on Requirements & Future Directions

    CERN Document Server

    Gondara, Mandeep Kaur

    2011-01-01

    Semantic Web is an open, distributed, and dynamic environment where access to resources cannot be controlled in a safe manner unless the access decision takes into account during discovery of web services. Security becomes the crucial factor for the adoption of the semantic based web services. An access control means that the users must fulfill certain conditions in order to gain access over web services. Access control is important in both perspectives i.e. legal and security point of view. This paper discusses important requirements for effective access control in semantic web services which have been extracted from the literature surveyed. I have also discussed open research issues in this context, focusing on access control policies and models in this paper.

  8. Enhanced Role Based Access Control Mechanism for Electronic Examination System

    Directory of Open Access Journals (Sweden)

    Adebukola Onashoga

    2014-02-01

    Full Text Available Over the years, e-learning and e-examination has become standard in many institutions of higher learning. It has been observed that examination questions and results can be easily intercepted by invalid users, thus the security of resources shared among valid users is not guaranteed. In order to solve these problems as it relates to access control, a Role based Examination System (RBES was designed, developed and evaluated. RBES attempted to solve the security issue by the combination of two authentication techniques: text-based authentication and graphical password authentication. The Text-based authentication utilizes two text-based parameters namely the username and password. The graphical password authentication makes use of a finite set of controls (RBES chooses radio buttons which are identified by numbers. These numbers constitute the password used for graphical authentication. To improve on resource sharing among users in the examination system, RBES proposes role management (role creation, role update, role removal and user management (user creation, user update and user removal. The developed system made use of asp.net, C#, IIS server, WAMP server, Mysql and other tools for its development. RBES was tested by some legitimate and illegitimate users and the performance of the system was found to be satisfactory, hence RBES shows an efficient and reliable scheme that can be deployed in any examination or e-learning system. Finally the potential threats to the system were modeled and the use of weak passwords was found to be the most likely threat the system could be vulnerable to.

  9. 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.

  10. 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.

  11. REDUCTION IN PROBABILITY OF TRAFFIC CONGESTION ON HIGH-CLASS ROAD USING RAMP ACCESS CONTROL

    Directory of Open Access Journals (Sweden)

    R. Yu. Lagerev

    2016-01-01

    Full Text Available Мerging traffic junctions on high-class roads are considered as bottlenecks in the network and quality of their operation determines a probability for formation of traffic congestions. Investigations on congestion situations in the merging zones of ramp and freeway traffic flows have demonstrated that queuing ramp traffic flow leads to formation of so called “turbulence” effect due to re-arrangement of transport facilities and reduction in their speed on main road direction. Having high queuing traffic flow on main road the “turbulence” component can result in formation of an impact blow in the main traffic flow. It has been proved that an impact of the ramp traffic flow on congestion probability is higher in comparison with main road traffic flow. The paper makes it possible to establish that some transport facilities moving along a high-way simul taneously occupy two lanes in the merging traffic zones and they reduce capacity of the used road section. It is necessary to take into account this specific feature and it is necessary to pay attention to it in the zones of “turbulence” effect formation. The paper presents main approaches, methodology, principles and stages required for access control of high-class roads which are directed on higher quality of their operation including improvement of road traffic safety. The paper proposes a methodоlogy that allows to evaluate and optimize ramp control in the context of a transport queue length minimization at adjoining ramps for the purposes of probability reduction in transport congestion.

  12. 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...

  13. 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...

  14. Broadband passive optical network media access control protocols

    Science.gov (United States)

    Quayle, Alan

    1996-11-01

    Most telecommunication operators are currently deciding on how to respond to customers' needs stimulated by the synergy between compression coding of multimedia and the emergence of broadband digital networks. This paper describes a range of broadband access architectures under consideration in the full services access network initiative. All architectures have a common requirement for a broadband ATM PON. A common broadband PON applicable to many operators increases the world-wide market for the product. With greater production volumes manufacturers' costs reduce because of the experience curve effect making broadband access systems economic.

  15. Control of machine functions or transport systems

    Energy Technology Data Exchange (ETDEWEB)

    Woodley, M.D.; Lee, M.J.; Jaeger, J.; King, A.S.

    1983-01-01

    A computer code, COMFORT, has been developed at SLAC for on-line calculation of the strengths of magnetic elements in an electron storage ring or transport beam line, subject to first order fitting constraints on the ring or beam line parameters. This code can also be used off-line as an interactive lattice or beam line design tool.

  16. 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.

  17. 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...

  18. 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.

  19. 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. PMID:26559071

  20. Designing a Secure E-commerce with Credential Purpose-based Access Control

    OpenAIRE

    Norjihan Abdul Ghani; Harihodin Selamat; Zailani Mohamed Sidek

    2014-01-01

    The rapid growth of e-commerce has created a great opportunities for both businesses and end users. The essential e-commerce process is required for the successful operation and management of e-commerce activities. One of the processes is access control and security. E-commerce must establish a secure access between the parties in an e-commerce transaction by authenticating users, authorizing access, and enforcing security features. The e-commerce application must authorize access to only tho...

  1. 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.

  2. Sociospatial distribution of access to facilities for moderate and vigorous intensity physical activity in Scotland by different modes of transport

    Directory of Open Access Journals (Sweden)

    Lamb Karen E

    2012-07-01

    Full Text Available Abstract Background People living in neighbourhoods of lower socioeconomic status have been shown to have higher rates of obesity and a lower likelihood of meeting physical activity recommendations than their more affluent counterparts. This study examines the sociospatial distribution of access to facilities for moderate or vigorous intensity physical activity in Scotland and whether such access differs by the mode of transport available and by Urban Rural Classification. Methods A database of all fixed physical activity facilities was obtained from the national agency for sport in Scotland. Facilities were categorised into light, moderate and vigorous intensity activity groupings before being mapped. Transport networks were created to assess the number of each type of facility accessible from the population weighted centroid of each small area in Scotland on foot, by bicycle, by car and by bus. Multilevel modelling was used to investigate the distribution of the number of accessible facilities by small area deprivation within urban, small town and rural areas separately, adjusting for population size and local authority. Results Prior to adjustment for Urban Rural Classification and local authority, the median number of accessible facilities for moderate or vigorous intensity activity increased with increasing deprivation from the most affluent or second most affluent quintile to the most deprived for all modes of transport. However, after adjustment, the modelling results suggest that those in more affluent areas have significantly higher access to moderate and vigorous intensity facilities by car than those living in more deprived areas. Conclusions The sociospatial distributions of access to facilities for both moderate intensity and vigorous intensity physical activity were similar. However, the results suggest that those living in the most affluent neighbourhoods have poorer access to facilities of either type that can be reached on foot

  3. Controlling Quantum Transport with a Programmable Nanophotonic Processor

    Science.gov (United States)

    Harris, Nicholas; Steinbrecher, Gregory; Mower, Jacob; Lihini, Yoav; Prabhu, Mihika; Baehr-Jones, Tom; Hochberg, Michael; Lloyd, Seth; Englund, Dirk

    Recent experimental and theoretical work has revealed emergent, counter-intuitive quantum transport effects in a range of physical medial including solid-state and biological systems. Photonic integrated circuits are promising platforms for studying such effects. A central goal in for photonic quantum transport simulators has been the ability to rapidly control all parameters of the transport problem. Here, we present a large-scale programmable nanophotonic processor composed of 56 Mach-Zehnder interferometers that enables control over modal couplings and differential phases between modes--enabling observations of Anderson localization, environment-assisted quantum transport, ballistic transport, and a number of intermediate quantum transport regimes. Rapid programmability enables tens of thousands of realizations of disordered and noisy systems. In addition, low loss makes this nanophotonic processor a promising platform for many-boson quantum simulation experiments.

  4. Intelligent Transportation Control based on Proactive Complex Event Processing

    Directory of Open Access Journals (Sweden)

    Wang Yongheng

    2016-01-01

    Full Text Available Complex Event Processing (CEP has become the key part of Internet of Things (IoT. Proactive CEP can predict future system states and execute some actions to avoid unwanted states which brings new hope to intelligent transportation control. In this paper, we propose a proactive CEP architecture and method for intelligent transportation control. Based on basic CEP technology and predictive analytic technology, a networked distributed Markov decision processes model with predicting states is proposed as sequential decision model. A Q-learning method is proposed for this model. The experimental evaluations show that this method works well when used to control congestion in in intelligent transportation systems.

  5. Supporting a Design Driven Approach to Social Inclusion and Accessibility in Transport

    Directory of Open Access Journals (Sweden)

    Russell Marshall

    2016-06-01

    Full Text Available This paper presents research into the area of public transport and accessibility, addressing the support of practitioners in achieving socially inclusive solutions to the mobility issues of diverse populations. For decades, social policy has been underpinned by a stereotyping of populations into simplified sub groups: old, young, disabled, etc. and thus solutions often fail to properly address the richness of human variability. These shortcomings are often ‘managed’ through the ability for people to adapt, however, this is not a sustainable way in which to build a socially inclusive transport infrastructure. A software design tool called HADRIAN is presented. This tool provides a means to evaluate designs for their physical inclusiveness through the use of a virtual user group. This virtual user group is the embodiment of over 100 people that can be used to assess an existing or proposed design and to gain an understanding of what may be done to improve its accommodation. A case study exploring the use of the tool is described together with work in exploring the correlation of the individuals within the HADRIAN system with data on the UK population as a whole and how the inclusion or exclusion of individuals with specific characteristics can be used to inform a more representative view of the inclusiveness of a design.

  6. 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.

  7. On the Decidability of the Safety Problem for Access Control Policies

    OpenAIRE

    Kleiner, Eldar; Newcomb, Tom

    2006-01-01

    An access control system regulates the rights of users to gain access to resources in accordance with a specified policy. The rules in this policy may interact in a way that is not obvious via human inspection; there is, therefore, a need for automated verification techniques that can check whether a policy does indeed implement some desired security requirement. Thirty years ago, a formalisation of access control presented a model and a safety specification for which satisfaction is undecida...

  8. Random access procedures and radio access network (RAN) overload control in standard and advanced long-term evolution (LTE and LTE-A) networks

    DEFF Research Database (Denmark)

    Kiilerich Pratas, Nuno; Thomsen, Henning; Popovski, Petar

    2015-01-01

    In this chapter, we describe and discuss the current LTE random access procedure and the Radio Access Network Load Control solution within LTE/LTE-A. We provide an overview of the several considered load control solutions and give a detailed description of the standardized Extended Access Class...... Barring solution. We then provide a brief overview of the Load Control solutions provided by the Enhanced Packet Core (EPC) Network and how they intertwine with the Extended Access Barring at the Enhanced Universal Terrestrial Radio Access Network (E-UTRAN). We also provide an outlook on the current 3GPP...... efforts in regards to MTC related load control issues....

  9. 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.

  10. 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

  11. 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

  12. 77 FR 71474 - Seventeenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-11-30

    ...). 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, 2012... Federal Aviation Administration Seventeenth Meeting: RTCA Special Committee 224, Airport Security...

  13. 78 FR 43963 - Twenty-Third Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-07-22

    ...). 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, 2013... Federal Aviation Administration Twenty-Third Meeting: RTCA Special Committee 224, Airport Security...

  14. 77 FR 64838 - Sixteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-10-23

    ...). 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, 2012... Federal Aviation Administration Sixteenth Meeting: RTCA Special Committee 224, Airport Security...

  15. 78 FR 16757 - Twentieth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-03-18

    ...). 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 9... Federal Aviation Administration Twentieth Meeting: RTCA Special Committee 224, Airport Security...

  16. 78 FR 31627 - Twenty-Second Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-05-24

    ...). 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, 2013... Federal Aviation Administration Twenty-Second Meeting: RTCA Special Committee 224, Airport Security...

  17. 78 FR 7850 - Nineteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-02-04

    ...). 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, 2013... Federal Aviation Administration Nineteenth Meeting: RTCA Special Committee 224, Airport Security...

  18. 77 FR 55894 - Fifteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-09-11

    ...). 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, 2012... Federal Aviation Administration Fifteenth Meeting: RTCA Special Committee 224, Airport Security...

  19. 78 FR 22025 - Twenty First Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-04-12

    ...). 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, 2013... Federal Aviation Administration Twenty First Meeting: RTCA Special Committee 224, Airport Security...

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Optogenetic control of organelle transport and positioning

    NARCIS (Netherlands)

    van Bergeijk, Petra; Adrian, Max; Hoogenraad, Casper C; Kapitein, Lukas C

    2015-01-01

    Proper positioning of organelles by cytoskeleton-based motor proteins underlies cellular events such as signalling, polarization and growth. For many organelles, however, the precise connection between position and function has remained unclear, because strategies to control intracellular organelle

  5. 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...

  6. 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.

  7. Optimal traffic control in highway transportation networks using linear programming

    KAUST Repository

    Li, Yanning

    2014-06-01

    This article presents a framework for the optimal control of boundary flows on transportation networks. The state of the system is modeled by a first order scalar conservation law (Lighthill-Whitham-Richards PDE). Based on an equivalent formulation of the Hamilton-Jacobi PDE, the problem of controlling the state of the system on a network link in a finite horizon can be posed as a Linear Program. Assuming all intersections in the network are controllable, we show that the optimization approach can be extended to an arbitrary transportation network, preserving linear constraints. Unlike previously investigated transportation network control schemes, this framework leverages the intrinsic properties of the Halmilton-Jacobi equation, and does not require any discretization or boolean variables on the link. Hence this framework is very computational efficient and provides the globally optimal solution. The feasibility of this framework is illustrated by an on-ramp metering control example.

  8. 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.

  9. 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.

  10. 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.

  11. 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...... to complexity and dynamics of device identities. ICAC is implemented for 802.11 and results shows that ICAC has less scalability issues and better performance analysis compared with other access control schemes. The ICAC evaluation by using security protocol verification tool shows that ICAC is secure against...

  12. 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.

  13. Rebuilding women's livelihoods strategies at the city fringe: agency, spatial practices, and access to transportation from Semmencherry, Chennai

    NARCIS (Netherlands)

    A. Alberts; K. Pfeffer; I. Baud

    2015-01-01

    Existing debates suggest that resettlement leads to exclusion of the urban poor from the city, linked to interrupted livelihoods and lack of accessibility to the city. This paper analyses the ways in which public transport mobility plays a role in the livelihood strategies of women living in a reset

  14. Management Tools of Cost Controlling at the Gas Transportation Enterprise

    OpenAIRE

    Vera Vladimirovna Plenkina; Ayapbergen Taubayev; Olga Viktorovna Lenkova

    2016-01-01

    The importance of controlling in modern conditions is defined. A brief overview of the main evolutionary stages in the development of the theory and methodology of controlling is provided. The expediency of projection of the concept of controlling on the cost management system at the gas transportation enterprise is justified. The paper points at the grouping of controlling methods in general scientific methods, methods of a number of individual sciences, and specific methods, which are offer...

  15. 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.

  16. The control of purity and stoichiometry of compound semiconductors by high vapor pressure transport

    Science.gov (United States)

    Bachmann, Klaus J.; Ito, Kazufumi; Scroggs, Jeffery S.; Tran, Hien T.

    1995-01-01

    In this report we summarize the results of a three year research program on high pressure vapor transport (HPVT) of compound semiconductors. Most of our work focused onto pnictides, in particular ZnGeP2, as a model system. Access to single crystals of well controlled composition of this material is desired for advancing the understanding and control of its point defect chemistry in the contest of remote, real-time sensing of trace impurities, e.g., greenhouse gases, in the atmosphere by ZnGeP2 optical parametric oscillators (OPO's).

  17. Control of exciton transport using quantum interference

    Science.gov (United States)

    Lusk, Mark T.; Stafford, Charles A.; Zimmerman, Jeramy D.; Carr, Lincoln D.

    2015-12-01

    It is shown that quantum interference can be employed to create an exciton transistor. An applied potential gates the quasiparticle motion and also discriminates between quasiparticles of differing binding energy. When implemented within nanoscale assemblies, such control elements could mediate the flow of energy and information. Quantum interference can also be used to dissociate excitons as an alternative to using heterojunctions. A finite molecular setting is employed to exhibit the underlying discrete, two-particle, mesoscopic analog to Fano antiresonance. Selected entanglement measures are shown to distinguish regimes of behavior which cannot be resolved from population dynamics alone.

  18. Competent authority regulatory control of the transport of radioactive material

    International Nuclear Information System (INIS)

    The purpose of this guide is to assist competent authorities in regulating the transport of radioactive materials and to assist users of transport regulations in their interactions with competent authorities. The guide should assist specifically those countries which are establishing their regulatory framework and further assist countries with established procedures to harmonize their application and implementation of the IAEA Regulations. This guide specifically covers various aspects of the competent authority implementation of the IAEA Regulations for the Safe Transport of Radioactive Material. In addition, physical protection and safeguards control of the transport of nuclear materials as well as third party liability aspects are briefly discussed. This is because they have to be taken into account in overall transport regulatory activities, especially when establishing the regulatory framework

  19. Quantum transport of energy in controlled synthetic quantum magnets

    Science.gov (United States)

    Bermudez, Alejandro; Schaetz, Tobias

    2016-08-01

    We introduce a theoretical scheme that exploits laser cooling and phonon-mediated spin–spin interactions in crystals of trapped atomic ions to explore the transport of energy through a quantum magnet. We show how to implement an effective transport window to control the flow of energy through the magnet even in the absence of fermionic statistics for the carriers. This is achieved by shaping the density of states of the effective thermal reservoirs that arise from the interaction with the external bath of the modes of the electromagnetic field, and can be experimentally controlled by tuning the laser frequencies and intensities appropriately. The interplay of this transport window with the spin–spin interactions is exploited to build an analogue of the Coulomb-blockade effect in nano-scale electronic devices, and opens new possibilities to study quantum effects in energy transport.

  20. Enhancing coherent transport in a photonic network using controllable decoherence.

    Science.gov (United States)

    Biggerstaff, Devon N; Heilmann, René; Zecevik, Aidan A; Gräfe, Markus; Broome, Matthew A; Fedrizzi, Alessandro; Nolte, Stefan; Szameit, Alexander; White, Andrew G; Kassal, Ivan

    2016-01-01

    Transport phenomena on a quantum scale appear in a variety of systems, ranging from photosynthetic complexes to engineered quantum devices. It has been predicted that the efficiency of coherent transport can be enhanced through dynamic interaction between the system and a noisy environment. We report an experimental simulation of environment-assisted coherent transport, using an engineered network of laser-written waveguides, with relative energies and inter-waveguide couplings tailored to yield the desired Hamiltonian. Controllable-strength decoherence is simulated by broadening the bandwidth of the input illumination, yielding a significant increase in transport efficiency relative to the narrowband case. We show integrated optics to be suitable for simulating specific target Hamiltonians as well as open quantum systems with controllable loss and decoherence.

  1. 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

    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...... 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...

  2. 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.

  3. 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

    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...... 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...... 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....

  4. A Semantic Context-Based Model for MobileWeb Services Access Control

    Directory of Open Access Journals (Sweden)

    Haibo Shen

    2011-02-01

    Full Text Available As mobile web services becomes more pervasive, applications based on mobile web services will need flexible access control mechanisms. Unlike traditional approaches based on the identity or role for access control, access decisions for these applications will depend on the combination of the required attributes of users and the contextual information. This paper proposes a semantic context-based access control model (called SCBAC to be applied in mobile web services environment by combining semantic web technologies with context-based access control mechanism. The proposed model is a context-centric access control solutions, context is the first-class principle that explicitly guides both policy specification and enforcement process. In order to handle context information in the model, this paper proposes a context ontology to represent contextual information and employ it in the inference engine. As well as, this paper specifies access control policies as rules over ontologies representing the concepts introduced in the SCBAC model, and uses semantic web rule language (SWRL to form policy rule and infer those rules by JESS inference engine. The proposed model can also be applied to context-aware applications.

  5. Adiabatic control of atomic dressed states for transport and sensing

    Science.gov (United States)

    Cooper, N. R.; Rey, A. M.

    2015-08-01

    We describe forms of adiabatic transport that arise for dressed-state atoms in optical lattices. Focusing on the limit of weak tunnel-coupling between nearest-neighbor lattice sites, we explain how adiabatic variation of optical dressing allows control of atomic motion between lattice sites: allowing adiabatic particle transport in a direction that depends on the internal state, and force measurements via spectroscopic preparation and readout. For uniformly filled bands these systems display topologically quantized particle transport. An implementation of the dressing scheme using optical transitions in alkaline-earth atoms is discussed as well as its favorable features for precise force sensing.

  6. WWW--Wealth, Weariness or Waste. Controlled Vocabulary and Thesauri in Support of Online Information Access.

    Science.gov (United States)

    Batty, David

    1998-01-01

    Discusses the problems of access to information in a machine-sensible environment, and the potential of modern library techniques to help in solving them. Explains how authors and publishers can make information more accessible by providing indexing information that uses controlled vocabulary, terms from a thesaurus, or other linguistic assistance…

  7. Human engineering considerations in designing a computerized controlled access security system

    International Nuclear Information System (INIS)

    This paper describes a human engineering effort in the design of a major security system upgrade at Lawrence Livermore National Laboratory. This upgrade was to be accomplished by replacing obsolete and difficult-to-man (i.e., multiple operator task actions required) security equipment and systems with a new, automated, computer-based access control system. The initial task was to assist the electronic and mechanical engineering staff in designing a computerized security access system too functionally and ergonomically accommodate 100% of the Laboratory user population. The new computerized access system was intended to control entry into sensitive exclusion areas by requiring personnel to use an entry booth-based system and/or a remote access control panel system. The primary user interface with the system was through a control panel containing a magnetic card reader, function buttons, LCD display, and push-button keypad

  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

    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...... 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...... Authentication and Capability based Access Control (IACAC) model with protocol evaluation and performance analysis. To protect IoT from man-in-the-middle, replay and denial of service (Dos) attacks, the concept of capability for access control is introduced. The novelty of this model is that, it presents...

  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. 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...... (c.f. GM03,Mos05,Ris13) and manual analysis of the overall effect and consequences of a large XACML policy set is a very daunting and time-consuming task. In this thesis we address the problem of understanding the semantics of access control policy language XACML, in particular XACML version 3.0. The...... main focus of this thesis is modelling and analysing access control policies in XACML 3.0. There are two main contributions in this thesis. First, we study and formalise XACML 3.0, in particular the Policy Decision Point (PDP). The concrete syntax of XACML is based on the XML format, while its standard...

  11. The RFID smart card management application for the hotel access control

    OpenAIRE

    Kreslin, Robert

    2011-01-01

    In this thesis we wanted to present the project that was made for a smaller hotel in Nova Gorica. The goal was to create an application for managing access control according to customer's wishes as well as to introduce the system into the existent infrastructure. The first step was to define what access control actually means. In broad terms it is divided into RFID – radio-frequency identification and biometric identification. Both have their strengths and their weaknesses. Next step was choo...

  12. 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.

  13. A New Access Control Scheme for Facebook-style Social Networks

    OpenAIRE

    Pang, Jun; Zhang, Yang

    2013-01-01

    The popularity of online social networks (OSNs) makes the protection of users' private information an important but scientifically challenging problem. In the literature, relationship-based access control schemes have been proposed to address this problem. However, with the dynamic developments of OSNs, we identify new access control requirements which cannot be fully captured by the current schemes. In this paper, we focus on public information in OSNs and treat it as a new dimension which u...

  14. 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...

  15. Structural controls on anomalous transport in fractured porous rock

    Science.gov (United States)

    Edery, Yaniv; Geiger, Sebastian; Berkowitz, Brian

    2016-07-01

    Anomalous transport is ubiquitous in a wide range of disordered systems, notably in fractured porous formations. We quantitatively identify the structural controls on anomalous tracer transport in a model of a real fractured geological formation that was mapped in an outcrop. The transport, determined by a continuum scale mathematical model, is characterized by breakthrough curves (BTCs) that document anomalous (or "non-Fickian") transport, which is accounted for by a power law distribution of local transition times ψ>(t>) within the framework of a continuous time random walk (CTRW). We show that the determination of ψ>(t>) is related to fractures aligned approximately with the macroscopic direction of flow. We establish the dominant role of fracture alignment and assess the statistics of these fractures by determining a concentration-visitation weighted residence time histogram. We then convert the histogram to a probability density function (pdf) that coincides with the CTRW ψ>(t>) and hence anomalous transport. We show that the permeability of the geological formation hosting the fracture network has a limited effect on the anomalous nature of the transport; rather, it is the fractures transverse to the flow direction that play the major role in forming the long BTC tail associated with anomalous transport. This is a remarkable result, given the complexity of the flow field statistics as captured by concentration transitions.

  16. 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.

  17. Demonstration of IP based control and management for a reconfigurable photonic access network

    NARCIS (Netherlands)

    Teune, Ronald; Roy, Rajeev; Etten, van Wim

    2008-01-01

    An implementation of control and management for a reconfigurable photonic access network is presented. An out of band control channel is used on which an IP communication is established to communicate with remote elements. A Headend based master controller communicates with a far end embedded proces

  18. 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...

  19. 75 FR 69791 - Risk Management Controls for Brokers or Dealers With Market Access

    Science.gov (United States)

    2010-11-15

    ... Exchange Commission 17 CFR Part 240 Risk Management Controls for Brokers or Dealers With Market Access... Regulations#0;#0; ] SECURITIES AND EXCHANGE COMMISSION 17 CFR Part 240 RIN 3235-AK53 Risk Management Controls.... The required financial risk management controls and supervisory procedures must be reasonably...

  20. Adaptive fuzzy-neural-network control for maglev transportation system.

    Science.gov (United States)

    Wai, Rong-Jong; Lee, Jeng-Dao

    2008-01-01

    A magnetic-levitation (maglev) transportation system including levitation and propulsion control is a subject of considerable scientific interest because of highly nonlinear and unstable behaviors. In this paper, the dynamic model of a maglev transportation system including levitated electromagnets and a propulsive linear induction motor (LIM) based on the concepts of mechanical geometry and motion dynamics is developed first. Then, a model-based sliding-mode control (SMC) strategy is introduced. In order to alleviate chattering phenomena caused by the inappropriate selection of uncertainty bound, a simple bound estimation algorithm is embedded in the SMC strategy to form an adaptive sliding-mode control (ASMC) scheme. However, this estimation algorithm is always a positive value so that tracking errors introduced by any uncertainty will cause the estimated bound increase even to infinity with time. Therefore, it further designs an adaptive fuzzy-neural-network control (AFNNC) scheme by imitating the SMC strategy for the maglev transportation system. In the model-free AFNNC, online learning algorithms are designed to cope with the problem of chattering phenomena caused by the sign action in SMC design, and to ensure the stability of the controlled system without the requirement of auxiliary compensated controllers despite the existence of uncertainties. The outputs of the AFNNC scheme can be directly supplied to the electromagnets and LIM without complicated control transformations for relaxing strict constrains in conventional model-based control methodologies. The effectiveness of the proposed control schemes for the maglev transportation system is verified by numerical simulations, and the superiority of the AFNNC scheme is indicated in comparison with the SMC and ASMC strategies. PMID:18269938

  1. An adaptive robust controller for time delay maglev transportation systems

    Science.gov (United States)

    Milani, Reza Hamidi; Zarabadipour, Hassan; Shahnazi, Reza

    2012-12-01

    For engineering systems, uncertainties and time delays are two important issues that must be considered in control design. Uncertainties are often encountered in various dynamical systems due to modeling errors, measurement noises, linearization and approximations. Time delays have always been among the most difficult problems encountered in process control. In practical applications of feedback control, time delay arises frequently and can severely degrade closed-loop system performance and in some cases, drives the system to instability. Therefore, stability analysis and controller synthesis for uncertain nonlinear time-delay systems are important both in theory and in practice and many analytical techniques have been developed using delay-dependent Lyapunov function. In the past decade the magnetic and levitation (maglev) transportation system as a new system with high functionality has been the focus of numerous studies. However, maglev transportation systems are highly nonlinear and thus designing controller for those are challenging. The main topic of this paper is to design an adaptive robust controller for maglev transportation systems with time-delay, parametric uncertainties and external disturbances. In this paper, an adaptive robust control (ARC) is designed for this purpose. It should be noted that the adaptive gain is derived from Lyapunov-Krasovskii synthesis method, therefore asymptotic stability is guaranteed.

  2. Plasma transport control and self-sustaining fusion reactor

    International Nuclear Information System (INIS)

    The possibility of a high performance/low cost fusion reactor concept which can simultaneously satisfy (1) high beta, (2) high bootstrap fraction (self-sustaining), and (3) high confinement is discussed. In CDX-U, a tokamak configuration was created and sustained solely by internally generated bootstrap currents, in which a seed current is created through a non-classical current diffusion process. Recent theoretical studies of MHD stability limits in spherical torus .g., the National Spherical Torus Experiment (NSTX) reduced a promising regime with stable beta of 45% and bootstrap current fraction of ≥99%. Since the bootstrap current is generated by the pressure gradient, to satisfy the needed current profile for MHD stable high beta regimes, it is essential to develop a means to control the pressure profile. It is suggested that the most efficient approach for pressure profile control is through a creation of transport barriers (localized regions of low plasma transport) in the plasma. As a tool for creating the core transport barrier, poloidal-sheared-flow generation by ion Bernstein waves (IBW) near the wave absorption region appears to be promising. In PBX-M, application of IBW power produced a high-quality internal transport barrier where the ion energy and particle transport became neoclassical in the barrier region. The observation is consistent with the IBW-induced-poloidal-sheared-flow model. An experiment is planned on TFTR to demonstrate this concept with D-T reactor-grade plasmas. For edge transport control, a method based on electron ripple injection (ERI), driven by electron cyclotron heating (ECH), is being developed on CDX-U. It is estimated that both the IBW and ERI methods can create a transport barrier in reactor-grade plasmas (e.g., ITER) with a relatively small amount of power (∼10 MW much-lt Pfusion)

  3. The new control system of HLS linac and transport line

    Institute of Scientific and Technical Information of China (English)

    LIU Gong-Fa; LI Wei-Min; LI Jing-Yi; LI Chuan; CHEN Li-Ping; BAO Xun; WANG Ji-Gang; XUAN Ke

    2005-01-01

    The new linac and transport line control system of Hefei Light Source (HLS) is a distributed control system based on EPICS (Experimental Physics and Industrial Control System). Industrial PC (IPC) is widely used as not only Input/Output Controller (IOC) but also device controller. Besides industrial PC, PLC and microcontroller are also used as device controllers. The software for industrial PC based device controller is developed based on VxWorks real-time operating system. The software for PLC and microcontroller are written with ladder software package and assemble language, respectively. PC with Linux and SUN workstation with Solaris are used as operator interfaces (OPI). High level control is made up of some EPICS tools and Tcl/Tk scripts.

  4. Controlled Spin Transport in Planar Systems Through Topological Exciton

    CERN Document Server

    Abhinav, Kumar

    2015-01-01

    It is shown that a charge-neutral spin-1 exciton, possibly realizable only in planar systems like graphene and topological insulators, can be effectively used for controlled spin transport in such media. The effect of quantum and thermal fluctuations yield a parametric excitation threshold for its realization. This planar exciton differs from the conventional ones, as it owes its existence to the topological Chern-Simons (CS) term. The parity and time-reversal violating CS term can arise from quantum effects in systems with parity-breaking mass-gap. The spinning exciton naturally couples to magnetic field, leading to the possibility of controlled spin transport. Being neutral, it is immune to a host of effect, which afflicts spin transport through charged fermions.

  5. Validation of Islet Transport From a Geographically Distant Isolation Center Enabling Equitable Access and National Health Service Funding of a Clinical Islet Transplant Program for England.

    Science.gov (United States)

    Aldibbiat, Ali; Huang, Guo Cai; Zhao, Min; Holliman, Graham N; Ferguson, Linda; Hughes, Stephen; Brigham, Ken; Wardle, Julie; Williams, Rob; Dickinson, Anne; White, Steven A; Johnson, Paul R V; Manas, Derek; Amiel, Stephanie A; Shaw, James A M

    2012-01-01

    Islet transplantation has become established as a successful treatment for type 1 diabetes complicated by recurrent severe hypoglycemia. In the UK access has been limited to a few centrally located units. Our goal was to validate a quality-assured system for safe/effective transport of human islets in the UK and to successfully undertake the first transplants with transported islets. Pancreases were retrieved from deceased donors in the north of England and transported to King's College London using two-layer method (TLM) or University of Wisconsin solution alone. Islets were isolated and transported back to Newcastle in standard blood transfusion or gas-permeable bags with detailed evaluation pre- and posttransport. In the preclinical phase, islets were isolated from 10 pancreases with mean yield of 258,000 islet equivalents. No significant differences were seen between TLM and University of Wisconsin solution organ preservation. A significant loss of integrity was demonstrated in islets shipped in gas-permeable bags, whereas sterility, number, purity, and viability were maintained in blood transfusion bags. Maintenance of secretory granules and glucose-stimulated insulin secretion was confirmed following transport. A Standard Operating Procedure enabling final pretransplant quality control from a simple side-arm sample was validated. Moreover, levels of insulin and cytokines in transport medium were low, enabling transplant without centrifugation/resuspension at the recipient site. Six clinical transplants of transported islets were undertaken in five recipients with 100% primary graft function and resolution of severe hypoglycemia. Safe and clinically effective islet transport has been established facilitating sustainable NHS funding of a clinical islet transplant program for the UK.

  6. 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...

  7. 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.

  8. Dynamic one-way traffic control in automated transportation systems

    NARCIS (Netherlands)

    Ebben, M; van der Zee, DJ

    2004-01-01

    In a project on underground freight transportation using Automated Guided Vehicles, single lanes for traffic in two directions are constructed to reduce infrastructure investment. Intelligent control rules are required to manage vehicle flows such, that collision is avoided and waiting times are min

  9. Effect of density control and impurity transport on internal transport barrier formation in tokamak plasma

    International Nuclear Information System (INIS)

    In future fusion reactors, density control, such as fueling by pellet injection, is an effective method to control the formation of the internal transport barrier (ITB) in reversed magnetic shear plasma, which can improve plasma performance. On the other hand, an operation with ITB can cause accumulation of impurities inside the core ITB region. We studied the relation between pellet injection and ITB formation and the effect of impurity transport on the core of ITB for tokamak plasmas by using the toroidal transport analysis linkage. For ITB formation, we showed that the pellet has to be injected beyond the position where the safety factor q takes the minimum value. We confirmed that the accumulation of impurities causes the attenuation of ITB owing to radiation loss inside the ITB region. Moreover, in terms of the divertor heat flux reduction by impurity gas, the line radiation loss is high for high-Z noble gas impurities, such as Kr, whereas factor Q decreases slightly. (author)

  10. Technical enforcement of european privacy legislation: an access control approach

    OpenAIRE

    Bekara, Kheira; Laurent, Maryline; Nguyen, Than Ha

    2012-01-01

    Until today, the protection of personal data is mainly left to the legislation by means of guidelines. This paper aims to increase the perceived control by users over their data by helping the user's agent to check the service requests conformity to the legislation. To do so, it discusses the main concepts involved in the legislative privacy principles, and deduces a privacy semantic information model. The proposed model focuses on the main concepts involved in legislative privacy principles....

  11. An Action-Based Fine-Grained Access Control Mechanism for Structured Documents and Its Application

    Directory of Open Access Journals (Sweden)

    Mang Su

    2014-01-01

    Full Text Available This paper presents an action-based fine-grained access control mechanism for structured documents. Firstly, we define a describing model for structured documents and analyze the application scenarios. The describing model could support the permission management on chapters, pages, sections, words, and pictures of structured documents. Secondly, based on the action-based access control (ABAC model, we propose a fine-grained control protocol for structured documents by introducing temporal state and environmental state. The protocol covering different stages from document creation, to permission specification and usage control are given by using the Z-notation. Finally, we give the implementation of our mechanism and make the comparisons between the existing methods and our mechanism. The result shows that our mechanism could provide the better solution of fine-grained access control for structured documents in complicated networks. Moreover, it is more flexible and practical.

  12. Accessible triple-phase boundary length: A performance metric to account for transport pathways in heterogeneous electrochemical materials

    Science.gov (United States)

    Nakajo, A.; Cocco, A. P.; DeGostin, M. B.; Peracchio, A. A.; Cassenti, B. N.; Cantoni, M.; Van herle, J.; Chiu, W. K. S.

    2016-09-01

    The performance of materials for electrochemical energy conversion and storage depends upon the number of electrocatalytic sites available for reaction and their accessibility by the transport of reactants and products. For solid oxide fuel/electrolysis cell materials, standard 3-D measurements such as connected triple-phase boundary (TPB) length and effective transport properties partially inform on how local geometry and network topology causes variability in TPB accessibility. A new measurement, the accessible TPB, is proposed to quantify these effects in detail and characterize material performance. The approach probes the reticulated pathways to each TPB using an analytical electrochemical fin model applied to a 3-D discrete representation of the heterogeneous structure provided by skeleton-based partitioning. The method is tested on artificial and real structures imaged by 3-D x-ray and electron microscopy. The accessible TPB is not uniform and the pattern varies depending upon the structure. Connected TPBs can be even passivated. The sensitivity to manipulations of the local 3-D geometry and topology that standard measurements cannot capture is demonstrated. The clear presence of preferential pathways showcases a non-uniform utilization of the 3-D structure that potentially affects the performance and the resilience to alterations due to degradation phenomena. The concepts presented also apply to electrochemical energy storage and conversion devices such as other types of fuel cells, electrolyzers, batteries and capacitors.

  13. TRBAC:基于信任的访问控制模型%TRBAC: Trust Based Access Control Model

    Institute of Scientific and Technical Information of China (English)

    刘武; 段海新; 张洪; 任萍; 吴建平

    2011-01-01

    访问控制是根据网络用户的身份或属性,对该用户执行某些操作或访问某些网络资源进行控制的过程.对现有访问控制模型进行分析,并针对其不足对RBAC模型进行了扩展,提出了基于信任的访问控制模型TRBAC(trust based access control model).该模型可以提供更加安全、灵活以及细粒度的动态访问授权机制,从而提高授权机制的安全性与可靠性.%Access control is a process which controls users to execute some operations or access some network resources according to the users' identity or attribution. The discretionary access control and mandatory access control are two main access control modes which are broadly used in secure operating systems. Discretionary access control is based on user identity and/or groups and mandatory access control is usually based on sensitivity labels. Neither of these two modes can completely satisfy the requirements of all access control. Discretionary access control is too loose to restrict the propagation of privileges while mandatory access control is too rigid to use flexibly. This paper analyzes current access control models, and extends the RBAC (role based access control) model aiming at its deficiency, and based on which we propose a trust based access control model (TRBAC). The TRBAC model can provide more security, flexible and fine-grained dynamic access control mechanism, and therefore improve both the security and the reliability of authorization mechanism.

  14. 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...

  15. Sistemas de Control en el Transporte de productos Perecederos

    OpenAIRE

    Ruiz García, Luis; Barreiro Elorza, Pilar; Ruiz-Altisent, Margarita

    2009-01-01

    Los productos alimentarios perecederos tales como hortalizas, frutas, carne o pescado requieren transporte refrigerado. El control de la calidad y supervisión de los productos durante su transporte y distribución es de gran importancia, siendo el mayor reto asegurar una cadena de frio continua desde el productor hasta el consumidor. Entre las diferentes tecnologías que se pueden utilizar para monitorizar, destacan las tecnologías de sensórica inalámbrica que pueden ser de dos tipos: RFID...

  16. Advanced Transport Operating System (ATOPS) control display unit software description

    Science.gov (United States)

    Slominski, Christopher J.; Parks, Mark A.; Debure, Kelly R.; Heaphy, William J.

    1992-01-01

    The software created for the Control Display Units (CDUs), used for the Advanced Transport Operating Systems (ATOPS) project, on the Transport Systems Research Vehicle (TSRV) is described. Module descriptions are presented in a standardized format which contains module purpose, calling sequence, a detailed description, and global references. The global reference section includes subroutines, functions, and common variables referenced by a particular module. The CDUs, one for the pilot and one for the copilot, are used for flight management purposes. Operations performed with the CDU affects the aircraft's guidance, navigation, and display software.

  17. Preface: cardiac control pathways: signaling and transport phenomena.

    Science.gov (United States)

    Sideman, Samuel

    2008-03-01

    Signaling is part of a complex system of communication that governs basic cellular functions and coordinates cellular activity. Transfer of ions and signaling molecules and their interactions with appropriate receptors, transmembrane transport, and the consequent intracellular interactions and functional cellular response represent a complex system of interwoven phenomena of transport, signaling, conformational changes, chemical activation, and/or genetic expression. The well-being of the cell thus depends on a harmonic orchestration of all these events and the existence of control mechanisms that assure the normal behavior of the various parameters involved and their orderly expression. The ability of cells to sustain life by perceiving and responding correctly to their microenvironment is the basis for development, tissue repair, and immunity, as well as normal tissue homeostasis. Natural deviations, or human-induced interference in the signaling pathways and/or inter- and intracellular transport and information transfer, are responsible for the generation, modulation, and control of diseases. The present overview aims to highlight some major topics of the highly complex cellular information transfer processes and their control mechanisms. Our goal is to contribute to the understanding of the normal and pathophysiological phenomena associated with cardiac functions so that more efficient therapeutic modalities can be developed. Our objective in this volume is to identify and enhance the study of some basic passive and active physical and chemical transport phenomena, physiological signaling pathways, and their biological consequences.

  18. A Group-oriented Access Control Scheme for P2P Networks

    OpenAIRE

    Wang Xiaoming; Cheng Fan

    2011-01-01

    A group-oriented access control scheme is proposed for P2P (peer to peer) networks. In the proposed scheme, authentication control, admission control and revocation control are used in order to provide security services for P2P networks. Moreover, the proposed scheme can simply and efficient establish share key between two members without interactions, therefore it can perform secure communications with them. The analysis of security and performance shows that the proposed scheme not only can...

  19. A novel decentralized hierarchical access control scheme for the medical scenario

    DEFF Research Database (Denmark)

    Eskeland, Sigurd; Prasad, Neeli R.

    2006-01-01

    Electronic patient records contains highly personal and confidential information that it is essential to keep private. Thus, only the medical professionals providing care to a patient should access the patient record of the concerning patient. As personal medical data can be considered...... 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......, the hierarchical aspects of teams are taken into account so that the modules of the patient record are to be accessed according to the individual privileges of the medical professionals of the team. Thus, more privileged users obtain larger portions of the data than less privileged users....

  20. A novel decentralized hierarchical access control scheme for the medical scenario

    DEFF Research Database (Denmark)

    Eskeland, Sigurd; Prasad, Neeli R.

    2006-01-01

    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, the......Electronic patient records contains highly personal and confidential information that it is essential to keep private. Thus, only the medical professionals providing care to a patient should access the patient record of the concerning patient. As personal medical data can be considered to be the...... hierarchical aspects of teams are taken into account so that the modules of the patient record are to be accessed according to the individual privileges of the medical professionals of the team. Thus, more privileged users obtain larger portions of the data than less privileged users....

  1. Access to the Birth Control Pill and the Career Plans of Young Men and Women

    DEFF Research Database (Denmark)

    Steingrimsdottir, Herdis

    The paper explores the effect of unrestricted access to the birth control pill on young people’s career plans, using annual surveys of college freshmen from 1968 to 1980. In particular it addresses the question of who was affected by the introduction of the birth control pill by looking at career...... access to the pill is found to be on non-white students, both among men and women. The paper uses Census Data to compare the changes in career plans to actual changes in labor market outcomes. When looking at the actual career outcomes, early access to the pill affects both men and women - shifting...... plans of both men and women, and by separating the effect by level of academic ability, race and family income. The results show that unrestricted access to the pill caused high ability women to move towards occupations with higher wages, higher occupational prestige scores and higher male ratios...

  2. A Fine-Grained Data Access Control System in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Boniface K. Alese

    2015-12-01

    Full Text Available The evolving realities of Wireless Sensor Network (WSN deployed to various terrain of life require serving multiple applications. As large amount of sensed data are distributed and stored in individual sensors nodes, the illegal access to these sensitive data can be devastating. Consequently, data insecurity becomes a big concern. This study, therefore, proposes a fine-grained access control system which only requires the right set of users to access a particular data, based on their access privileges in the sensor networks. It is designed using Priccess Protocol with Access policy formulation adopting the principle of Bell Lapadula model as well as Attribute-Based Encryption (ABE to control access to sensor data. The functionality of the proposed system is simulated using Netbeans. The performance analysis of the proposed system using execution time and size of the key show that the higher the key size, the harder it becomes for the attacker to hack the system. Additionally, the time taken for the proposed work is lesser which makes the work faster than the existing work. Consequently, a well secure interactive web-based application that could facilitates the field officers access to stored data in safe and secure manner is developed.

  3. An advanced control system for a next generation transport aircraft

    Science.gov (United States)

    Rising, J. J.; Davis, W. J; Grantham, W. D.

    1983-01-01

    The use of modern control theory to develop a high-authority stability and control system for the next generation transport aircraft is described with examples taken from work performed on an advanced pitch active control system (PACS). The PACS was configured to have short-period and phugoid modes frequency and damping characteristics within the shaded S-plane areas, column force gradients with set bounds and with constant slope, and a blended normal-acceleration/pitch rate time history response to a step command. Details of the control law, feedback loop, and modal control syntheses are explored, as are compensation for the feedback gain, the deletion of the velocity signal, and the feed-forward compensation. Scheduling of the primary and secondary gains are discussed, together with control law mechanization, flying qualities analyses, and application on the L-1011 aircraft.

  4. Steganography-based access control to medical data hidden in electrocardiogram.

    Science.gov (United States)

    Mai, Vu; Khalil, Ibrahim; Ibaida, Ayman

    2013-01-01

    Steganographic techniques allow secret data to be embedded inside another host data such as an image or a text file without significant changes to the quality of the host data. In this research, we demonstrate how steganography can be used as the main mechanism to build an access control model that gives data owners complete control to their sensitive cardiac health information hidden in their own Electrocardiograms. Our access control model is able to protect the privacy of users, the confidentiality of medical data, reduce storage space and make it more efficient to upload and download large amount of data.

  5. Steganography-based access control to medical data hidden in electrocardiogram.

    Science.gov (United States)

    Mai, Vu; Khalil, Ibrahim; Ibaida, Ayman

    2013-01-01

    Steganographic techniques allow secret data to be embedded inside another host data such as an image or a text file without significant changes to the quality of the host data. In this research, we demonstrate how steganography can be used as the main mechanism to build an access control model that gives data owners complete control to their sensitive cardiac health information hidden in their own Electrocardiograms. Our access control model is able to protect the privacy of users, the confidentiality of medical data, reduce storage space and make it more efficient to upload and download large amount of data. PMID:24109934

  6. A hybrid medium access control for convergence of broadband wireless and wireline ATM networks

    DEFF Research Database (Denmark)

    Liu, Hong; Gliese, Ulrik Bo; Dittmann, Lars

    2000-01-01

    In this paper, we propose a hybrid medium access control protocol for supporting broadband integrated services in the wireless ATM networks. The integrated services include CBR, VBR and ABR traffic varying from low bit-rate to very high bit-rate. The proposed protocol is an excellent compromise...... of contention, reservation and polling access techniques based on the dynamic TDMA system. Extensive simulation results using realistic data traffic sources, show that the proposed medium access scheme may provide QoS guarantees to different ATM traffic including the realistic MPEG video traces with low cell...

  7. On the Need of Novel Medium Access Control Schemes for Network Coding enabled Wireless Mesh Networks

    DEFF Research Database (Denmark)

    Paramanathan, Achuthan; Pahlevani, Peyman; Roetter, Daniel Enrique Lucani;

    2013-01-01

    This paper advocates for a new Medium Access Control (MAC) strategy for wireless meshed networks by identifying overload scenarios in order to provide additional channel access priority to the relay. The key behind our MAC protocol is that the relay will adjust its back off window size according...... that network coding will improve the throughput in such systems, but our novel medium access scheme improves the performance in the cross topology by another 66 % for network coding and 150 % for classical forwarding in theory. These gains translate in a theoretical gain of 33 % of network coding over...

  8. Analysis of Decision Factors for the Application of Information Access Controls within the Organization

    Science.gov (United States)

    Foerster, Carl A.

    2013-01-01

    The application of access controls on internal information necessarily impacts the availability of that information for sharing inside the enterprise. The decisions establishing the degree of control are a crucial first step to balance the requirements to protect and share. This research develops a set of basic decision factors and examines other…

  9. SparkXS: efficient access control for intelligent and large-scale streaming data applications

    OpenAIRE

    Preuveneers, Davy; Joosen, Wouter

    2015-01-01

    The exponential data growth in intelligent environments fueled by the Internet of Things is not only a major push behind distributed programming frameworks for big data, it also magnifies security and privacy concerns about unauthorized access to data. The huge diversity and the streaming nature of data raises the demand for new enabling technologies for scalable access control that can deal with the growing velocity, volume and variety of volatile data. This paper presents SparkXS, ...

  10. A Model-driven Role-based Access Control for SQL Databases

    OpenAIRE

    Raimundas Matulevičius; Henri Lakk

    2015-01-01

    Nowadays security has become an important aspect in information systems engineering. A mainstream method for information system security is Role-based Access Control (RBAC), which restricts system access to authorised users. While the benefits of RBAC are widely acknowledged, the implementation and administration of RBAC policies remains a human intensive activity, typically postponed until the implementation and maintenance phases of system development. This deferred security engineering app...

  11. Design of Active Queue Management for Robust Control on Access Router for Heterogeneous Networks

    Directory of Open Access Journals (Sweden)

    Åhlund Christer

    2011-01-01

    Full Text Available The Internet architecture is a packet switching technology that allows dynamic sharing of bandwidth among different flows with in an IP network. Packets are stored and forwarded from one node to the next until reaching their destination. Major issues in this integration are congestion control and how to meet different quality of service requirements associated with various services. In other words streaming media quality degrades with increased packet delay and jitter caused by network congestion. To mitigate the impact of network congestion, various techniques have been used to improve multimedia quality and one of those techniques is Active Queue Management (AQM. Access routers require a buffer to hold packets during times of congestion. A large buffer can absorb the bursty arrivals, and this tends to increase the link utilizations but results in higher queuing delays. Traffic burstiness has a considerable negative impact on network performance. AQM is now considered an effective congestion control mechanism for enhancing transport protocol performance over wireless links. In order to have good link utilization, it is necessary for queues to adapt to varying traffic loads. This paper considers a particular scheme which is called Adaptive AQM (AAQM and studies its performance in the presence of feedback delays and its ability to maintain a small queue length as well as its robustness in the presence of traffic burstiness. The paper also presents a method based on the well-known Markov Modulated Poisson Process (MPP to capture traffic burstiness and buffer occupancy. To demonstrate the generality of the presented method, an analytic model is described and verified by extensive simulations of different adaptive AQM algorithms. The analysis and simulations show that AAQM outperforms the other AQMs with respect to responsiveness and robustness.

  12. Subsurface Access, Characterization, Acquisition, Transport, Storage and Delivery in Microgravity Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will develop geotechnical measurements, sample extraction and transport equipment for subsurface regolith on NEOs, asteroids, moons and planets,...

  13. 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

    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...... farm controller. The controller attempts to reduce fatigue on the wind turbine, which is used as a measure of the controller performance. Via simulation analysis, we show the degradation of the controller performance when subject to network delays. We analyse different access strategies useable...... by the controller to gather sensor information and and quantitatively characterize the impact of these access strategies on the controller performance...

  14. Traffic improvement and transportation pollution control in Xiamen

    Energy Technology Data Exchange (ETDEWEB)

    Dongxing Yuan; Zilin, Wu

    1996-12-31

    in this paper, the urban traffic improvement and transportation control in Xiamen are highlighted. Xiamen is a port city and an economical special zone of China. As the economy grows, the transportation is developing dramatically and becoming the key for further economic development. The air quality is threatened by the rapid growth of the vehicles in the city. The most urgent task in improving urban traffic is to establish a sound traffic system. The municipal government takes great effort to improve the traffic condition, as well as to reduce green house gases and protect air environment. Some management and technical measures are carried out. Those management measures are mainly as follows: (1) systematic planning of the city arrangement and city functional division, and integrated planning of the urban roads system, (2) putting great emphasis on tail gas monitoring and management, and (3) establishing optimized utilization of motor vehicles. Those included in the main technical measures are (1) making the roads clear, (2) enlarging traffic capacity, and (3) developing the public transport. The most urgent task in improving urban traffic is to establish a sound traffic system. The city municipal government and Transportation Management Bureau plan to make a series of reforms to improve the urban traffic condition, such as building high quality road around the city, reducing the number of one way roads and replacing gasoline buses with electric buses. An optimized traffic system of Xiamen, taking public transport as the main means, is the key to meet the needs of both traffic improvement and urban transportation pollution control.

  15. MAAC: a software tool for user authentication and access control to the electronic patient record in an open distributed environment

    Science.gov (United States)

    Motta, Gustavo H.; Furuie, Sergio S.

    2004-04-01

    Designing proper models for authorization and access control for the electronic patient record (EPR) is essential to wide scale use of the EPR in large health organizations. This work presents MAAC (Middleware for Authentication and Access Control), a tool that implements a contextual role-based access control (RBAC) authorization model. RBAC regulates user"s access to computers resources based on their organizational roles. A contextual authorization uses environmental information available at access-request time, like user/patient relationship, in order to decide whether a user has the right to access an EPR resource. The software architecture where MAAC is implemented uses Lightweight Directory Access Protocol, Java programming language and the CORBA/OMG standards CORBA Security Service and Resource Access Decision Facility. With those open and distributed standards, heterogeneous EPR components can request user authentication and access authorization services in a unified and consistent fashion across multiple platforms.

  16. Sec16 alternative splicing dynamically controls COPII transport efficiency.

    Science.gov (United States)

    Wilhelmi, Ilka; Kanski, Regina; Neumann, Alexander; Herdt, Olga; Hoff, Florian; Jacob, Ralf; Preußner, Marco; Heyd, Florian

    2016-08-05

    The transport of secretory proteins from the endoplasmic reticulum (ER) to the Golgi depends on COPII-coated vesicles. While the basic principles of the COPII machinery have been identified, it remains largely unknown how COPII transport is regulated to accommodate tissue- or activation-specific differences in cargo load and identity. Here we show that activation-induced alternative splicing of Sec16 controls adaptation of COPII transport to increased secretory cargo upon T-cell activation. Using splice-site blocking morpholinos and CRISPR/Cas9-mediated genome engineering, we show that the number of ER exit sites, COPII dynamics and transport efficiency depend on Sec16 alternative splicing. As the mechanistic basis, we suggest the C-terminal Sec16 domain to be a splicing-controlled protein interaction platform, with individual isoforms showing differential abilities to recruit COPII components. Our work connects the COPII pathway with alternative splicing, adding a new regulatory layer to protein secretion and its adaptation to changing cellular environments.

  17. Elevated expression of metal transporter genes in three accessions of the metal hyperaccumulator Thlaspi caerulescens

    NARCIS (Netherlands)

    Gonçalves Leite de Assunção, A.; Da Costa Martins, P.; Folter, de S.; Vooijs, R.; Aarts, M.G.M.

    2001-01-01

    Heavy metal hyperaccumulation in plants is an intriguing and poorly understood phenomenon. Transmembrane metal transporters are assumed to play a key role in this process. We describe the cloning and isolation of three zinc transporter cDNAs from the Zn hyperaccumulator Thlaspi caerulescens. The ZTP

  18. 1-Methylpyridinium-4-(4-phenylmethanethiosulfonate) iodide, MTS-MPP+, a novel scanning cysteine accessibility method (SCAM) reagent for monoamine transporter studies

    OpenAIRE

    Gallardo-Godoy, Alejandra; Torres-Altoro, Melissa I.; White, Kellie J.; Barker, Eric L.; Nichols, David E.

    2006-01-01

    A novel substituted cysteine accessibility method (SCAM) reagent was developed for monoamine uptake transporters. The new reagent, MTS-MPP+, was a derivative of the neurotoxin and transporter substrate MPP+. MTS-MPP+ labeled cysteine residues introduced into the serotonin transporter protein. Although it did not prove to be a substrate, as is MPP+, it appears to label cysteine residues lining the permeation pore of the transporter more readily than currently-available nonspecific SCAM reagents.

  19. Low temperature carrier transport properties in isotopically controlled germanium

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, K.

    1994-12-01

    Investigations of electronic and optical properties of semiconductors often require specimens with extremely homogeneous dopant distributions and precisely controlled net-carrier concentrations and compensation ratios. The previous difficulties in fabricating such samples are overcome as reported in this thesis by growing high-purity Ge single crystals of controlled {sup 75}Ge and {sup 70}Ge isotopic compositions, and doping these crystals by the neutron transmutation doping (NTD) technique. The resulting net-impurity concentrations and the compensation ratios are precisely determined by the thermal neutron fluence and the [{sup 74}Ge]/[{sup 70}Ge] ratios of the starting Ge materials, respectively. This method also guarantees unprecedented doping uniformity. Using such samples the authors have conducted four types of electron (hole) transport studies probing the nature of (1) free carrier scattering by neutral impurities, (2) free carrier scattering by ionized impurities, (3) low temperature hopping conduction, and (4) free carrier transport in samples close to the metal-insulator transition.

  20. 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...... 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. This chapter presents...... the Capability-based Context Aware Access Control (CCAAC) model including the authority delegation method, along with specification and protocol evaluation intended for federated Machine-to-Machine (M2M)/IoT. By using the identity and capability-based access control approach together with the contextual...

  1. The open access and the natural gas ducts: transport and distribution; O livre acesso e os dutos de gas natural: transporte e distribuicao

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, Mariana de; Xavier, Yanko Marcius de Alencar [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2008-07-01

    The present research, attempting for the economic relevance of the natural gas sector, for the lack of a law that disciplines it and, still, for the structural question of the natural gas ducts activities; it analyzes, in a comparative way, the monopoly of the natural gas ducts activities and the mechanisms of competition chosen to brighten up it: the open access and the by pas. The transport and the distribution of the natural gas are really similar, but the ways to insert the competition in its areas are not. (author)

  2. A Cache Considering Role-Based Access Control and Trust in Privilege Management Infrastructure

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shaomin; WANG Baoyi; ZHOU Lihua

    2006-01-01

    PMI(privilege management infrastructure) is used to perform access control to resource in an E-commerce or E-government system. With the ever-increasing need for secure transaction, the need for systems that offer a wide variety of QoS (quality-of-service) features is also growing. In order to improve the QoS of PMI system, a cache based on RBAC(Role-based Access Control) and trust is proposed. Our system is realized based on Web service. How to design the cache based on RBAC and trust in the access control model is described in detail. The algorithm to query role permission in cache and to add records in cache is dealt with. The policy to update cache is introduced also.

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

    DEFF Research Database (Denmark)

    Nagarajan, Anand; Jensen, Christian D.

    2010-01-01

    The electrical power infrastructure is facing a transition from a largely centralised distribution infrastructure with a few large power plants to an increasingly distributed infrastructure that must incorporate privately owned and operated power generation units based on fuel cells or sustainable...... 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...

  4. 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.

  5. Estimation of Medium Access Control Layer Packet Delay Distribution for IEEE 802.11

    Directory of Open Access Journals (Sweden)

    Hatm Alkadeki

    2013-12-01

    Full Text Available The most important standard in wireless local area networks is IEEE 802.11. This is why much of the research work for the enhancement of wireless network is usually based on the behavior of IEEE 802.11 protocol. However, some of the ways in which IEEE 802.11 medium access control layer behaves is still unreliable to guarantee quality of service. For instance , medium access control layer packet delay, jitter and packet loss rate still remain a challenge. The main objective of this research is to propose an accurate estimation of the medium access control layer packet delay distribution for IEEE 802.11. This estimation considers the differences between busy probability and collision probability. These differences are employed to achieve a mo re accurate estimation. Finally, the proposed model and simulation are implemented and validated - using MATLAB program for the purpose of simulation, and Maple program to undertake the calculation of the equations.

  6. Cognitive radio networks medium access control for coexistence of wireless systems

    CERN Document Server

    Bian, Kaigui; Gao, Bo

    2014-01-01

    This book gives a comprehensive overview of the medium access control (MAC) principles in cognitive radio networks, with a specific focus on how such MAC principles enable different wireless systems to coexist in the same spectrum band and carry out spectrum sharing.  From algorithm design to the latest developments in the standards and spectrum policy, readers will benefit from leading-edge knowledge of how cognitive radio systems coexist and share spectrum resources.  Coverage includes cognitive radio rendezvous, spectrum sharing, channel allocation, coexistence in TV white space, and coexistence of heterogeneous wireless systems.   • Provides a comprehensive reference on medium access control (MAC)-related problems in the design of cognitive radio systems and networks; • Includes detailed analysis of various coexistence problems related to medium access control in cognitive radio networks; • Reveals novel techniques for addressing the challenges of coexistence protocol design at a higher level ...

  7. Photonic transport control by spin-optical disordered metasurface

    OpenAIRE

    Veksler, Dekel; Maguid, Elhanan; Ozeri, Dror; Shitrit, Nir; Kleiner, Vladimir; Hasman, Erez

    2014-01-01

    Photonic metasurfaces are ultrathin electromagnetic wave-molding metamaterials providing the missing link for the integration of nanophotonic chips with nanoelectronic circuits. An extra twist in this field originates from spin-optical metasurfaces providing the photon spin (polarization helicity) as an additional degree of freedom in light-matter interactions at the nanoscale. Here we report on a generic concept to control the photonic transport by disordered (random) metasurfaces with a cus...

  8. Molecular assemblies that control rhodopsin transport to the cilia

    OpenAIRE

    Deretic, Dusanka; Jing WANG

    2012-01-01

    This review will focus on the conserved molecular mechanisms for the specific targeting of rhodopsin and rhodopsin-like sensory receptors to the primary cilia. We will discuss the molecular assemblies that control the movement of rhodopsin from the central sorting station of the cell, the trans-Golgi network (TGN), into membrane-enclosed rhodopsin transport carriers (RTCs), and their delivery to the primary cilia and the cilia-derived sensory organelles, the rod outer segments (ROS). Recent s...

  9. Control of intracellular heme levels: Heme transporters and Heme oxygenases

    OpenAIRE

    Khan, Anwar A.; Quigley, John G.

    2011-01-01

    Heme serves as a co-factor in proteins involved in fundamental biological processes including oxidative metabolism, oxygen storage and transport, signal transduction and drug metabolism. In addition, heme is important for systemic iron homeostasis in mammals. Heme has important regulatory roles in cell biology, yet excessive levels of intracellular heme are toxic; thus, mechanisms have evolved to control the acquisition, synthesis, catabolism and expulsion of cellular heme. Recently, a number...

  10. Active flow control systems architectures for civil transport aircraft

    OpenAIRE

    Jabbal, M; Liddle, SC; Crowther, WJ

    2010-01-01

    Copyright @ 2010 American Institute of Aeronautics and Astronautics This paper considers the effect of choice of actuator technology and associated power systems architecture on the mass cost and power consumption of implementing active flow control systems on civil transport aircraft. The research method is based on the use of a mass model that includes a mass due to systems hardware and a mass due to the system energy usage. An Airbus A320 aircraft wing is used as a case-study applicatio...

  11. Consistency maintenance for constraint in role-based access control model

    Institute of Scientific and Technical Information of China (English)

    韩伟力; 陈刚; 尹建伟; 董金祥

    2002-01-01

    Constraint is an important aspect of role-based access control and is sometimes argued to be the principal motivation for role-based access control (RBAC). But so far few authors have discussed consistency maintenance for constraint in RBAC model. Based on researches of constraints among roles and types of inconsistency among constraints, this paper introduces corresponding formal rules, rule-based reasoning and corresponding methods to detect, avoid and resolve these inconsistencies. Finally, the paper introduces briefly the application of consistency maintenance in ZD-PDM, an enterprise-oriented product data management (PDM) system.

  12. Consistency maintenance for constraint in role-based access control model

    Institute of Scientific and Technical Information of China (English)

    韩伟力; 陈刚; 尹建伟; 董金祥

    2002-01-01

    Constraint is an important aspect of role-based access control and is sometimes argued to be the principal motivation for role-based access control (RBAC). But so far'few authors have discussed consistency maintenance for constraint in RBAC model. Based on researches of constraints among roles and types of inconsistency among constraints, this paper introduces correaponding formal rules, rulebased reasoning and corresponding methods to detect, avoid and resolve these inconsistencies. Finally,the paper introduces briefly the application of consistency maintenance in ZD-PDM, an enterprise-ori-ented product data management (PDM) system.

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

    International Nuclear Information System (INIS)

    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. (general)

  14. An IEEE 802.3 Compatible Real Time Medium Access Control with Length-based Priority

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new medium access control method is proposed over the predominant Ethernet broadcast channel. Taking advantages of intrinsic variable length characteristic of standard Ethernet frame, message-oriented dynamic priority mechanism is established. Prioritized medium access control operates under a so-called block mode in event of collisions.High priority messages have a chance to preempt block status incurred by low priority ones. By this means, the new MAC provides a conditional deterministic real time performance beyond a statistical one. Experiments demonstrate effectiveness and attractiveness of the proposed scheme. Moreover, this new MAC is completely compatible with IEEE802.3.

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

    OpenAIRE

    Wen-Jye Shyr; Te-Jen Su; Chia-Ming Lin

    2013-01-01

    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 equ...

  16. Converged wireline and wireless signal transport over optical fibre access links

    DEFF Research Database (Denmark)

    Tafur Monroy, Idelfonso; Prince, Kamau; Osadchiy, Alexey Vladimirovich;

    2009-01-01

    This article reviews emerging trends in converged optical-wireless communication systems and outline the role that photonic technologies are playing in making the vision of a wireline-wireless converged signal transport network a reality....

  17. Volume transport data from a submarine cable in the Florida Strait in 2014 (NODC Accession 0125429)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily mean and raw voltage volume transport data of the Florida Current collected with a submarine cable spanning from South Florida to the Grand Bahama Island in...

  18. Volume transport data from a submarine cable in the Florida Strait from 2015 (NCEI Accession 0140278)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily mean and raw voltage volume transport data of the Florida Current collected with a submarine cable spanning from South Florida to the Grand Bahama Island in...

  19. Volume transport data from a submarine cable in the Florida Strait in 2013 (NODC Accession 0115895)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily mean and raw voltage volume transport data of the Florida Current collected with a submarine cable spanning from South Florida to the Grand Bahama Island in...

  20. Volume transport data from a submarine cable in the Florida Strait in 2012 (NODC Accession 0108045)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Daily mean and raw voltage volume transport data of the Florida Current collected with a submarine cable spanning from South Florida to the Grand Bahama Island in...

  1. Protein-based microhydraulic transport for controllable actuation

    Science.gov (United States)

    Sundaresan, Vishnu Baba; Leo, Donald J.

    2006-03-01

    Plants have the ability to develop large mechanical force from chemical energy available with bio-fuels. The energy released by the cleavage of a terminal phosphate ion during the hydrolysis of a bio- fuel assists the transport of ions and fluids in cellular homeostasis. Materials that develop pressure and hence strain similar to the response of plants to an external stimuli are classified as nastic materials. Calculations for controlled actuation of an active material inspired by biological transport mechanism demonstrated the feasibility of developing such a material with actuation energy densities on the order of 100 kJ/m 3. The mathematical model for a simplified proof of concept actuator referred to as micro hydraulic actuator uses ion transporters extracted from plants reconstituted on a synthetic bilayer lipid membrane (BLM). Thermodynamic model of the concept actuator predicted the ability to develop 5 percent normalized deformation in thickness of the micro- hydraulic actuator. Controlled fluid transport through AtSUT4 (Proton-sucrose co-transporter from Arabidopsis thaliana) reconstituted on a 1-Palmitoyl-2-Oleoyl-sn-Glycero-3-[Phospho-L- Serine] (Sodium Salt) (POPS), 1-Palmitoyl-2-Oleoyl-sn-Glycero-3- Phosphoethanolamine (POPE) BLM on a porous lead silicate glass plate (50μm with 61μm pitch) was driven by proton gradient. Bulk fluid flux of 1.2 μl/min was observed for each microliter of AtSUT4 transporter suspension (16.6 mg/ml in pH7.0 medium) reconstituted on the BLM. The flux rate is observed to be dependent on the concentration of sucrose present in pH4 buffer. Flux rate of 10 μl/min is observed for 5 mM sucrose in the first 10 minutes. The observed flux scales linearly with BLM area and the amount of proteins reconstituted on the lipid membrane. This article details the next step in the development of the micro hydraulic actuator - fluid transport driven by exergonic Adenosine triphosphate (ATP) hydrolysis reaction in the presence of ATP

  2. 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.

  3. Performance Evaluation of Virtualization Techniques for Control and Access of Storage Systems in Data Center Applications

    Science.gov (United States)

    Ahmadi, Mohammad Reza

    2013-09-01

    Virtualization is a new technology that creates virtual environments based on the existing physical resources. This article evaluates effect of virtualization techniques on control servers and access method in storage systems [1, 2]. In control server virtualization, we have presented a tile based evaluation based on heterogeneous workloads to compare several key parameters and demonstrate effectiveness of virtualization techniques. Moreover, we have evaluated the virtualized model using VMotion techniques and maximum consolidation. In access method, we have prepared three different scenarios using direct, semi-virtual, and virtual attachment models. We have evaluated the proposed models with several workloads including OLTP database, data streaming, file server, web server, etc. Results of evaluation for different criteria confirm that server virtualization technique has high throughput and CPU usage as well as good performance with noticeable agility. Also virtual technique is a successful alternative for accessing to the storage systems especially in large capacity systems. This technique can therefore be an effective solution for expansion of storage area and reduction of access time. Results of different evaluation and measurements demonstrate that the virtualization in control server and full virtual access provide better performance and more agility as well as more utilization in the systems and improve business continuity plan.

  4. Single-Walled Carbon Nanotubes Acting as Controllable Transport Channels

    Institute of Scientific and Technical Information of China (English)

    HUANG Bo-Da; XIA Yue-Yuan; ZHAO Ming-Wen; LI Feng; LIU Xiang-Dong; JI Yan-Ju; SONG Chen; TAN Zhen-Yu; LIU Hui

    2004-01-01

    @@ The motion and equilibrium distribution of water molecules adsorbed inside neutral and negatively charged singlewalled carbon nanotubes (SWNTs) have been studied using molecular dynamics simulations (MDSs) at room temperature based on CHARMM (Chemistry at HARvard Molecular Mechanics) potential parameters. We find that water molecules have a conspicuous electropism phenomenon and regular tubule patterns inside and outside the charged tube wall. The analyses of the motion behaviour of water molecules in the radial and axial directions show that by charging the SWNT, the adsorption efficiency is greatly enhanced, and the electric field produced by the charged SWNTs prevents water molecules from flowing out of the nanotube. However, water molecules can travel through the neutral SWNT in a fluctuating manner. This indicates that by electrically charging and uncharging the SWNTs, one can control the adsorption and transport behaviour of polar molecules in SWNTs for using as a stable storage medium or long transport channels. The transport velocity can be tailored by changing the charge on the SWNTs, which may have a further application as modulatable transport channels.

  5. Accessibility to tuberculosis control services and tuberculosis programme performance in southern Ethiopia

    Directory of Open Access Journals (Sweden)

    Mesay Hailu Dangisso

    2015-11-01

    Full Text Available Background: Despite the expansion of health services and community-based interventions in Ethiopia, limited evidence exists about the distribution of and access to health facilities and their relationship with the performance of tuberculosis (TB control programmes. We aim to assess the geographical distribution of and physical accessibility to TB control services and their relationship with TB case notification rates (CNRs and treatment outcome in the Sidama Zone, southern Ethiopia. Design: We carried out an ecological study to assess physical accessibility to TB control facilities and the association of physical accessibility with TB CNRs and treatment outcome. We collected smear-positive pulmonary TB (PTB cases treated during 2003–2012 from unit TB registers and TB service data such as availability of basic supplies for TB control and geographic locations of health services. We used ArcGIS 10.2 to measure the distance from each enumeration location to the nearest TB control facilities. A linear regression analysis was employed to assess factors associated with TB CNRs and treatment outcome. Results: Over a decade the health service coverage (the health facility–to-population ratio increased by 36% and the accessibility to TB control facilities also improved. Thus, the mean distance from TB control services was 7.6 km in 2003 (ranging from 1.8 to 25.5 km between kebeles (the smallest administrative units and had decreased to 3.2 km in 2012 (ranging from 1.5 to 12.4 km. In multivariate linear regression, as distance from TB diagnostic facilities (b-estimate=−0.25, p<0.001 and altitude (b-estimate=−0.31, p<0.001 increased, the CNRs of TB decreased, whereas a higher population density was associated with increased TB CNRs. Similarly, distance to TB control facilities (b-estimate=−0.27, p<0.001 and altitude (b-estimate=−0.30, p<0.001 were inversely associated with treatment success (proportion of treatment completed or cured cases

  6. A test bed for the future access control system the AD Project

    CERN Document Server

    Scibile, L

    1999-01-01

    This paper describes the design, management and development of the new access control system for the Antiproton Deceleration experimental area, called the AD Project. As this project includes all the elements for the industrial evolution of the present access control system it is an ideal test bed for future access systems. The adoption of new technologies and techniques are described, and the benefits and the shortfalls are highlighted. The open redundant architecture solution, based on a PROFIBUS network and standard industrial components (HP-UNIX, Siemens S7 PLC, Siemens Industrial PC, door locks), guarantees reliability, safety and optimal integration. The project team took advantage of the Goal Directed Project Management technique and managed to define a clear and effective strategy.

  7. A Study on Automated Context-aware Access Control Model Using Ontology

    Science.gov (United States)

    Jang, Bokman; Jang, Hyokyung; Choi, Euiin

    Applications in context-aware computing environment will be connected wireless network and various devices. According to, recklessness access of information resource can make trouble of system. So, access authority management is very important issue both information resource and adapt to system through founding security policy of needed system. But, existing security model is easy of approach to resource through simply user ID and password. This model has a problem that is not concerned about user's environment information. In this paper, propose model of automated context-aware access control using ontology that can more efficiently control about resource through inference and judgment of context information that collect user's information and user's environment context information in order to ontology modeling.

  8. Pace: Privacy-Protection for Access Control Enforcement in P2P Networks

    Science.gov (United States)

    Sánchez-Artigas, Marc; García-López, Pedro

    In open environments such as peer-to-peer (P2P) systems, the decision to collaborate with multiple users — e.g., by granting access to a resource — is hard to achieve in practice due to extreme decentralization and the lack of trusted third parties. The literature contains a plethora of applications in which a scalable solution for distributed access control is crucial. This fact motivates us to propose a protocol to enforce access control, applicable to networks consisting entirely of untrusted nodes. The main feature of our protocol is that it protects both sensitive permissions and sensitive policies, and does not rely on any centralized authority. We analyze the efficiency (computational effort and communication overhead) as well as the security of our protocol.

  9. PRESENTATION OF MANDATORY POLICY OF ACCESS CONTROL VIA THE HARRISONRUSSO-WILLIAM’S MODEL

    Directory of Open Access Journals (Sweden)

    Korolev I. D.

    2015-03-01

    Full Text Available The accepted model of the access control is realized with the monitor of safety in the protected automated information system. Models of safety are considered, as a rule, as a system which is a single whole and has the uniform monitor of safety. Nevertheless, the architecture of the real automated information systems and processes of their functioning can be characterized by distribution. The distributed automated information system consists more than of one local segment representing isolated set of subjects and objects of access. In the distributed system local segments can be realized both on the basis of discretionary, and on the basis of mandatory models of safety (i.e. to be diverse. One of directions of a safety in this case is realization of the general monitor of the safety providing the uniform (coordinated policy of access control. For safe interaction of patchwork systems it’s necessary to bring them to a single model. Hence, while the integration of information systems the problem of their interaction becomes persistent. Thus in the systems processing the information of a various level of confidentiality, it is necessary to realize mandatory access control. In given clause the mandatory policy of the safety presented by classical model of Bell-LaPadula, is described by the elements of classical model of Harrison-Russo-William. Using the mechanisms of change of a matrix access the opportunity of assignment and change of confidentiality marks is described and the observance of safe practices within the limits of mandatory access control is analyzed. The safety of application of the given approach has been proved. The perspective direction of research has been defined

  10. Hysteresis-based congestion control at the B-ISDN access

    Science.gov (United States)

    Wissing, Johannes

    1993-11-01

    Multiplexing of bursty sources and refined congestion control strategies are still the subject of numerous research activities. Broadband applications with very high peak-to-mean bitrate ratio and long silence periods like still picture video gave rise to different ideas of rate control at the B-ISDN network access. Contributions on Input Rate Control for source coded traffic as well as on Server Rate Control within a LAN/ATM Interworking Unit have recently been presented. This paper addresses a congestion avoidance strategy at the network access regarding the aggregated traffic of bursty sources. Depending on the number of active sources as well as on certain defined congestion levels the cell rate at the network access is controlled. The proposed analytical approach is based on the model of uniform and continuous arrival and service. The selected underlying Markov chain contains `split' states in order to handle the congestion correlation. The proposed model is extended to an adaptive Non-Markov system where the buffer filling level is evaluated using a switching hysteresis. This type of congestion measurement turns out to be very useful for an adaptive rate control mechanism that guarantees a certain quality of service while still achieving a good statistical gain. The analytical approach is confirmed by results of a computer simulation that is extended to the more complex case of adaptive rate control.

  11. An Optimal Medium Access Control with Partial Observations for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Servetto Sergio D

    2005-01-01

    Full Text Available We consider medium access control (MAC in multihop sensor networks, where only partial information about the shared medium is available to the transmitter. We model our setting as a queuing problem in which the service rate of a queue is a function of a partially observed Markov chain representing the available bandwidth, and in which the arrivals are controlled based on the partial observations so as to keep the system in a desirable mildly unstable regime. The optimal controller for this problem satisfies a separation property: we first compute a probability measure on the state space of the chain, namely the information state, then use this measure as the new state on which the control decisions are based. We give a formal description of the system considered and of its dynamics, we formalize and solve an optimal control problem, and we show numerical simulations to illustrate with concrete examples properties of the optimal control law. We show how the ergodic behavior of our queuing model is characterized by an invariant measure over all possible information states, and we construct that measure. Our results can be specifically applied for designing efficient and stable algorithms for medium access control in multiple-accessed systems, in particular for sensor networks.

  12. Dominion- An Introductory Concept of Access Control Between Valuable Assets and Mobile Device

    Directory of Open Access Journals (Sweden)

    Neha Dubey

    2013-11-01

    Full Text Available At present methods for providing conditional access to restricted resources and applications for permitting personnel, such as military members, government agencies, or first-responders are not available. The conditional access is provided if the user is an authentic user in one of the authorized geographic location and is connected to specific base transceiver stations or base station controllers. In this work we introduce dominions for mobile security, which are designed to provide this conditional access, are adjustable and congenial with mobile cellular systems, and can run even without being connected to a devoted back-end network. The aim of the architecture is to provide users who satisfy specific pre-conditions access to restricted resources and applications to which they otherwise normally would not be granted access. These mobile security dominions not only provide strict security by authenticating the user and the geographic location of the device, but also prevent access to networks or resources outside of authorized areas and restrict unauthorized users.

  13. Data is key: introducing the data-based access control paradigm

    NARCIS (Netherlands)

    Pieters, Wolter; Tang, Qiang

    2009-01-01

    According to the Jericho forum, the trend in information security is moving the security perimeter as close to the data as possible. In this context, we suggest the idea of data-based access control, where decryption of data is made possible by knowing enough of the data. Trust is thus based on what

  14. Secure access control and large scale robust representation for online multimedia event detection.

    Science.gov (United States)

    Liu, Changyu; Lu, Bin; Li, Huiling

    2014-01-01

    We developed an online multimedia event detection (MED) system. However, there are a secure access control issue and a large scale robust representation issue when we want to integrate traditional event detection algorithms into the online environment. For the first issue, we proposed a tree proxy-based and service-oriented access control (TPSAC) model based on the traditional role based access control model. Verification experiments were conducted on the CloudSim simulation platform, and the results showed that the TPSAC model is suitable for the access control of dynamic online environments. For the second issue, inspired by the object-bank scene descriptor, we proposed a 1000-object-bank (1000OBK) event descriptor. Feature vectors of the 1000OBK were extracted from response pyramids of 1000 generic object detectors which were trained on standard annotated image datasets, such as the ImageNet dataset. A spatial bag of words tiling approach was then adopted to encode these feature vectors for bridging the gap between the objects and events. Furthermore, we performed experiments in the context of event classification on the challenging TRECVID MED 2012 dataset, and the results showed that the robust 1000OBK event descriptor outperforms the state-of-the-art approaches.

  15. Secure Access Control and Large Scale Robust Representation for Online Multimedia Event Detection

    Directory of Open Access Journals (Sweden)

    Changyu Liu

    2014-01-01

    Full Text Available We developed an online multimedia event detection (MED system. However, there are a secure access control issue and a large scale robust representation issue when we want to integrate traditional event detection algorithms into the online environment. For the first issue, we proposed a tree proxy-based and service-oriented access control (TPSAC model based on the traditional role based access control model. Verification experiments were conducted on the CloudSim simulation platform, and the results showed that the TPSAC model is suitable for the access control of dynamic online environments. For the second issue, inspired by the object-bank scene descriptor, we proposed a 1000-object-bank (1000OBK event descriptor. Feature vectors of the 1000OBK were extracted from response pyramids of 1000 generic object detectors which were trained on standard annotated image datasets, such as the ImageNet dataset. A spatial bag of words tiling approach was then adopted to encode these feature vectors for bridging the gap between the objects and events. Furthermore, we performed experiments in the context of event classification on the challenging TRECVID MED 2012 dataset, and the results showed that the robust 1000OBK event descriptor outperforms the state-of-the-art approaches.

  16. Policy Based Access Control in Dynamic Grid-based Collaborative Environment

    NARCIS (Netherlands)

    Y. Demchenko; L. Gommans; A. Tokmakoff; R. van Buuren

    2006-01-01

    This paper describes the design and development of a flexible, customer-driven, security infrastructure for Gridbased Collaborative Environments. The paper proposes further development of the access control model built around a service or resource provisioning agreement (e.g., an experiment or proje

  17. Access and control of agro-biotechnology : Bt cotton, ecological change and risk in China

    NARCIS (Netherlands)

    Ho, Peter; Zhao, Jennifer H.; Xue, Dayuan

    2009-01-01

    This article argues that if the introduction of genetically modified crops (GM crops) in developing countries is to be successful, we can and should not evade questions of access and control of technology. It implies probing into the experiences, perceptions and understanding of GM crops by the prim

  18. Hierarchies in Contextual Role- Based Access Control Model (C-RBAC

    Directory of Open Access Journals (Sweden)

    Muhammad Nabeel Tahir

    2008-11-01

    Full Text Available Hierarchical representation is a natural way of organizing roles in role-based access control systems. Besides its advantages of providing a way of establishing parent-child relationships among different roles, it also provides a facility to design and organize context dependant application roles that users may activate depending on their current context (spatial, temporal conditions. In this paper, we show that if spatial roles are organized in hierarchical relationships, it can cause the problem of disambiguation in making access control decisions especially when the user moves from one location to another location frequently in a single transaction and a single session. We extend our work of Contextual Role-Based Access Control (C-RBAC by introducing hierarchical relationship among subject, location and purpose roles and solve the disambiguation problem in hierarchy by considering user motion direction and his/her context roles (spatial and spatial purpose in order to make more fine grained and better access control decisions.

  19. Functional requirements with survey results for integrated intrusion detection and access control annunciator systems

    Energy Technology Data Exchange (ETDEWEB)

    Arakaki, L.H.; Monaco, F.M.

    1995-09-01

    This report contains the guidance Functional Requirements for an Integrated Intrusion Detection and Access Control Annunciator System, and survey results of selected commercial systems. The survey questions were based upon the functional requirements; therefore, the results reflect which and sometimes how the guidance recommendations were met.

  20. Control of Access to Memory: The Use of Task Interference as a Behavioral Probe

    Science.gov (United States)

    Loft, Shayne; Humphreys, Michael S.; Whitney, Susannah J.

    2008-01-01

    Directed forgetting and prospective memory methods were combined to examine differences in the control of memory access. Between studying two lists of target words, participants were either instructed to forget the first list, or to continue remembering the first list. After study participants performed a lexical decision task with an additional…

  1. Toward an open-access global database for mapping, control, and surveillance of neglected tropical diseases

    DEFF Research Database (Denmark)

    Hürlimann, Eveline; Schur, Nadine; Boutsika, Konstantina;

    2011-01-01

    for monitoring and evaluation. What is currently missing is a georeferenced global database for NTDs providing open-access to the available survey data that is constantly updated and can be utilized by researchers and disease control managers to support other relevant stakeholders. We describe the steps taken...

  2. Socio-economic status influences blood pressure control despite equal access to care

    DEFF Research Database (Denmark)

    Paulsen, M S; Andersen, M; Munck, A P;

    2012-01-01

    OBJECTIVE: Denmark has a health care system with free and equal access to care irrespective of age and socio-economic status (SES). We conducted a cross-sectional study to investigate a possible association between SES and blood pressure (BP) control of hypertensive patients treated in general pr...

  3. 75 FR 47464 - Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control...

    Science.gov (United States)

    2010-08-06

    ... 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 Rule; correction. SUMMARY: The Copyright Office makes a nonsubstantial correction to its regulation announcing...

  4. A Random-Walk Based Privacy-Preserving Access Control for Online Social Networks

    Directory of Open Access Journals (Sweden)

    You-sheng Zhou

    2016-02-01

    Full Text Available Online social networks are popularized with people to connect friends, share resources etc. Meanwhile, the online social networks always suffer the problem of privacy exposure. The existing methods to prevent exposure are to enforce access control provided by the social network providers or social network users. However, those enforcements are impractical since one of essential goal of social network application is to share updates freely and instantly. To better the security and availability in social network applications, a novel random walking based access control of social network is proposed in this paper. Unlike using explicit attribute based match in the existing schemes, the results from random walking are employed to securely compute L1 distance between two social network users in the presented scheme, which not only avoids the leakage of private attributes, but also enables each social network user to define access control policy independently. The experimental results show that the proposed scheme can facilitate the access control for online social network.

  5. FreeBSD Mandatory Access Control Usage for Implementing Enterprise Security Policies

    OpenAIRE

    Bolshakov, Kirill; Reshetova, Elena

    2007-01-01

    FreeBSD was one of the first widely deployed free operating systems to provide mandatory access control. It supports a number of classic MAC models. This tutorial paper addresses exploiting this implementation to enforce typical enterprise security policies of varying complexities.

  6. An Access Control and Trust Management Framework for Loosely-Coupled Multidomain Environments

    Science.gov (United States)

    Zhang, Yue

    2010-01-01

    Multidomain environments where multiple organizations interoperate with each other are becoming a reality as can be seen in emerging Internet-based enterprise applications. Access control to ensure secure interoperation in such an environment is a crucial challenge. A multidomain environment can be categorized as "tightly-coupled" and…

  7. Mining Roles and Access Control for Relational Data under Privacy and Accuracy Constraints

    Science.gov (United States)

    Pervaiz, Zahid

    2013-01-01

    Access control mechanisms protect sensitive information from unauthorized users. However, when sensitive information is shared and a Privacy Protection Mechanism (PPM) is not in place, an authorized insider can still compromise the privacy of a person leading to identity disclosure. A PPM can use suppression and generalization to anonymize and…

  8. Multi-level access control in the data pipeline of the international supply chain system

    NARCIS (Netherlands)

    Pruksasri, P.; Berg, J. van den; Hofman, W.; Daskapan, S.

    2013-01-01

    The Seamless Integrated Data Pipeline system was proposed to the European Union in order to overcome the information quality shortcomings of the current international supply chain information exchange systems. Next to identification and authorization of stakeholders, secure access control needs to b

  9. 77 FR 26789 - Certain Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers and...

    Science.gov (United States)

    2012-05-07

    ... violation of section 337 in the infringement of certain patents. 73 FR 75131. The principal respondent was... order. 75 FR 44989-90 (July 30, 2010). The Commission also issued cease and desist orders against those... COMMISSION Certain Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers...

  10. 30 CFR 816.66 - Use of explosives: Blasting signs, warnings, and access control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Use of explosives: Blasting signs, warnings... STANDARDS-SURFACE MINING ACTIVITIES § 816.66 Use of explosives: Blasting signs, warnings, and access control. (a) Blasting signs. Blasting signs shall meet the specifications of § 816.11. The operator shall—...

  11. 30 CFR 817.66 - Use of explosives: Blasting signs, warnings, and access control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Use of explosives: Blasting signs, warnings... STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.66 Use of explosives: Blasting signs, warnings, and access control. (a) Blasting signs. Blasting signs shall meet the specifications of § 817.11. The operator...

  12. An enhancement of the role-based access control model to facilitate information access management in context of team collaboration and workflow.

    Science.gov (United States)

    Le, Xuan Hung; Doll, Terry; Barbosu, Monica; Luque, Amneris; Wang, Dongwen

    2012-12-01

    Although information access control models have been developed and applied to various applications, few of the previous works have addressed the issue of managing information access in the combined context of team collaboration and workflow. To facilitate this requirement, we have enhanced the Role-Based Access Control (RBAC) model through formulating universal constraints, defining bridging entities and contributing attributes, extending access permissions to include workflow contexts, synthesizing a role-based access delegation model to target on specific objects, and developing domain ontologies as instantiations of the general model to particular applications. We have successfully applied this model to the New York State HIV Clinical Education Initiative (CEI) project to address the specific needs of information management in collaborative processes. An initial evaluation has shown this model achieved a high level of agreement with an existing system when applied to 4576 cases (kappa=0.801). Comparing to a reference standard, the sensitivity and specificity of the enhanced RBAC model were at the level of 97-100%. These results indicate that the enhanced RBAC model can be effectively used for information access management in context of team collaboration and workflow to coordinate clinical education programs. Future research is required to incrementally develop additional types of universal constraints, to further investigate how the workflow context and access delegation can be enriched to support the various needs on information access management in collaborative processes, and to examine the generalizability of the enhanced RBAC model for other applications in clinical education, biomedical research, and patient care.

  13. Access management in Safer Transportation Network Planning : safety principles, planning framework, and library information.

    NARCIS (Netherlands)

    Hummel, T.

    2001-01-01

    This report is one in a series of publications, used in the development of the network planning tool ‘Safer Transportation Network Planning’ (Safer-TNP). The publications were used to guide the development of planning structures, diagnostic tools, planning recommendations, and research information i

  14. Housing and Transport: Access Issues for Disabled International Students in British Universities

    Science.gov (United States)

    Soorenian, Armineh

    2013-01-01

    This article explores two disabled people's "Seven Needs" to independent living, those of "housing" and "transport" issues, in relation to disabled international students in British universities. Firstly, students' living arrangements, including issues related to the suitability of university accommodation…

  15. Modelling Public Transport Route Choice, with Multiple Access and Egress Modes

    NARCIS (Netherlands)

    Brands, T.; De Romph, E.; Veitch, T.; Cook, J.

    2014-01-01

    Public transport (PT) is important, because the current traffic system faces well known problems like congestion, environmental impact and use of public space. To be able to assess the effects of policy measures properly, it is necessary to model the behavior of the (PT) traveler in a realistic way.

  16. Modelling public transport route choice, with multiple access and egress modes

    NARCIS (Netherlands)

    Brands, T.; Romph, de E.; Veitch, T.; Cook, J.

    2014-01-01

    Public transport (PT) is important, because the current traffic system faces well known problems like congestion, environmental impact and use of public space. To be able to assess the effects of policy measures properly, it is necessary to model the behavior of the (PT) traveler in a realistic way.

  17. Management Tools of Cost Controlling at the Gas Transportation Enterprise

    Directory of Open Access Journals (Sweden)

    Vera Vladimirovna Plenkina

    2016-04-01

    Full Text Available The importance of controlling in modern conditions is defined. A brief overview of the main evolutionary stages in the development of the theory and methodology of controlling is provided. The expediency of projection of the concept of controlling on the cost management system at the gas transportation enterprise is justified. The paper points at the grouping of controlling methods in general scientific methods, methods of a number of individual sciences, and specific methods, which are offered to divide into general management methods and methods of cost controlling. The author’s systematization of enterprise-wide management tools of controlling is provided, depending on the most significant areas of activity of the enterprise, management functions, levels of the management hierarchy and the nature of implemented targeted enterprise systems. The cost management methods are structured by management functions and stages of production and sales. The authors point at the predominant classification of each method into strategic and operational tools. The recommendations for further practical use of the presented systematization are provided.

  18. Media access control and resource allocation for next generation passive optical networks

    CERN Document Server

    Ansari, Nirwan

    2013-01-01

    This book focuses on various Passive optical networks (PONs)  types, including currently deployed Ethernet PON (EPON) and Gigabit PON (GPON) as well as next generation WDM PON and OFDM PON. Also this book examines the integrated optical and wireless access networks. Concentrating on two issues in these networks: media access control (MAC) and resource allocation. These two problems can greatly affect performances of PONs such as network resource utilization and QoS of end users. Finally this book will discuss various solutions to address the MAC and resource allocation issues in various PON networks.

  19. Distributed SIR-Aware Opportunistic Access Control for D2D Underlaid Cellular Networks

    OpenAIRE

    Chen, Zheng; Kountouris, Marios

    2014-01-01

    In this paper, we propose a distributed interference and channel-aware opportunistic access control technique for D2D underlaid cellular networks, in which each potential D2D link is active whenever its estimated signal-to-interference ratio (SIR) is above a predetermined threshold so as to maximize the D2D area spectral efficiency. The objective of our SIR-aware opportunistic access scheme is to provide sufficient coverage probability and to increase the aggregate rate of D2D links by harnes...

  20. Access Scheme for Controlling Mobile Agents and its Application to Share Medical Information.

    Science.gov (United States)

    Liao, Yu-Ting; Chen, Tzer-Shyong; Chen, Tzer-Long; Chung, Yu-Fang; Chen, Yu- Xin; Hwang, Jen-Hung; Wang, Huihui; Wei, Wei

    2016-05-01

    This study is showing the advantage of mobile agents to conquer heterogeneous system environments and contribute to a virtual integrated sharing system. Mobile agents will collect medical information from each medical institution as a method to achieve the medical purpose of data sharing. Besides, this research also provides an access control and key management mechanism by adopting Public key cryptography and Lagrange interpolation. The safety analysis of the system is based on a network attacker's perspective. The achievement of this study tries to improve the medical quality, prevent wasting medical resources and make medical resources access to appropriate configuration.

  1. Extending AAA operational model for profile-based access control in ethernet-based Neutral Access Networks

    NARCIS (Netherlands)

    J. Matias; E. Jacob; Y. Demchenko; C. de Laat; L. Gommans

    2010-01-01

    Neutral Access Networks (NAN) have appeared as a new model to overcome some restrictions and lack of flexibility that are present currently in broadband access networks. NAN brings new business opportunities by opening this market to new stakeholders. Although the NAN model is accepted, there are so

  2. Secured Resource Sharing in Cloud Storage using Policy based Access Control

    Directory of Open Access Journals (Sweden)

    S. Imavathy

    2015-11-01

    Full Text Available Cloud computing is a general term anything that involves delivering hosted services, Anything as a Service (AaaS, over the web on demand basis. It uses the web and central remote servers to maintain data and applications. The lack of confidence in trusting information flow(users data are usually processes remotely in unknown machines that do not owned or operated by user in cloud has become common, as users fears of losing control of their own data (like personal, professional, financial, Health. In this approach, a secured cloud storage system that achieves policy-based access control is proposed with an information accountability cloud framework to keep track of the actual usage of the clients data.The access policy generated for the file controls the file accesses and policy revocation makes the file permanently inaccessible. The system is built upon a set of cryptographic key operations that are self- maintained by a set of key managers and adds security features. The access details of the data are logged and auditing also performed.

  3. A Novel Medium Access Control for Ad hoc Networks Based on OFDM System

    Institute of Scientific and Technical Information of China (English)

    YU Yi-fan; YIN Chang-chuan; YUE Guang-xin

    2005-01-01

    Recently, hosts of Medium Access Control (MAC) protocols for Ad hoc radio networks have been proposed to solve the hidden terminal problem and exposed terminal problem. However most of them take into no account the interactions between physical (PHY) system and MAC protocol. Therefore, the current MAC protocols are either inefficient in the networks with mobile nodes and fading channel or difficult in hardware implementation. In this paper, we present a novel media access control for Ad hoc networks that integrates a media access control protocol termed as Dual Busy Tone Multiple Access (DBTMA) into Orthogonal Frequency Division Multiplexing (OFDM) system proposed in IEEE 802.11a standard. The analysis presented in the paper indicates that the proposed MAC scheme achieves performance improvement over IEEE 802.11 protocol about 25%~80% especially in the environment with high mobility and deep fading. The complexity of the proposed scheme is also lower than other implementation of similar busy tone solution. Furthermore, it is compatible with IEEE 802.11a networks.

  4. Optimal Medium Access Control in Cognitive Radios: A Sequential Design Approach

    CERN Document Server

    Lai, Lifeng; Jiang, Hai; Poor, H Vincent

    2008-01-01

    The design of medium access control protocols for a cognitive user wishing to opportunistically exploit frequency bands within parts of the radio spectrum having multiple bands is considered. In the scenario under consideration, the availability probability of each channel is unknown a priori to the cognitive user. Hence efficient medium access strategies must strike a balance between exploring the availability of channels and exploiting the opportunities identified thus far. Using a sequential design approach, an optimal medium access strategy is derived. To avoid the prohibitive computational complexity of this optimal strategy, a low complexity asymptotically optimal strategy is also developed. The proposed strategy does not require any prior statistical knowledge about the traffic pattern on the different channels.

  5. Photonic transport control by spin-optical disordered metasurface

    CERN Document Server

    Veksler, Dekel; Ozeri, Dror; Shitrit, Nir; Kleiner, Vladimir; Hasman, Erez

    2014-01-01

    Photonic metasurfaces are ultrathin electromagnetic wave-molding metamaterials providing the missing link for the integration of nanophotonic chips with nanoelectronic circuits. An extra twist in this field originates from spin-optical metasurfaces providing the photon spin (polarization helicity) as an additional degree of freedom in light-matter interactions at the nanoscale. Here we report on a generic concept to control the photonic transport by disordered (random) metasurfaces with a custom-tailored geometric phase. This approach combines the peculiarity of random patterns to support extraordinary information capacity within the intrinsic limit of speckle noise, and the optical spin control in the geometric phase mechanism, simply implemented in two-dimensional structured matter. By manipulating the local orientations of anisotropic optical nanoantennas, we observe spin-dependent near-field and free-space open channels, generating state-of-the-art multiplexing and interconnects. Spin-optical disordered m...

  6. Environmental control of microtubule-based bidirectional cargo-transport

    CERN Document Server

    Klein, Sarah; Santen, Ludger

    2014-01-01

    Inside cells, various cargos are transported by teams of molecular motors. Intriguingly, the motors involved generally have opposite pulling directions, and the resulting cargo dynamics is a biased stochastic motion. It is an open question how the cell can control this bias. Here we develop a model which takes explicitly into account the elastic coupling of the cargo with each motor. We show that bias can be simply controlled or even reversed in a counterintuitive manner via a change in the external force exerted on the cargo or a variation of the ATP binding rate to motors. Furthermore, the superdiffusive behavior found at short time scales indicates the emergence of motor cooperation induced by cargo-mediated coupling.

  7. 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.

  8. 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.

  9. A METHOD OF AND A SYSTEM FOR CONTROLLING ACCESS TO A SHARED RESOURCE

    DEFF Research Database (Denmark)

    2006-01-01

    A method and a system of controlling access of data items to a shared resource, wherein the data items each is assigned to one of a plurality of priorities, and wherein, when a predetermined number of data items of a priority have been transmitted to the shared resource, that priority will be awa...... will be awaiting, i.e. no further data items are transmitted with that priority, until all lower, non-awaiting priorities have had one or more data items transmitted to the shared resource. In this manner, guarantees services may be obtained for all priorities.......A method and a system of controlling access of data items to a shared resource, wherein the data items each is assigned to one of a plurality of priorities, and wherein, when a predetermined number of data items of a priority have been transmitted to the shared resource, that priority...

  10. A distributed Synchronous reservation multiple access control protocol for mobile Ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yanling; SUN Xianpu; LI Jiandong

    2007-01-01

    This study proposes a new multiple access control protocol named distributed synchronous reservation multiple access control protocol.in which the hidden and exposed terminal problems are solved,and the quality of service(QoS)requirements for real-time traffic are guaranteed.The protocol is founded on time division multiplex address and a different type of traffic is assigned to difierent priority,according to which a node should compete for and reserve the free slots in a different method.Moreover,there is a reservation acknowledgement process before data transmit in each reserved slot,so that the intruded terminal problem is solved.The throughput and average packets drop probability of this protocol are analyzed and simulated in a fully connected network.the results of which indicate that this protocol is efficient enough to support the real-time traffic.and it is more suitable to MANETs.

  11. A MATHEMATICAL MODEL OF ACCESS CONTROL IN BIG DATA USING CONFIDENCE INTERVAL AND DIGITAL SIGNATURE

    Directory of Open Access Journals (Sweden)

    Amine RAHMANI

    2015-11-01

    Full Text Available Nowadays, the concept of big data grows incessantly; recent researches proved that 90% of the whole data existed on the web had been created in last two years. However, this growing bumped by many critical challenges resides generally in security level; the users care about how could providers protect their privacy on their data. Access control, cryptography, and deidentification are the main search areas grouped under a specific domain known as Privacy Preserving Data Publishing. In this paper, we bring in suggestion a new model for access control over big data using digital signature and confidence interval; we first introduce our work by presenting some general concepts used to build our approach then presenting the idea of this report and finally we evaluate our system by conducting several experiments and showing and discussing the results that we got.

  12. 78 FR 41993 - Transport Handling Specialists, Inc.-Continuance in Control Exemption-RSL Railroad, LLC

    Science.gov (United States)

    2013-07-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Surface Transportation Board Transport Handling Specialists, Inc.--Continuance in Control Exemption--RSL Railroad, LLC Transport Handling Specialists, Inc. (THS), has filed a verified notice of exemption...

  13. Quality Test Template toward Multi-user Access Control of Internet-Based System

    Directory of Open Access Journals (Sweden)

    Nan Nie

    2011-06-01

    Full Text Available Aiming at three kinds of Internet-based system quality problems, which is performance, liability and security, the paper proposes a kind of test template during multi-user login and resource access control, which includes test requirement, login script, role-resource correlating and mutation test technique. Some Internet-based systems are tested and diagnosed by automation test technique of test template. At last, system quality can be verified and improved through the realization mechanism of test template.

  14. A MATHEMATICAL MODEL OF ACCESS CONTROL IN BIG DATA USING CONFIDENCE INTERVAL AND DIGITAL SIGNATURE

    OpenAIRE

    Amine RAHMANI; Amine, Abdelmalek; Mohamed Reda HAMOU

    2015-01-01

    Nowadays, the concept of big data grows incessantly; recent researches proved that 90% of the whole data existed on the web had been created in last two years. However, this growing bumped by many critical challenges resides generally in security level; the users care about how could providers protect their privacy on their data. Access control, cryptography, and deidentification are the main search areas grouped under a specific domain known as Privacy Preserving Data Publishi...

  15. Enforcing Access Control in Virtual Organizations Using Hierarchical Attribute-Based Encryption

    OpenAIRE

    Asim, Muhammad; Ignatenko, Tanya; Petkovic, Milan; Trivellato, Daniel; Zannone, Nicola

    2012-01-01

    Virtual organizations are dynamic, inter-organizational collaborations that involve systems and services belonging to different security domains. Several solutions have been proposed to guarantee the enforcement of the access control policies protecting the information exchanged in a distributed system, but none of them addresses the dynamicity characterizing virtual organizations. In this paper we propose a dynamic hierarchical attribute-based encryption (D-HABE) scheme that allows the insti...

  16. A fuzzy expert system to Trust-Based Access Control in crowdsourcing environments

    OpenAIRE

    Olusegun Folorunso; Olusegun Afeez Mustapha

    2015-01-01

    Crowdsourcing has been widely accepted across a broad range of application areas. In crowdsourcing environments, the possibility of performing human computation is characterized with risks due to the openness of their web-based platforms where each crowd worker joins and participates in the process at any time, causing serious effect on the quality of its computation. In this paper, a combination of Trust-Based Access Control (TBAC) strategy and fuzzy-expert systems was used to enhance the qu...

  17. Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

    OpenAIRE

    Abdul Razaque; Elleithy, Khaled M.

    2014-01-01

    This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols,...

  18. A Combined Solution for Routing and Medium Access Control Layer Attacks in Mobile Ad Hoc Networks

    OpenAIRE

    R. Murugan; Shanmugam, A.

    2010-01-01

    Problem statement: In Mobile Ad hoc Network (MANET), both the routing layer and the Medium Access Control (MAC) layer are vulnerable to several attacks. There are very few techniques to detect and isolate the attacks of both these layers simultaneously. In this study, we developed a combined solution for routing and MAC layer attacks. Approach: Our approach, makes use of three techniques simultaneously which consists of a cumulative frequency based detection technique for&...

  19. A human rights view on access to controlled substances for medical purposes under the international drug control framework.

    Science.gov (United States)

    Gispen, Marie Elske C

    2013-11-01

    The world is confronted with a major public health deficit caused by poor access to controlled essential medicines under the international drug control framework. This is affecting millions of patients on a daily basis and resulting in numerous human rights violations. The present review contextualises this deficit from a human rights perspective. Drug control efforts are informed by a twofold objective stemming from the double nature of scheduled substances: free access for medical purposes should be ensured, though non-medical use of substances such as opium should be restricted. The international drug control framework is, in theory, based on this twofold notion, however at the level of interpretation, monitoring, and implementation, a one-sided emphasis is demonstrated. By tracing a parallel between the obligations of states under the international drug control framework and those that derive from human rights law, the review shows that the two systems seem incoherent and conflicting in nature and flags the importance of cross-disciplinary research into drug control and human rights.

  20. 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.

  1. Design of Novel Online Access and Control Interface for Remote Experiment on DC Drives

    Directory of Open Access Journals (Sweden)

    Jagadeesh Chandra A.P

    2009-05-01

    Full Text Available Internet has revolutionized the way in which the information is delivered. Laboratory based courses play an important role in technical education. Automation is changing the nature of these laboratories and the system designer’s focus on Internet accessed experiments owing to the availability of several tools to integrate electronic and mechanical hardware with the World Wide Web. Stand-alone approaches in remote learning have grown tremendously in the recent years. One of the important components in remote experimentation is the integration of Virtual Instruments to perform real hardware tasks in near real-time. The paper describes a web interface to the electrical hardware and integration of LabVIEW Virtual Instruments to the remote access and control of DC Drives. Customized electrical hardware serves as the web interface, supporting various features to remotely control and measure the parameters of the electrical machine. Novel techniques have been used to interface a low power data acquisition system with the DC machine driven by the AC power supply. The system uses the client-server architecture to access the web page of the Virtual Instruments through web browser. The developed system imitates the real control of experiment hardware, but being operated remotely through Internet.

  2. Solvent-driven electron trapping and mass transport in reduced graphites to access perfect graphene

    Science.gov (United States)

    Vecera, Philipp; Holzwarth, Johannes; Edelthalhammer, Konstantin F.; Mundloch, Udo; Peterlik, Herwig; Hauke, Frank; Hirsch, Andreas

    2016-08-01

    Herein, we report on a significant discovery, namely, the quantitative discharging of reduced graphite forms, such as graphite intercalation compounds, graphenide dispersions and graphenides deposited on surfaces with the simple solvent benzonitrile. Because of its comparatively low reduction potential, benzonitrile is reduced during this process to the radical anion, which exhibits a red colour and serves as a reporter molecule for the quantitative determination of negative charges on the carbon sheets. Moreover, this discovery reveals a very fundamental physical-chemical phenomenon, namely a quantitative solvent reduction induced and electrostatically driven mass transport of K+ ions from the graphite intercalation compounds into the liquid. The simple treatment of dispersed graphenides suspended on silica substrates with benzonitrile leads to the clean conversion to graphene. This unprecedented procedure represents a rather mild, scalable and inexpensive method for graphene production surpassing previous wet-chemical approaches.

  3. Control of photon transport properties in nanocomposite nanowires

    Science.gov (United States)

    Moffa, M.; Fasano, V.; Camposeo, A.; Persano, L.; Pisignano, D.

    2016-02-01

    Active nanowires and nanofibers can be realized by the electric-field induced stretching of polymer solutions with sufficient molecular entanglements. The resulting nanomaterials are attracting an increasing attention in view of their application in a wide variety of fields, including optoelectronics, photonics, energy harvesting, nanoelectronics, and microelectromechanical systems. Realizing nanocomposite nanofibers is especially interesting in this respect. In particular, methods suitable for embedding inorganic nanocrystals in electrified jets and then in active fiber systems allow for controlling light-scattering and refractive index properties in the realized fibrous materials. We here report on the design, realization, and morphological and spectroscopic characterization of new species of active, composite nanowires and nanofibers for nanophotonics. We focus on the properties of light-confinement and photon transport along the nanowire longitudinal axis, and on how these depend on nanoparticle incorporation. Optical losses mechanisms and their influence on device design and performances are also presented and discussed.

  4. Control of electronic transport in graphene by electromagnetic dressing.

    Science.gov (United States)

    Kristinsson, K; Kibis, O V; Morina, S; Shelykh, I A

    2016-01-01

    We demonstrated theoretically that the renormalization of the electron energy spectrum near the Dirac point of graphene by a strong high-frequency electromagnetic field (dressing field) drastically depends on polarization of the field. Namely, linear polarization results in an anisotropic gapless energy spectrum, whereas circular polarization leads to an isotropic gapped one. As a consequence, the stationary (dc) electronic transport in graphene strongly depends on parameters of the dressing field: A circularly polarized field monotonically decreases the isotropic conductivity of graphene, whereas a linearly polarized one results in both giant anisotropy of conductivity (which can reach thousands of percents) and the oscillating behavior of the conductivity as a function of the field intensity. Since the predicted phenomena can be observed in a graphene layer irradiated by a monochromatic electromagnetic wave, the elaborated theory opens a substantially new way to control electronic properties of graphene with light. PMID:26838371

  5. Breaking and Fixing Origin-Based Access Control in Hybrid Web/Mobile Application Frameworks.

    Science.gov (United States)

    Georgiev, Martin; Jana, Suman; Shmatikov, Vitaly

    2014-02-01

    Hybrid mobile applications (apps) combine the features of Web applications and "native" mobile apps. Like Web applications, they are implemented in portable, platform-independent languages such as HTML and JavaScript. Like native apps, they have direct access to local device resources-file system, location, camera, contacts, etc. Hybrid apps are typically developed using hybrid application frameworks such as PhoneGap. The purpose of the framework is twofold. First, it provides an embedded Web browser (for example, WebView on Android) that executes the app's Web code. Second, it supplies "bridges" that allow Web code to escape the browser and access local resources on the device. We analyze the software stack created by hybrid frameworks and demonstrate that it does not properly compose the access-control policies governing Web code and local code, respectively. Web code is governed by the same origin policy, whereas local code is governed by the access-control policy of the operating system (for example, user-granted permissions in Android). The bridges added by the framework to the browser have the same local access rights as the entire application, but are not correctly protected by the same origin policy. This opens the door to fracking attacks, which allow foreign-origin Web content included into a hybrid app (e.g., ads confined in iframes) to drill through the layers and directly access device resources. Fracking vulnerabilities are generic: they affect all hybrid frameworks, all embedded Web browsers, all bridge mechanisms, and all platforms on which these frameworks are deployed. We study the prevalence of fracking vulnerabilities in free Android apps based on the PhoneGap framework. Each vulnerability exposes sensitive local resources-the ability to read and write contacts list, local files, etc.-to dozens of potentially malicious Web domains. We also analyze the defenses deployed by hybrid frameworks to prevent resource access by foreign-origin Web content

  6. An enhancement of the role-based access control model to facilitate information access management in context of team collaboration and workflow.

    Science.gov (United States)

    Le, Xuan Hung; Doll, Terry; Barbosu, Monica; Luque, Amneris; Wang, Dongwen

    2012-12-01

    Although information access control models have been developed and applied to various applications, few of the previous works have addressed the issue of managing information access in the combined context of team collaboration and workflow. To facilitate this requirement, we have enhanced the Role-Based Access Control (RBAC) model through formulating universal constraints, defining bridging entities and contributing attributes, extending access permissions to include workflow contexts, synthesizing a role-based access delegation model to target on specific objects, and developing domain ontologies as instantiations of the general model to particular applications. We have successfully applied this model to the New York State HIV Clinical Education Initiative (CEI) project to address the specific needs of information management in collaborative processes. An initial evaluation has shown this model achieved a high level of agreement with an existing system when applied to 4576 cases (kappa=0.801). Comparing to a reference standard, the sensitivity and specificity of the enhanced RBAC model were at the level of 97-100%. These results indicate that the enhanced RBAC model can be effectively used for information access management in context of team collaboration and workflow to coordinate clinical education programs. Future research is required to incrementally develop additional types of universal constraints, to further investigate how the workflow context and access delegation can be enriched to support the various needs on information access management in collaborative processes, and to examine the generalizability of the enhanced RBAC model for other applications in clinical education, biomedical research, and patient care. PMID:22732236

  7. The development of access control system in Fukushima No.2 nuclear power station

    Energy Technology Data Exchange (ETDEWEB)

    Ookubo, S.; Nakai, Y.; Oohira, N.; Kishishita, S. [Tokyo Electric power Co., Tokyo (Japan); Kobayashi, H.; Sano, F. [Fuji Electric Co., Tokyo (Japan); Masuda, M.; Tajima, T.; Oohira, K. [Toshiba Corporation, Tokyo (Japan)

    2002-07-01

    A new radiation work control system has been developed for controlling the entrance and exit of workers from the radiation controlled area in a nuclear power station and has been run in the Fukushima No. 2 Nuclear Power Station of Tokyo Electric Power Co., Inc. since October, 1999. The system is designed to reduce workers burden by simplifying the operation of each equipment that controls access to radiation controlled areas, and to minimize radiation exposure by automatically acquiring dose data during each access and each task. The new system adopted electronic personal dosimeters (gamma radiation EPD) which permit data collection by radio communication, thus improving the conventional alarm-equipped personal dosimeter (EPD) and increasing reliability as primary dosimeters. Furthermore, additional electronic personal dosimeters capable of measuring beta radiation (gamma and beta radiations EPD) were also utilized in specific tasks in October 2001. After a six-month test run of these EPDs, the film badges were discontinued in April 2002 and replaced solely with the EPDs. EPDs are now used as the primary dosimetry for radiation workers.

  8. Using GIS modelling to assess accessibility improvements and its potential indirect effects on the environment due to transport infrastructure plans development

    OpenAIRE

    Ortega Pérez, Emilio; Mancebo Quintana, Santiago; Sánchez Vicente, Alfredo; López Suárez, Elena

    2005-01-01

    The Strategic Environmental Assessment Directive (2001/42/EU) establishes that the Environmental Report must include the identification and evaluation of the likely significant effects on the environment of implementing the Plan or Programme due to be studied. Transport Plans usually generate accessibility improvements or facilitate access between two given points on the territory. One indirect impact that this action implies is a likely pressure increase in those areas where a great improvem...

  9. Toward an open-access global database for mapping, control, and surveillance of neglected tropical diseases.

    Directory of Open Access Journals (Sweden)

    Eveline Hürlimann

    2011-12-01

    Full Text Available BACKGROUND: After many years of general neglect, interest has grown and efforts came under way for the mapping, control, surveillance, and eventual elimination of neglected tropical diseases (NTDs. Disease risk estimates are a key feature to target control interventions, and serve as a benchmark for monitoring and evaluation. What is currently missing is a georeferenced global database for NTDs providing open-access to the available survey data that is constantly updated and can be utilized by researchers and disease control managers to support other relevant stakeholders. We describe the steps taken toward the development of such a database that can be employed for spatial disease risk modeling and control of NTDs. METHODOLOGY: With an emphasis on schistosomiasis in Africa, we systematically searched the literature (peer-reviewed journals and 'grey literature', contacted Ministries of Health and research institutions in schistosomiasis-endemic countries for location-specific prevalence data and survey details (e.g., study population, year of survey and diagnostic techniques. The data were extracted, georeferenced, and stored in a MySQL database with a web interface allowing free database access and data management. PRINCIPAL FINDINGS: At the beginning of 2011, our database contained more than 12,000 georeferenced schistosomiasis survey locations from 35 African countries available under http://www.gntd.org. Currently, the database is expanded to a global repository, including a host of other NTDs, e.g. soil-transmitted helminthiasis and leishmaniasis. CONCLUSIONS: An open-access, spatially explicit NTD database offers unique opportunities for disease risk modeling, targeting control interventions, disease monitoring, and surveillance. Moreover, it allows for detailed geostatistical analyses of disease distribution in space and time. With an initial focus on schistosomiasis in Africa, we demonstrate the proof-of-concept that the establishment

  10. A Network Access Control Framework for 6LoWPAN Networks

    Directory of Open Access Journals (Sweden)

    Amaro F. de Sousa

    2013-01-01

    Full Text Available Low power over wireless personal area networks (LoWPAN, in particular wireless sensor networks, represent an emerging technology with high potential to be employed in critical situations like security surveillance, battlefields, smart-grids, and in e-health applications. The support of security services in LoWPAN is considered a challenge. First, this type of networks is usually deployed in unattended environments, making them vulnerable to security attacks. Second, the constraints inherent to LoWPAN, such as scarce resources and limited battery capacity, impose a careful planning on how and where the security services should be deployed. Besides protecting the network from some well-known threats, it is important that security mechanisms be able to withstand attacks that have not been identified before. One way of reaching this goal is to control, at the network access level, which nodes can be attached to the network and to enforce their security compliance. This paper presents a network access security framework that can be used to control the nodes that have access to the network, based on administrative approval, and to enforce security compliance to the authorized nodes.

  11. An interaction-based access control model (IBAC) for collaborative services

    Energy Technology Data Exchange (ETDEWEB)

    Altunay, Mine; /Fermilab; Byrd, Gregory T.; Brown, Doug E.; Dean, Ralph A.; /North Carolina State U.

    2008-04-01

    A collaboration is a collection of services that work together to achieve a common goal. Although collaborations help when tackling difficult problems, they lead to security issues. First, a collaboration is often performed by services that are drawn from different security domains. Second, a service interacts with multiple peer services during the collaboration. These interactions are not isolated from one another--e.g., data may flow through a sequence of different services. As a result, a service is exposed to multiple peer services in varying degrees, leading to different security threats. We identify the types of interactions that can be present in collaborations, and discuss the security threats due to each type. We propose a model for representing the collaboration context so that a service can be made aware of the existing interactions. We provide an access control model for a service participating in a collaboration. We couple our access control model with a policy model, so that the access requirements from collaborations can be expressed and evaluated.

  12. Can “Feature” be used to Model the Changing Access Control Policies?

    Directory of Open Access Journals (Sweden)

    K.Shantha Kumari

    2012-11-01

    Full Text Available Access control policies [ACPs] regulate the access to data and resources in information systems. These ACPs are framed from the functional requirements and the Organizational security & privacy policies. It was found to be beneficial, when the ACPs are included in the early phases of the software development leading to secure development of information systems. Many approaches are available for including the ACPs in requirements and design phase. They relied on UML artifacts, Aspects and also Feature for this purpose. But the earlier modeling approaches are limited in expressing the evolving ACPs due to organizational policy changes and business process modifications. In this paper, we analyze, whether “Feature”- defined as an increment in program functionality can be used as a modeling entity to represent the Evolving Access control requirements. We discuss the two prominent approaches that use Feature in modeling ACPs. Also we have a comparative analysis to find the suitability of Features in the context of changing ACPs. We conclude with our findings and provide directions for further research.

  13. Design of IP Camera Access Control Protocol by Utilizing Hierarchical Group Key

    Directory of Open Access Journals (Sweden)

    Jungho Kang

    2015-08-01

    Full Text Available Unlike CCTV, security video surveillance devices, which we have generally known about, IP cameras which are connected to a network either with or without wire, provide monitoring services through a built-in web-server. Due to the fact that IP cameras can use a network such as the Internet, multiple IP cameras can be installed at a long distance and each IP camera can utilize the function of a web server individually. Even though IP cameras have this kind of advantage, it has difficulties in access control management and weakness in user certification, too. Particularly, because the market of IP cameras did not begin to be realized a long while ago, systems which are systematized from the perspective of security have not been built up yet. Additionally, it contains severe weaknesses in terms of access authority to the IP camera web server, certification of users, and certification of IP cameras which are newly installed within a network, etc. This research grouped IP cameras hierarchically to manage them systematically, and provided access control and data confidentiality between groups by utilizing group keys. In addition, IP cameras and users are certified by using PKI-based certification, and weak points of security such as confidentiality and integrity, etc., are improved by encrypting passwords. Thus, this research presents specific protocols of the entire process and proved through experiments that this method can be actually applied.

  14. A Group-oriented Access Control Scheme for P2P Networks

    Directory of Open Access Journals (Sweden)

    Wang Xiaoming

    2011-02-01

    Full Text Available A group-oriented access control scheme is proposed for P2P (peer to peer networks. In the proposed scheme, authentication control, admission control and revocation control are used in order to provide security services for P2P networks. Moreover, the proposed scheme can simply and efficient establish share key between two members without interactions, therefore it can perform secure communications with them. The analysis of security and performance shows that the proposed scheme not only can realize authentication and secure communication, but also can easily and efficiently add new group members and revoke malicious group members. Therefore, it is more efficient, and more practical protocol for P2P networks.

  15. A fuzzy expert system to Trust-Based Access Control in crowdsourcing environments

    Directory of Open Access Journals (Sweden)

    Olusegun Folorunso

    2015-07-01

    Full Text Available Crowdsourcing has been widely accepted across a broad range of application areas. In crowdsourcing environments, the possibility of performing human computation is characterized with risks due to the openness of their web-based platforms where each crowd worker joins and participates in the process at any time, causing serious effect on the quality of its computation. In this paper, a combination of Trust-Based Access Control (TBAC strategy and fuzzy-expert systems was used to enhance the quality of human computation in crowdsourcing environment. A TBAC-fuzzy algorithm was developed and implemented using MATLAB 7.6.0 to compute trust value (Tvalue, priority value as evaluated by fuzzy inference system (FIS and finally generate access decision to each crowd-worker. In conclusion, the use of TBAC is feasible in improving quality of human computation in crowdsourcing environments.

  16. AN IDENTITY PRESERVATION SCHEME (IDPS FOR ACCESS CONTROL OF HETEROGENEOUS RESOURCES

    Directory of Open Access Journals (Sweden)

    GULSHAN AHUJA,

    2011-01-01

    Full Text Available The Service Oriented Architecture (SOA is swiftly enabling inter-organizational processes. Web services are the key elements of modern SOA and are composed of self-describing components that can be used by service requestors across the web in a platform independent manner. Dynamic web services environment includes operations between entities from different domains which typically require uthentication and authorization of service requests. However the assumption that all domains may share a global services registry introduces a variety of challenges like how to establish trust relations among unknown service types, controlling and securing access to resources etc. In this paper, authors have proposed an identity preservation scheme (IDPS which will eliminate the need of validating the identity certificates of a service requestor after a level of trust has been established and verified. The proposed scheme will greatly reduce the amount of authorization work required for accessing a across varied domains.

  17. Reduce Threats in Competitive Intelligence System: A Generic Information Fusion Access Control Model

    Directory of Open Access Journals (Sweden)

    Anass El haddadi

    2011-03-01

    Full Text Available Information fusion is a cornerstone of competitive intelligence activity that aims at supporting decisionmaking by collecting, analyzing and disseminating information. This information comes fromheterogeneous data sources. In this paper we present an approach of access control. This approach isfocused both on the information that must be bring to decision-makers and the privacy of individuals whosedata is used to extract this information. This model is based on the standard “Role Based Access Control”(RBAC and is implemented within the entire life cycle of Xplor Every Where (Web service of Tetralogie,it follows methodologies tailored to design privacy-aware systems to be compliant with data protectionregulations.

  18. Design and Analysis of an Attack Resilient and Adaptive Medium access Control Protocol for Computer Networks

    CERN Document Server

    Shukla, Piyush Kumar; Bhadoria, Dr Sarita Singh

    2009-01-01

    The challenge of designing an efficient Medium Access Control (MAC) protocol and analyzing it has been an important research topic for over 30 years. This paper focuses on the performance analysis (through simulation) and modification of a well known MAC protocol CSMA/CD. The existing protocol does not consider the wastage of bandwidth due to unutilized periods of the channel. By considering this fact, performance of MAC protocol can be enhanced. The purpose of this work is to modify the existing protocol by enabling it to adapt according to state of the network. The modified protocol takes appropriate action whenever unutilized periods detected. In this way, to increase the effective bandwidth utilization and determine how it behaves under increasing load, and varying packet sizes. It will also include effects of attacks i.e. Denial of service attacks, Replay Attack, Continuous Channel Access or Exhaustion attack, Flooding attack, Jamming (Radio interference) attack, Selective forwarding attack which degrade...

  19. Centralized Role-Based Access Control for Federated Multi-Domain Environments

    Institute of Scientific and Technical Information of China (English)

    YU Guangcan; LU Zhengding; LI Ruixuan; MUDAR Sarem

    2006-01-01

    The secure interaction among multiple security domains is a major concern. In this paper, we highlight the issues of secure interoperability among multiple security domains operating under the widely accepted Role Based Access Control (RBAC) model. We propose a model called CRBAC that easily establishes a global policy for roles mapping among multiple security domains. Our model is based on an extension of the RBAC model. Also, multiple security domains were composed to one abstract security domain. Also roles in the multiple domains are translated to permissions of roles in the abstract security domain. These permissions keep theirs hierarchies. The roles in the abstract security domain implement roles mapping among the multiple security domains. Then, authorized users of any security domain can transparently access resources in the multiple domains.

  20. 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.

  1. Design of a control system for self-shielded irradiators with remote access capability

    International Nuclear Information System (INIS)

    With self-shielded irradiators like Gamma chambers, and Blood irradiators are being sold by BRIT to customers both within and outside the country, it has become necessary to improve the quality of service without increasing the overheads. The recent advances in the field of communications and information technology can be exploited for improving the quality of service to the customers. A state of the art control system with remote accessibility has been designed for these irradiators enhancing their performance. This will provide an easy access to these units wherever they might be located, through the Internet. With this technology it will now be possible to attend to the needs of the customers, as regards fault rectification, error debugging, system software update, performance testing, data acquisition etc. This will not only reduce the downtime of these irradiators but also reduce the overheads. (author)

  2. Controls on radium transport by adsorption to iron minerals

    Science.gov (United States)

    Chen, M.; Wang, T.; Kocar, B. D.

    2015-12-01

    Radium is a naturally occurring radioactive metal found in many subsurface environments. Radium isotopes are generated by uranium and thorium decay, and are particularly abundant within groundwaters where minimal porewater flux leads to accumulation. These isotopes are used as natural tracers for estimating submarine groundwater discharge (SGD) [1], allowing for large scale estimation of GW fluxes into and out of the ocean [2]. They also represent a substantial hazard in wastewater produced after hydraulic fracturing for natural gas extraction [3], resulting in a significant risk of environmental release to surface and near-surface waters, and increased cost for water treatment or disposal. Adsorption to mineral surfaces represents a dominant pathway of radium retention in subsurface environments. For SGD studies, adsorption processes impact estimates of GW fluxes, while in hydraulic fracturing, radium adsorption to aquifer solids mediates wastewater radium activities. Analysis of past sorption studies revealed large variability in partition coefficients [4], while examination of radium adsorption kinetics and surface complexation have only recently started [5]. Accordingly, we present the results of sorption and column experiments of radium with a suite of iron minerals representative of those found within deep saline and near-surface (freshwater) aquifers, and evaluate impacts of varying salinity solutions through artificial waters. Further, we explore the impacts of pyrite oxidation and ferrihydrite transformation to other iron-bearing secondary minerals on the transport and retention of radium. These results will provide critical information on the mineralogical controls on radium retention in subsurface environments, and will therefore improve predictions of radium groundwater transport in natural and contaminated systems. [1] Charette, M.A., Buesseler, K.O. & Andrews, J.E., Limnol. Oceanogr. (2001). [2] Moore, W.S., Ann. Rev. Mar. Sci. (2010). [3] Vengosh, A

  3. Control system of HLS transport line and Linac focusing power supplies

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The control system of transport line and Linac focusing power supplies of Hefei Light Source was built upon Experimental Physics and Industrial Control System. The hardware construction, software design and performance test of the control system are described.

  4. Federally Qualified Health Centers Minimize the Impact of Loss of Frequency and Independence of Movement in Older Adult Patients through Access to Transportation Services

    OpenAIRE

    Krystal Elaine Knight

    2011-01-01

    Loss of mobility in older adults (65 and older) is associated with falling, loss of independence, and mortality. This paper, which to the author's knowledge is the first of its kind, summarizes findings of Federally Qualified Health Center (FQHC) case reports and how FQHCs minimize the impacts of mobility loss in older adult patients (who would not receive primary services without these transportation programs) by providing access to primary care services through transportation programs. This...

  5. Perti Net-Based Workflow Access Control Model%基于Perti网的工作流访问控制模型研究

    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.

  6. Experimental Investigation on Transmission Control Protocol Throughput Behavior in Optical Fiber Access Networks

    Science.gov (United States)

    Tego, Edion; Matera, Francesco; del Buono, Donato

    2016-03-01

    This article describes an experimental investigation on the behavior of transmission control protocol in throughput measurements to be used in the verification of the service-level agreement between the Internet service provider and user in terms of line capacity for ultra-broadband access networks typical of fiber-to-the-x architectures. It is experimentally shown different conditions in high bandwidth-delay product links where the estimation of the line capacity based on a single transmission control protocol session results are unreliable. Simple equations reported in this work, and experimentally verified, point out the conditions in terms of packet loss, time delay, and line capacity, that allow consideration of the reliability of the measurement carried out with a single transmission control protocol session test by adopting a suitable measurement time duration.

  7. Access control for MPEG video applications using neural network and simulated annealing

    Directory of Open Access Journals (Sweden)

    Ahmed N. U.

    2004-01-01

    Full Text Available We present a dynamic modelfor access control mechanism used in computer communication network applied to MPEG video transmission over Internet. This modelis different fromthosedeveloped inthe previous works related to this topic. In our model, token buckets supported by data buffersare used to shape incoming traffic and one multiplexor, serving all the token pools, multiplexes all theconforming traffic. The model is governed by a system of discrete nonlinear difference equations. Weuse neural network as the feedback controller which receives at its input (measurable available information and provides at its output the optimal control. The simulated annealing algorithm isusedto optimize the system performance by adjusting the weights. For illustration, we presentnumerical results which show that the system performance of MPEG video server can be improved by using neural network and simulated annealing approach.

  8. 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.

  9. A Fuzzy Logic Based Power Control for Wideband Code Division Multiple Access Wireless Networks

    Directory of Open Access Journals (Sweden)

    T. Ravichandran

    2012-01-01

    Full Text Available Problem statement: Resource management is one of the most important engineering issues in 3G systems where multiple traffic classes are supported each being characterized by its required Quality of Service (QoS parameters. Call Admission Control (CAC is one of the resource management functions, which regulates network access to ensure QoS provisioning. Efficient CAC is necessary for the QoS provisioning in WCDMA environment. The effective functioning of WCDMA systems is influenced by the power control utility. Approach: In this study, we propose to design a fuzzy logic based power control for Wideband Code Division Multiple Access Wireless Networks. This proposed technique is aimed at multiple services like voice, video and data for multiclass users. The fuzzy logic technique is used to estimate the optimal admissible users group inclusive of optimum transmitting power level. This technique reduces the interference level and call rejection rate. Results: By simulation results, we demonstrate that the proposed technique achieve reduced energy consumption for a cell with increased throughput. Conclusion: The proposed technique minimizes the power consumption and call rejection rate.

  10. Physical protection of hardware and software. Linking access control systems with operational computer systems

    International Nuclear Information System (INIS)

    The existence and use of software and networks have generated another possibility for perpetrators to influence systems in nuclear facilities or to prepare malevolent acts. Data security has become an element of physical protection plans, not as an end in itself but as a means to achieve physical protection objectives. Physical protection measures are additional measures, which become necessary when other measures that have to be taken (e.g. in compliance with international standards) are insufficient to prevent a hazard to the protection goals through data manipulation by software and hardware. In planning or assessing data protection measures for the purpose of physical protection, it is necessary to differentiate between applications which can, if manipulated, directly endanger the protection goals. The importance of software protection is growing. In particular, because of ageing of components, the existing instrumentation and control systems with their fixed wiring and discrete elements will have to be updated. Computerized access control systems play an eminent role in the physical protection of a nuclear facility. Therefore, most systems are operated as islands. The paper shows that linking of certain systems with other computer systems is possible without inadmissible drawbacks for the physical protection level. It is shown by means of the example of linking together the computer networks of access control, health physics, the flexitime system, the key administration and the operational management system that such linking of systems in nuclear facilities had hidden advantages for all participants

  11. A Model-driven Role-based Access Control for SQL Databases

    Directory of Open Access Journals (Sweden)

    Raimundas Matulevičius

    2015-07-01

    Full Text Available Nowadays security has become an important aspect in information systems engineering. A mainstream method for information system security is Role-based Access Control (RBAC, which restricts system access to authorised users. While the benefits of RBAC are widely acknowledged, the implementation and administration of RBAC policies remains a human intensive activity, typically postponed until the implementation and maintenance phases of system development. This deferred security engineering approach makes it difficult for security requirements to be accurately captured and for the system’s implementation to be kept aligned with these requirements as the system evolves. In this paper we propose a model-driven approach to manage SQL database access under the RBAC paradigm. The starting point of the approach is an RBAC model captured in SecureUML. This model is automatically translated to Oracle Database views and instead-of triggers code, which implements the security constraints. The approach has been fully instrumented as a prototype and its effectiveness has been validated by means of a case study.

  12. Locks and raspberries: a comparative study of single-board computers for access control

    OpenAIRE

    Romin, Andreas

    2016-01-01

    Over the past decade, there has been a drastic development of the single-board computer market. These computers are now in a position where they can compete with classic embedded hardware. Such fast improvement has led ASSA ABLOY, a well-known lock and security company, to see value in replacing some of their existing access control hardware with an off-the-shelf single-board computer. Therefore, a comparative study of single-board computers was performed for this company. Some of the compare...

  13. 角色访问控制%Role based Access Control Model

    Institute of Scientific and Technical Information of China (English)

    毛碧波; 孙玉芳

    2003-01-01

    Role based access control (RBAC)was proposed in 70's, and prevailed in 90's, and then Sandhu etc pro-posed formal RBAC model. Now RBAC is attracting increasing attention, and many governmental and commercial or-ganizations have adopted it, its importance is more and more apparent. In this paper we illuminates the distinctionsand similarities of role and user groups, and based the model that was proposed by Sandhu, we examine the relation-ship of role hierarchies and role constraints and formally describes that, and explain the most important part of roleconstraints ,which is separation of duties.

  14. Authenticated Blind Issuing of Symmetric Keys for Mobile Access Control System without Trusted Parties

    OpenAIRE

    Shin-Yan Chiou

    2013-01-01

    Mobile authentication can be used to verify a mobile user’s identity. Normally this is accomplished through the use of logon passwords, but this can raise the secret-key agreement problem between entities. This issue can be resolved by using a public-key cryptosystem, but mobile devices have limited computation ability and battery capacity and a PKI is needed. In this paper, we propose an efficient, non-PKI, authenticated, and blind issued symmetric key protocol for mobile access control syst...

  15. Design and Implementation of File Access and Control System Based on Dynamic Web

    Institute of Scientific and Technical Information of China (English)

    GAO Fuxiang; YAO Lan; BAO Shengfei; YU Ge

    2006-01-01

    A dynamic Web application, which can help the departments of enterprise to collaborate with each other conveniently, is proposed. Several popular design solutions are introduced at first. Then, dynamic Web system is chosen for developing the file access and control system. Finally, the paper gives the detailed process of the design and implementation of the system, which includes some key problems such as solutions of document management and system security. Additionally, the limitations of the system as well as the suggestions of further improvement are also explained.

  16. GSM-Based Wireless Database Access For Food And Drug Administration And Control

    OpenAIRE

    Engr. Prof Hyacinth C. Inyiama; Engr. Mrs Lois Nwobodo; Engr. Dr. Mrs. Christiana C. Okezie; Engr. Mrs. Nkolika O. Nwazor

    2012-01-01

    GSM (Global system for mobile communication) based wireless database access for food and drug administration and control is a system that enables one to send a query to the database using the short messaging system (SMS) for information about a particular food or drug. It works in such a way that a user needs only send an SMS in order to obtain information about a particular drug produced by a pharmaceutical industry. The system then receives the SMS, interprets it and uses its contents to qu...

  17. Context-Sensitive Access Control Policy Evaluation and Enforcement Using Vulnerability Exploitation Data

    Directory of Open Access Journals (Sweden)

    Hassan Rasheed

    2013-09-01

    Full Text Available Conventional approaches for adapting security enforcement in the face of attacks rely on administrators to make policy changes that will limit damage to the system. Paradigm shifts in the capabilities of attack tools demand supplementary strategies that can also adjust policy enforcement dynamically. We extend the current research by proposing an approach for integrating real-time security assessment data into access control systems. Critical application scenarios are tested to examine the impact of using risk data in policy evaluation and enforcement.

  18. A Flexible Component based Access Control Architecture for OPeNDAP Services

    Science.gov (United States)

    Kershaw, Philip; Ananthakrishnan, Rachana; Cinquini, Luca; Lawrence, Bryan; Pascoe, Stephen; Siebenlist, Frank

    2010-05-01

    Network data access services such as OPeNDAP enable widespread access to data across user communities. However, without ready means to restrict access to data for such services, data providers and data owners are constrained from making their data more widely available. Even with such capability, the range of different security technologies available can make interoperability between services and user client tools a challenge. OPeNDAP is a key data access service in the infrastructure under development to support the CMIP5 (Couple Model Intercomparison Project Phase 5). The work is being carried out as part of an international collaboration including the US Earth System Grid and Curator projects and the EU funded IS-ENES and Metafor projects. This infrastructure will bring together Petabytes of climate model data and associated metadata from over twenty modelling centres around the world in a federation with a core archive mirrored at three data centres. A security system is needed to meet the requirements of organisations responsible for model data including the ability to restrict data access to registered users, keep them up to date with changes to data and services, audit access and protect finite computing resources. Individual organisations have existing tools and services such as OPeNDAP with which users in the climate research community are already familiar. The security system should overlay access control in a way which maintains the usability and ease of access to these services. The BADC (British Atmospheric Data Centre) has been working in collaboration with the Earth System Grid development team and partner organisations to develop the security architecture. OpenID and MyProxy were selected at an early stage in the ESG project to provide single sign-on capability across the federation of participating organisations. Building on the existing OPeNDAP specification an architecture based on pluggable server side components has been developed at the BADC

  19. Controllable spin transport in dual-gated silicene

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu, E-mail: ywang@semi.ac.cn [Department of Physics, Faculty of Science, Kunming University of Science and Technology, Kunming, 650500 Yunnan (China); Lou, Yiyi [Center of Student Community Education and Management, Kunming University of Science and Technology, Kunming, 650500 Yunnan (China)

    2014-07-11

    Based on the dual-gated silicene, we have evaluated theoretically the spin-dependent transport in lateral resonant tunneling structure. By aligning the completely valley-polarized beam with spin-resolved well state in concerned structure, large spin polarization can be expected owing to spin-dependent resonant tunneling mechanism. Under the gate electric field modulation, the forming quantum well state can be externally manipulated, triggering further the emergence of externally-controllable spin polarization. Importantly, integrating the considered structure with a proper valley-filter, which might be constructed from valley-contrasting physics as that in graphene valleytronics, completely-polarized spin beam can also be attained without the assistance of ferromagnetic component, providing thus some profitable strategies to develop nonmagnetic spintronic devices residing on silicene. - Highlights: • Dual-gated silicene forms a lateral spin-resonant tunneling diode. • Resonant spin polarization can be electrically modulated in the concerned spin-RTD. • Dual-gated silicene can be used as beam-dependent spin/valley filter.

  20. Perceptions of transport corridors and intermodal transport - as ways to control the space of freight transport flows

    DEFF Research Database (Denmark)

    Hansen, Leif Gjesing

    2009-01-01

    . In this study stakeholders from Danish and Norwegian ports, ferry operators, train operators, forwarding and road haulage firms has been interviewed in order to analyse how logistical decision-making affect the organisational and physical configuration of intermodal transport solutions in the transport corridor...

  1. F2AC: A Lightweight, Fine-Grained, and Flexible Access Control Scheme for File Storage in Mobile Cloud Computing

    Directory of Open Access Journals (Sweden)

    Wei Ren

    2016-01-01

    Full Text Available Current file storage service models for cloud servers assume that users either belong to single layer with different privileges or cannot authorize privileges iteratively. Thus, the access control is not fine-grained and flexible. Besides, most access control methods at cloud servers mainly rely on computationally intensive cryptographic algorithms and, especially, may not be able to support highly dynamic ad hoc groups with addition and removal of group members. In this paper, we propose a scheme called F2AC, which is a lightweight, fine-grained, and flexible access control scheme for file storage in mobile cloud computing. F2AC can not only achieve iterative authorization, authentication with tailored policies, and access control for dynamically changing accessing groups, but also provide access privilege transition and revocation. A new access control model called directed tree with linked leaf model is proposed for further implementations in data structures and algorithms. The extensive analysis is given for justifying the soundness and completeness of F2AC.

  2. Face Recognition for Access Control Systems Combining Image-Difference Features Based on a Probabilistic Model

    Science.gov (United States)

    Miwa, Shotaro; Kage, Hiroshi; Hirai, Takashi; Sumi, Kazuhiko

    We propose a probabilistic face recognition algorithm for Access Control System(ACS)s. Comparing with existing ACSs using low cost IC-cards, face recognition has advantages in usability and security that it doesn't require people to hold cards over scanners and doesn't accept imposters with authorized cards. Therefore face recognition attracts more interests in security markets than IC-cards. But in security markets where low cost ACSs exist, price competition is important, and there is a limitation on the quality of available cameras and image control. Therefore ACSs using face recognition are required to handle much lower quality images, such as defocused and poor gain-controlled images than high security systems, such as immigration control. To tackle with such image quality problems we developed a face recognition algorithm based on a probabilistic model which combines a variety of image-difference features trained by Real AdaBoost with their prior probability distributions. It enables to evaluate and utilize only reliable features among trained ones during each authentication, and achieve high recognition performance rates. The field evaluation using a pseudo Access Control System installed in our office shows that the proposed system achieves a constant high recognition performance rate independent on face image qualities, that is about four times lower EER (Equal Error Rate) under a variety of image conditions than one without any prior probability distributions. On the other hand using image difference features without any prior probabilities are sensitive to image qualities. We also evaluated PCA, and it has worse, but constant performance rates because of its general optimization on overall data. Comparing with PCA, Real AdaBoost without any prior distribution performs twice better under good image conditions, but degrades to a performance as good as PCA under poor image conditions.

  3. An Effective Massive Sensor Network Data Access Scheme Based on Topology Control for the Internet of Things

    Directory of Open Access Journals (Sweden)

    Meng Yi

    2016-11-01

    Full Text Available This paper considers the distributed access and control problem of massive wireless sensor networks’ data access center for the Internet of Things, which is an extension of wireless sensor networks and an element of its topology structure. In the context of the arrival of massive service access requests at a virtual data center, this paper designs a massive sensing data access and control mechanism to improve the access efficiency of service requests and makes full use of the available resources at the data access center for the Internet of things. Firstly, this paper proposes a synergistically distributed buffer access model, which separates the information of resource and location. Secondly, the paper divides the service access requests into multiple virtual groups based on their characteristics and locations using an optimized self-organizing feature map neural network. Furthermore, this paper designs an optimal scheduling algorithm of group migration based on the combination scheme between the artificial bee colony algorithm and chaos searching theory. Finally, the experimental results demonstrate that this mechanism outperforms the existing schemes in terms of enhancing the accessibility of service requests effectively, reducing network delay, and has higher load balancing capacity and higher resource utility rate.

  4. 48 CFR 247.370 - DD Form 1384, Transportation Control and Movement Document.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false DD Form 1384... Transportation in Supply Contracts 247.370 DD Form 1384, Transportation Control and Movement Document. The transportation office of the shipping activity prepares the DD Form 1384 to accompany all shipments made...

  5. New orientation and accessibility option for persons with visual impairment: transportation applications for remote infrared audible signage.

    Science.gov (United States)

    Crandall, William; Bentzen, Billie Louise; Myers, Linda; Brabyn, John

    2001-05-01

    BACKGROUND: For a blind or visually impaired person, a vital prerequisite to accessing any feature of the built environment is being able to find this feature. Braille signs, even where available, do not replace the functions of print signage because they cannot be read from a distance. Remotely readable infrared signs utilise spoken infrared message transmissions to label key environmental features, so that a blind person with a suitable receiver can locate and identify them from a distance. METHODS: Three problems that are among the most challenging and dangerous faced by blind travellers are negotiating complex transit stations, locating bus stops and safely and efficiently crossing light-controlled intersections. We report the results of human factors studies using a remote infrared audible sign system (RIAS), Talking Signs(R), in these critical tasks, examining issues such as the amount of training needed to use the system, its impact on performance and safety, benefits for different population subgroups and user opinions of its value. RESULTS: Results are presented in the form of both objective performance measures and in subjects' ratings of the usefulness of the system in performing these tasks. Findings are that blind people can quickly and easily learn to use remote infrared audible signage effectively and that its use improves travel safety, efficiency and independence.? CONCLUSIONS: The technology provides equal access to a wide variety of public facilities.

  6. Design and analysis of a biometric access control system using an electronic olfactory device to identify human odour characteristics

    OpenAIRE

    McMillan, Stephen

    2000-01-01

    The use of an electronic olfactory device, termed an electronic 'nose', was investigated for the detection of unique human odour characteristics. The detection of these unique odours was applied to the field of biometrics for access control, where a human's unique characteristics were used to authenticate a user of an access control system. An electronic odour sensing device was designed and constructed using an array of conducting polymer gas sensors in order to facilitate the regular screen...

  7. Improved efficiency access control equipment and explosive, weapons and drug abuse detection

    International Nuclear Information System (INIS)

    The second generation portal explosives detector has been designed with increased detection capability and convenience in service. The method of detection and performance relative to the first generation is described. A novel method of auto-calibration and self diagnosis is described and results are discussed. Improvements in convenience of operation have been achieved and operating space and costs reduced by combining metal detection capability, together with explosives detection. This allows both alarm signal and diagnostic outputs to be combined on a single remote panel in the guard room, and reduces the number of guards needed to man the access control. This type of access control is entirely a defensive measure against attack but a further additional feature is proposed which will also check the state of mind of all personnel passing through the check point. Any person suffering from the effect of narcotic or alcohol will be detected by their inability to reproduce their normal signature. A new method of signature analysis in five dimensions is described together with proposals for integrating the check without increasing the time in the test area. Some recent results on the effects of alcohol on signature reproduction is given

  8. 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.

  9. OBLIVIOUS TRANSFER WITH ACCESS CONTROL AND IDENTITYBASED ENCRYPTION WITH ANONYMOUS KEY ISSUING

    Institute of Scientific and Technical Information of China (English)

    Xu Lingling; Zhang Fangguo; Wen Yamin

    2011-01-01

    In ACM'CCS 2009,Camenisch,et al.proposed the Obhvious Transfer with Access Control (AC-OT) in which each item is associated with an attribute set and can only be available,on request,to the users who have all the attributes in the associated set.Namely,AC-OT achieves access control policy for conjunction of attributes.Essentially,the functionality of AC-OT is equivalent to the simplified version that we call AC-OT-SV:for each item,one attribute is associated with it,and it is requested that only the users who possess the associated attribute can obtain the item by queries.On one hand,AC-OT-SV is a special case of AC-OT when there is just one associated attribute with each item.On the other hand,any AC-OT can be realized by an AC-OT-SV.In this paper,we first present a concrete AC-OT-SV protocol which is proved to be secure in the model defined by Camenisch,et al..Then from the protocol,interestingly,a concrete Identity-Based Encryption (IBE) with Anonymous Key Issuing (AKI) is given which is just a direct application to AC-OT-SV.By comparison,we show that the AKI protocol we present is more efficient in communications than that proposed by Chow.

  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. CONTEXT BASED ANDROID APPLICATIONADMINISTRATIVE ACCESS CONTROL (CBAA–AAC FOR SMART PHONES

    Directory of Open Access Journals (Sweden)

    S. Sharavanan

    2016-07-01

    Full Text Available Android applications in smart phones are generally towards provide greater flexibility and convince for users. Considering the fact that the Android applications are having privilege to access data and resources in mobile after it gets installed (one time permission provided by end user on the time installation, these application may also lead to issues in security for the user data as well as issues relate smart phone with peripheral environment. A practical example for an issue which relates smart phone with peripheral environment can be even an Android smart phone application of a college student use camera resource to capture photos of R&D cell and transfer without user or organization permission. The security of the organization and user should be prevented by providing an adoptable solution. The proposed concept of CBAA-AAC (Context Based Android Application Administrative Access Control is used to control the privileges of any Android application over a corresponding longitude and latitude by the organization administrator. In this way, administrator is able to block malicious application of every individual smart phone which can have activity towards utilizing services and resources that may affect the security of the organization, such an move is must for assuring security of any organization and educational institutions while they allow users to “bring their own smart phones/mobile devices” into the campus.

  12. On the Design of Energy Efficient Optical Networks with Software Defined Networking Control Across Core and Access Networks

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Yan, Ying; Dittmann, Lars

    2013-01-01

    This paper presents a Software Defined Networking (SDN) control plane based on an overlay GMPLS control model. The SDN control platform manages optical core networks (WDM/DWDM networks) and the associated access networks (GPON networks), which makes it possible to gather global information...

  13. Simulation-Based Planning and Control of Transport Flows in Port Logistic Systems

    OpenAIRE

    Antonio Diogo Passos Lima; Frederico Werner de Mascarenhas; Enzo Morosini Frazzon

    2015-01-01

    In highly dynamic and uncertain transport conditions, transport transit time has to be continuously monitored so that the service level is ensured at a proper cost. The aim of this research is to propose and to test a procedure which allows an agile planning and control of transport flows in port logistic systems. The procedure couples an agent-based simulation and a queueing theory model. In this paper, the transport scheduling performed by an agent at the intermodal terminal was taken into ...

  14. Infection control in hemodialysis units: A quick access to essential elements

    Directory of Open Access Journals (Sweden)

    Ayman Karkar

    2014-01-01

    Full Text Available Infection is the most common cause of hospitalization and the second most common cause of mortality among hemodialysis (HD patients, after cardiovascular disease. HD patients as well as the dialysis staff are vulnerable to contracting health-care-associated infections (HAIs due to frequent and prolonged exposure to many possible contaminants in the dialysis environment. The extracorporeal nature of the therapy, the associated common environmental conditions and the immune compromised status of HD patients are major predisposing factors. The evident increased potential for transmission of infections in the HD settings led to the creation and implementation of specific and stricter infection prevention and control measures in addition to the usual standard precautions. Different international organizations have generated guidelines and recommendations on infection prevention and control for implementation in the HD settings. These include the Centers for Disease Control and Prevention (CDC, the Association of Professionals in Infection Control (APIC, the Kidney Disease Outcomes Quality Initiative (K/DOQI, the European Best Practice Guidelines/European Renal Best Practice (EBPG/ERBP and the Kidney Disease: Improving Global Outcomes (KDIGO. However, these guidelines are extensive and sometimes vary among different guideline-producing bodies. Our aim in this review is to facilitate the access, increase the awareness and encourage implementation among dialysis providers by reviewing, extracting and comparing the essential elements of guidelines and recommendations on infection prevention and control in HD units.

  15. Bank Access Control of Electronic Payment Based on SPKI%基于SPKI电子支付中的银行端访问控制

    Institute of Scientific and Technical Information of China (English)

    王茜; 王富强; 傅鹤岗; 朱庆生

    2003-01-01

    In the system of electronic payment based on SPKI, access control of bank acts as the important function of identification, protecting customer's privacy and ensuring payment. The paper proposes the model of bank access control, and describes the frame and the steps of the access control. Finally, the paper analyzes the characteristics of the model.

  16. PANATIKI: a network access control implementation based on PANA for IoT devices.

    Science.gov (United States)

    Moreno Sanchez, Pedro; Marin Lopez, Rafa; Gomez Skarmeta, Antonio F

    2013-01-01

    Internet of Things (IoT) networks are the pillar of recent novel scenarios, such as smart cities or e-healthcare applications. Among other challenges, these networks cover the deployment and interaction of small devices with constrained capabilities and Internet protocol (IP)-based networking connectivity. These constrained devices usually require connection to the Internet to exchange information (e.g., management or sensing data) or access network services. However, only authenticated and authorized devices can, in general, establish this connection. The so-called authentication, authorization and accounting (AAA) services are in charge of performing these tasks on the Internet. Thus, it is necessary to deploy protocols that allow constrained devices to verify their credentials against AAA infrastructures. The Protocol for Carrying Authentication for Network Access (PANA) has been standardized by the Internet engineering task force (IETF) to carry the Extensible Authentication Protocol (EAP), which provides flexible authentication upon the presence of AAA. To the best of our knowledge, this paper is the first deep study of the feasibility of EAP/PANA for network access control in constrained devices. We provide light-weight versions and implementations of these protocols to fit them into constrained devices. These versions have been designed to reduce the impact in standard specifications. The goal of this work is two-fold: (1) to demonstrate the feasibility of EAP/PANA in IoT devices; (2) to provide the scientific community with the first light-weight interoperable implementation of EAP/PANA for constrained devices in the Contiki operating system (Contiki OS), called PANATIKI. The paper also shows a testbed, simulations and experimental results obtained from real and simulated constrained devices. PMID:24189332

  17. PANATIKI: a network access control implementation based on PANA for IoT devices.

    Science.gov (United States)

    Moreno Sanchez, Pedro; Marin Lopez, Rafa; Gomez Skarmeta, Antonio F

    2013-11-01

    Internet of Things (IoT) networks are the pillar of recent novel scenarios, such as smart cities or e-healthcare applications. Among other challenges, these networks cover the deployment and interaction of small devices with constrained capabilities and Internet protocol (IP)-based networking connectivity. These constrained devices usually require connection to the Internet to exchange information (e.g., management or sensing data) or access network services. However, only authenticated and authorized devices can, in general, establish this connection. The so-called authentication, authorization and accounting (AAA) services are in charge of performing these tasks on the Internet. Thus, it is necessary to deploy protocols that allow constrained devices to verify their credentials against AAA infrastructures. The Protocol for Carrying Authentication for Network Access (PANA) has been standardized by the Internet engineering task force (IETF) to carry the Extensible Authentication Protocol (EAP), which provides flexible authentication upon the presence of AAA. To the best of our knowledge, this paper is the first deep study of the feasibility of EAP/PANA for network access control in constrained devices. We provide light-weight versions and implementations of these protocols to fit them into constrained devices. These versions have been designed to reduce the impact in standard specifications. The goal of this work is two-fold: (1) to demonstrate the feasibility of EAP/PANA in IoT devices; (2) to provide the scientific community with the first light-weight interoperable implementation of EAP/PANA for constrained devices in the Contiki operating system (Contiki OS), called PANATIKI. The paper also shows a testbed, simulations and experimental results obtained from real and simulated constrained devices.

  18. Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Abdul Razaque

    2014-03-01

    Full Text Available This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC for wireless sensor networks (WSNs, which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN, which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS, which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS, which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

  19. Access Denied

    Science.gov (United States)

    Villano, Matt

    2008-01-01

    Building access control (BAC)--a catchall phrase to describe the systems that control access to facilities across campus--has traditionally been handled with remarkably low-tech solutions: (1) manual locks; (2) electronic locks; and (3) ID cards with magnetic strips. Recent improvements have included smart cards and keyless solutions that make use…

  20. GABA transporters control GABAergic neurotransmission in the mouse subplate.

    Science.gov (United States)

    Unichenko, P; Kirischuk, S; Luhmann, H J

    2015-09-24

    The subplate is a transient layer between the cortical plate and intermediate zone in the developing cortex. Thalamo-cortical axons form temporary synapses on subplate neurons (SPns) before invading the cortical plate. Neuronal activity within the subplate is of critical importance for the development of neocortical circuits and architecture. Although both glutamatergic and GABAergic inputs on SPns were reported, short-term plasticity of GABAergic transmission has not been investigated yet. GABAergic postsynaptic currents (GPSCs) were recorded from SPns in coronal neocortical slices prepared from postnatal day 3-4 mice using whole-cell patch-clamp technique. Evoked GPSCs (eGPSCs) elicited by electrical paired-pulse stimulation demonstrated paired-pulse depression at all interstimulus intervals tested. Baclofen, a specific GABAB receptor (GABABR) agonist, reduced eGPSC amplitudes and increased paired-pulse ratio (PPR), suggesting presynaptic location of functional GABABRs. Baclofen-induced effects were alleviated by (2S)-3-[[(1S)-1-(3,4-dichlorophenyl)ethyl]amino-2-hydroxypropyl](phenylmethyl)phosphinic acid (CGP55845), a selective GABABR blocker. Moreover, CGP55845 increased eGPSC amplitudes and decreased PPR even under control conditions, indicating that GABABRs are tonically activated by ambient GABA. Because extracellular GABA concentration is mainly regulated by GABA transporters (GATs), we asked whether GATs release GABA. 1,2,5,6-tetrahydro-1-[2-[[(diphenylmethylene)amino]oxy]ethyl]-3-pyridinecarboxylic acid (NNC-711) (10μM), a selective GAT-1 blocker, increased eGPSC decay time, decreased eGPSC amplitudes and PPR. The two last effects but not the first one were blocked by CGP55845, indicating that GAT-1 blockade causes an elevation of extracellular GABA concentration and in turn activation of extrasynaptic GABAARs and presynaptic GABABRs. 1-[2-[tris(4-methoxyphenyl)methoxy]ethyl]-(S)-3-piperidinecarboxylic acid (SNAP-5114), a specific GAT-2/3 blocker, failed

  1. Measuring and controlling the transport of magnetic nanoparticles

    Science.gov (United States)

    Stephens, Jason R.

    increases with pore diameter. We find that fluxes are faster in aqueous solutions than in hexane, which is attributed to the hydrophilic nature of the porous membranes and differences in wettability. The impact of an applied magnetic flux gradient, which induces magnetization and motion, on permeation is also examined. Surface chemistry plays an important role in determining flux through porous media such as in the environment. Diffusive flux of nanoparticles through alkylsilane modified porous alumina is measured as a model for understanding transport in porous media of differing surface chemistries. Experiments are performed as a function of particle size, pore diameter, attached hydrocarbon chain length and chain terminus, and solvent. Particle fluxes are monitored by the change in absorbance of the solution in the receiving side of a diffusion cell. In general, flux increases when the membranes are modified with alkylsilanes compared to untreated membranes, which is attributed to the hydrophobic nature of the porous membranes and differences in wettability. We find that flux decreases, in both hexane and aqueous solutions, when the hydrocarbon chain lining the interior pore wall increases in length. The rate and selectivity of transport across these membranes is related to the partition coefficient (Kp) and the diffusion coefficient (D) of the permeating species. By conducting experiments as a function of initial particle concentration, we find that KpD increases with increasing particle size, is greater in alkylsilane--modified pores, and larger in hexane solution than water. The impact of the alkylsilane terminus (--CH3, --Br, --NH2, --COOH) on permeation in water is also examined. In water, the highest KpD is observed when the membranes are modified with carboxylic acid terminated silanes and lowest with amine terminated silanes as a result of electrostatic effects during translocation. Finally, the manipulation of magnetic nanoparticles for the controlled formation

  2. Access Control in IoT/M2M - Cloud Platform

    DEFF Research Database (Denmark)

    Anggorojati, Bayu

    Billions of devices are connected to the Internet nowadays, and the number will continue to grow in the future thanks to the advances in the electronics and telecommunication technology developments. Its application in broad aspects of human’s life brings a lot of benefits by improving productivity...... and quality of life. This paradigm, which is often called Internet of Things (IoT) or Machine-to-Machine (M2M), will provide an unprecedented opportunity to create applications and services that go far beyond the mere purpose of each participant. Many studies on the both technical and social aspects of Io......T have shown that the concern about the security and privacy play a huge role for the mass adoption of the IoT/M2M as cloud services. Among the important topics within the security and privacy, the access control is an important mechanism, which essentially manages how the important assets or resource...

  3. RFID card based access control system with counter for Indus Complex

    International Nuclear Information System (INIS)

    As per norms of the Atomic energy regulatory board (AERB) to operate a facility in round the clock which has a potential of radiation exposure, radiation safety rules are to be followed. Indus -1 and Indus-2 are synchrotron radiation sources which are open for various users round the clock. To monitor the persons inside the defined zone at any given time, a system is setup consisting of RF ID cards and their readers along with dedicated software. Software is developed in Visual Basic and uses UDP network protocol for receiving data from readers installed at various locations and connected to local area network. The paper describes the access control scheme followed in Indus Accelerator Complex. (author)

  4. [Assessment of exposure to cancerogenic aromatic hydrocarbon during controlled-access highways management activities].

    Science.gov (United States)

    Martinotti, I; Cirla, A M; Cottica, D; Cirla, P E

    2011-01-01

    The purpose of this study was an integrated assessment of exposure to benzene and Polycyclic Aromatic Hydrocarbons (PAH) in 29 workers employed to manage a controlled-access highways. A campaign was performed in summertime by environmental monitoring (active and passive airborne personal sampler), as well as by biological monitoring (urine samples of the beginning and of the end of daily shift, baseline after two days of vacation). The measured environmental levels did not differ from background environmental concentrations found in a metropolitan area (i.e. benzo[a]pyrene < 1 ng/m3; benzene < 5 mcg/m3), and the results of biological monitoring were in agreement and were compatible with extra-professional habits of the investigated subjects (1-hydroxipyrene 50-990 ng/g creatinine; unmetabolized benzene 15-2010 ng/I; t-t muconic acid < 4-222 mcg/g creatinine).

  5. Modified Distributed Medium Access Control Algorithm Based on Multi-Packets Reception in Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    ZHENG Qing; YANG Zhen

    2005-01-01

    Based on the Multi-Packet Reception(MPR)capability at the physical layer and the Distributed Coordination Function(DCF)of the IEEE 802.11 MAC protocol,we propose a modified new solution about WAITING mechanism to make full use of the MPR capability in this paper,which is named as modified distributed medium access control algorithm.We describe the details of each step of the algorithm after introducing the WAITING mechanism.Then,we also analyze how the waiting-time affects the throughput performance of the network.The network simulator NS-2 is used to evaluate the throughput performance of the new WAITING algorithm and we compare it with IEEE 802.11 MAC protocol and the old WAITING algorithm.The experimental results show that our new algorithm has the best performance.

  6. An Approach to Enforcing Clark-Wilson Model in Role-based Access Control Model

    Institute of Scientific and Technical Information of China (English)

    LIANGBin; SHIWenchang; SUNYufang; SUNBo

    2004-01-01

    Using one security model to enforce another is a prospective solution to multi-policy support. In this paper, an approach to the enforcing Clark-Wilson data integrity model in the Role-based access control (RBAC) model is proposed. An enforcement construction with great feasibility is presented. In this construction, a direct way to enforce the Clark-Wilson model is provided, the corresponding relations among users, transformation procedures, and constrained data items are strengthened; the concepts of task and subtask are introduced to enhance the support to least-privilege. The proposed approach widens the applicability of RBAC. The theoretical foundation for adopting Clark-Wilson model in a RBAC system with small cost is offered to meet the requirements of multi-policy support and policy flexibility.

  7. Study on Mandatory Access Control in a Secure Database Management System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper proposes a security policy model for mandatory access control in class B1 database management system whose level of labeling is tuple. The relation-hierarchical data model is extended to multilevel relation-hierarchical data model. Based on the multilevel relation-hierarchical data model, the concept of upper-lower layer relational integrity is presented after we analyze and eliminate the covert channels caused by the database integrity. Two SQL statements are extended to process polyinstantiation in the multilevel secure environment. The system is based on the multilevel relation-hierarchical data model and is capable of integratively storing and manipulating multilevel complicated objects (e. g., multilevel spatial data) and multilevel conventional data ( e. g., integer. real number and character string).

  8. Near-Optimal Deviation-Proof Medium Access Control Designs in Wireless Networks

    CERN Document Server

    Phan, Khoa Tran; van der Schaar, Mihaela

    2010-01-01

    Distributed medium access control (MAC) protocols are essential for the proliferation of low cost, decentralized wireless local area networks (WLANs). Most MAC protocols are designed with the presumption that nodes comply with prescribed rules. However, selfish nodes have natural motives to manipulate protocols in order to improve their own performance. This often degrades the performance of other nodes as well as that of the overall system. In this work, we propose a class of protocols that limit the performance gain which nodes can obtain through selfish manipulation while incurring only a small efficiency loss. The proposed protocols are based on the idea of a review strategy, with which nodes collect signals about the actions of other nodes over a period of time, use a statistical test to infer whether or not other nodes are following the prescribed protocol, and trigger a punishment if a departure from the protocol is perceived. We consider the cases of private and public signals and provide analytical a...

  9. 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.

  10. A Time Tree Medium Access Control for Energy Efficiency and Collision Avoidance in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Kilhung Lee

    2010-03-01

    Full Text Available This paper presents a medium access control and scheduling scheme for wireless sensor networks. It uses time trees for sending data from the sensor node to the base station. For an energy efficient operation of the sensor networks in a distributed manner, time trees are built in order to reduce the collision probability and to minimize the total energy required to send data to the base station. A time tree is a data gathering tree where the base station is the root and each sensor node is either a relaying or a leaf node of the tree. Each tree operates in a different time schedule with possibly different activation rates. Through the simulation, the proposed scheme that uses time trees shows better characteristics toward burst traffic than the previous energy and data arrival rate scheme.

  11. MobileCoDaC – A transportable control, data acquisition and communication infrastructure for Wendelstein 7-X

    International Nuclear Information System (INIS)

    Highlights: • MobileCoDaC is a transportable CoDaC infrastructure for Wendelstein 7-X. • It allows in situ testing and commissioning of components to be used at W7-X by providing W7-X CoDaC infrastructure. • It has been used successfully for test and commissioning of the HEXOS diagnostic at Forschungszentrum Jülich. - Abstract: MobileCoDaC is a test bed allowing in situ testing and commissioning the control and data acquisition of components to be operated at Wendelstein 7-X. It is a minimized replica of the functionality of the complete W7-X CoDaC infrastructure and can be operated independently. MobileCoDaC contains a set of W7-X CoDaC servers, network infrastructure, and accessories for remote access. All hardware is mounted in a single transportable rack system. Moreover, it provides the software infrastructure and user applications for experiment preparation, experiment operation, trouble shooting and experiment data access. MobileCoDaC has been operated successfully for test and commissioning of the control and data acquisition of the HEXOS (high efficiency extreme ultraviolet overview spectrometer) diagnostic at Forschungszentrum Jülich

  12. 基于XACML的EPCIS访问控制模型%Access Control Model for EPCIS Based on XACML

    Institute of Scientific and Technical Information of China (English)

    李景峰; 李云鹏

    2013-01-01

    根据供应链系统对EPC信息服务(EPCIS)提出的访问控制需求,设计一种基于可扩展访问控制标记语言(XACML)的EPCIS访问控制模型.模型中的访问控制执行接口利用方法拦截技术实现对访问请求的拦截,并生成决策上下文对象.访问控制服务组件基于决策上下文对象中包含的用户、资源、环境和动作属性实现对访问请求的动态评估.安全通信组件利用安全性断言标记语言,结合缓存机制实现XACML授权请求/响应的实时传输.访问控制流程表明,该模型能够实现灵活的访问控制策略部署和管理,具有供应链产品信息访问控制的动态性、异构性等特点.%The special access control requirements of EPC Information Service(EPCIS) in the supply chains are analyzed,and an EPCIS access control model based on Extensible Access Control Markup Language(XACML) is presented.The access control execution interface in the model can intercept the access requests by using the method intercepting technology,and produce the corresponding judgment context.Based on the user property,resource property,environment property and action property,which are included into the judgment context,the access control service component can dynamically assess the access requests.The secure communication component can effectively provide the real-time transmission for XACML authorization request/response messages,by combining the Security Assertion Markup Language(SAML) and the caching mechanism.The access control workflow indicates that the model can implement the flexible and variable deployment and management of the access control strategies,which is well fit for implement highly dynamic and heterogeneous access control function for the product information in the supply chains.

  13. Ion Transport through Diffusion Layer Controlled by Charge Mosaic Membrane

    Directory of Open Access Journals (Sweden)

    Akira Yamauchi

    2012-01-01

    Full Text Available The kinetic transport behaviors in near interface of the membranes were studied using commercial anion and cation exchange membrane and charge mosaic membrane. Current-voltage curve gave the limiting current density that indicates the ceiling of conventional flux. From chronopotentiometry above the limiting current density, the transition time was estimated. The thickness of boundary layer was derived with conjunction with the conventional limiting current density and the transition time from steady state flux. On the other hand, the charge mosaic membrane was introduced in order to examine the ion transport on the membrane surface in detail. The concentration profile was discussed by the kinetic transport number with regard to the water dissociation (splitting on the membrane surface.

  14. Cloud and the City: Facilitating Flexible Access Control over Data Streams

    CERN Document Server

    Wang, Wen Qiang; Lim, Hock Beng; Datta, Anwitaman

    2012-01-01

    The proliferation of sensing devices create plethora of data-streams, which in turn can be harnessed to carry out sophisticated analytics to support various real-time applications and services as well as long-term planning, e.g., in the context of intelligent cities or smart homes to name a few prominent ones. A mature cloud infrastructure brings such a vision closer to reality than ever before. However, we believe that the ability for data-owners to flexibly and easily to control the granularity at which they share their data with other entities is very important - in making data owners feel comfortable to share to start with, and also to leverage on such fine-grained control to realize different business models or logics. In this paper, we explore some basic operations to flexibly control the access on a data stream and propose a framework eXACML+ that extends OASIS's XACML model to achieve the same. We develop a prototype using the commercial StreamBase engine to demonstrate a seamless combination of strea...

  15. Coordinated Scheduling and Power Control in Cloud-Radio Access Networks

    KAUST Repository

    Douik, Ahmed

    2015-12-01

    This paper addresses the joint coordinated scheduling and power control problem in cloud-enabled networks. Consider the downlink of a cloud-radio access network (CRAN), where the cloud is only responsible for the scheduling policy, power control, and synchronization of the transmit frames across the single-antenna base-stations (BS). The transmit frame consists of several time/frequency blocks, called power-zones (PZ). The paper considers the problem of scheduling users to PZs and determining their power levels (PL), by maximizing the weighted sum-rate under the practical constraints that each user cannot be served by more than one base-station, but can be served by one or more power-zones within each base-station frame. The paper solves the problem using a graph theoretical approach by introducing the joint scheduling and power control graph formed by several clusters, where each is formed by a set of vertices, representing the possible association of users, BSs, and PLs for one specific PZ. The problem is, then, formulated as a maximumweight clique problem, in which the weight of each vertex is the sum of the benefits of the individual associations belonging to that vertex. Simulation results suggest that the proposed crosslayer scheme provides appreciable performance improvement as compared to schemes from recent literature.

  16. Integrated transportation and energy sector CO2 emission control strategies

    DEFF Research Database (Denmark)

    Lund, Henrik; Münster, Ebbe

    2006-01-01

    is the use of biofuel (ethanol) and synthetic fuel (methanol) for internal combustion cars. An increase in the fraction of electricity delivered by fluctuating sources like wind power will lead to excess electricity production and the two aforementioned scenarios have a substantial effect on the decrease...... and power production (CHP), while the transport sector can assist the energy system in integrating a higher degree of intermittent energy and CHP. Two scenarios for partial conversion of the transport fleet have been considered. One is battery cars combined with hydrogen fuel cell cars, while the other...

  17. Automated Analysis of Scenario-based Specifications of Distributed Access Control Policies with Non-Mechanizable Activities (Extended Version)

    OpenAIRE

    Barletta, Michele; Ranise, Silvio; Viganò, Luca

    2012-01-01

    The advance of web services technologies promises to have far-reaching effects on the Internet and enterprise networks allowing for greater accessibility of data. The security challenges presented by the web services approach are formidable. In particular, access control solutions should be revised to address new challenges, such as the need of using certificates for the identification of users and their attributes, human intervention in the creation or selection of the certificates, and (cha...

  18. Algorithm and data support of traffic congestion forecasting in the controlled transport

    Science.gov (United States)

    Dmitriev, S. V.

    2015-06-01

    The topicality of problem of the traffic congestion forecasting in the logistic systems of product movement highways is considered. The concepts: the controlled territory, the highway occupancy by vehicles, the parking and the controlled territory are introduced. Technical realizabilityof organizing the necessary flow of information on the state of the transport system for its regulation has been marked. Sequence of practical implementation of the solution is given. An algorithm for predicting traffic congestion in the controlled transport system is suggested.

  19. Membrane trafficking of yeast transporters: mechanisms and physiological control of downregulation

    OpenAIRE

    Haguenauer-Tsapis, Rosine; André, Bruno

    2004-01-01

    Of the 125 plasma membrane transporters thus far identified in the yeast S. cerevisiae, a growing number is reported to be subject to tight control at membrane trafficking level, in addition to control at transcriptional level. Typical physiological conditions inducing these controls include changes of substrate concentration and availability of alternative nutrients. These changes of conditions often provoke the downregulation of specific transporters eventually accompanied by upregulation o...

  20. An intermodal traffic control strategy for private vehicle and public transport

    OpenAIRE

    BHOURI, N; LOTITO, P

    2005-01-01

    This paper proposes a traffic-responsive urban traffic control strategy allowing a real time passive public transport priority. The proposed strategy is based on a store and forward modeling of both of the private vehicle and Public transport traffic. The regulator is designed using the linear quadratic, which allows a traffic responsive co-ordinated control for wide-area networks. The objective of this strategy is to control the junctions traffic lights in order to improve the traffic perfor...

  1. 基于TRBAC混合模型的协同设计过程动态访问控制%Dynamic access control of collaborative design process based on TRBAC hybrid model

    Institute of Scientific and Technical Information of China (English)

    郭银章; 曾建潮

    2012-01-01

    Aiming at the access control problem of collaborative design process which included access control lifecycle constraint, access control number constraint and dynamic changes features, the Role-Based Access Control (RBAC) model and Task- Based Access Control (TBAC) model were extended and incorporated. At the same time, a CDACM model for dynamic access control in collaborative design was proposed. To realized context-sensitive subject and object dynamic authorization management, authorization state migration and access control constraint were controlled by introducing the state migration and constraint relation of design unit authorization structure. The problems of access time constraint and transaction integrity constraint were solved by setting the constraints of permission ac- tivating cycle time and permission access times. Moreover, access control policy and activation mechanism for collaborative design were given. The theoretical research was applied in the collaborative design access control system of chain-transportation, which tested the validity of the proposed model.%针对具有周期时间约束、访问次数限制和设计过程动态变化特点的协同设计过程访问控制问题,将基于角色的访问控制模型和基于任务的访问控制模型进行扩展与融合,提出一种适应于协同设计全过程的动态访问控制模型CDACM。通过引入设计单元结构体的状态迁移和约束依赖关系,控制访问授权状态的变化和权限的约束,以实现与上下文相关的主客体动态授权管理;同时通过设定权限激活周期时间约束和权限访问次数限制约束,来解决权限访问时间限制和事务完整性约束问题。给出协同设计的访问控制策略和激活机制。将理论研究应用于链式输送机协同设计访问控制系统中,验证了所提模型的有效性。

  2. Controls of macropore network characteristics on preferential solute transport

    Directory of Open Access Journals (Sweden)

    M. Larsbo

    2014-08-01

    Full Text Available In this study we examined the relationships between macropore network characteristics, hydraulic properties and state variables and measures of preferential transport in undisturbed columns sampled from four agricultural topsoils of contrasting texture and structure. Macropore network characteristics were computed from 3-dimensional X-ray tomography images of the soil pore system. Non-reactive solute transport experiments were carried out at five steady-state water flow rates from 2 to 12 mm h−1. The degree of preferential transport was evaluated by the normalised 5% solute arrival time and the apparent dispersivity calculated from the resulting breakthrough curves. Near-saturated hydraulic conductivities were measured on the same samples using a tension disk infiltrometer placed on top of the columns. Results showed that many of the macropore network characteristics were inter-correlated. For example, large macroporosities were associated with larger specific macropore surface areas and better local connectivity of the macropore network. Generally, an increased flow rate resulted in earlier solute breakthrough and a shifting of the peak concentration towards smaller drained volumes. Columns with smaller macroporosities, poorer local connectivity of the macropore network and smaller near-saturated hydraulic conductivities exhibited a greater degree of preferential transport. This can be explained by the fact that, with only two exceptions, global (i.e. sample-scale continuity of the macropore network was still preserved at low macroporosities. Thus, for any given flow rate pores of larger diameter were actively conducting solute in soils of smaller near-saturated hydraulic conductivity. With less time for equilibration between the macropores and the surrounding matrix the transport became more preferential. Conversely, the large specific macropore surface area and well-connected macropore networks associated with columns with large

  3. Analyzing the effect of routing protocols on media access control protocols in radio networks

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, C. L. (Christopher L.); Drozda, M. (Martin); Marathe, A. (Achla); Marathe, M. V. (Madhav V.)

    2002-01-01

    We study the effect of routing protocols on the performance of media access control (MAC) protocols in wireless radio networks. Three well known MAC protocols: 802.11, CSMA, and MACA are considered. Similarly three recently proposed routing protocols: AODV, DSR and LAR scheme 1 are considered. The experimental analysis was carried out using GloMoSim: a tool for simulating wireless networks. The main focus of our experiments was to study how the routing protocols affect the performance of the MAC protocols when the underlying network and traffic parameters are varied. The performance of the protocols was measured w.r.t. five important parameters: (i) number of received packets, (ii) average latency of each packet, (iii) throughput (iv) long term fairness and (v) number of control packets at the MAC layer level. Our results show that combinations of routing and MAC protocols yield varying performance under varying network topology and traffic situations. The result has an important implication; no combination of routing protocol and MAC protocol is the best over all situations. Also, the performance analysis of protocols at a given level in the protocol stack needs to be studied not locally in isolation but as a part of the complete protocol stack. A novel aspect of our work is the use of statistical technique, ANOVA (Analysis of Variance) to characterize the effect of routing protocols on MAC protocols. This technique is of independent interest and can be utilized in several other simulation and empirical studies.

  4. A Multi-Domain Access Control Infrastructure Based on Diameter and EAP

    Science.gov (United States)

    Ben Ayed, Souheil; Teraoka, Fumio

    The evolution of Internet, the growth of Internet users and the new enabled technological capabilities place new requirements to form the Future Internet. Many features improvements and challenges were imposed to build a better Internet, including securing roaming of data and services over multiple administrative domains. In this research, we propose a multi-domain access control infrastructure to authenticate and authorize roaming users through the use of the Diameter protocol and EAP. The Diameter Protocol is a AAA protocol that solves the problems of previous AAA protocols such as RADIUS. The Diameter EAP Application is one of Diameter applications that extends the Diameter Base Protocol to support authentication using EAP. The contributions in this paper are: 1) first implementation of Diameter EAP Application, called DiamEAP, capable of practical authentication and authorization services in a multi-domain environment, 2) extensibility design capable of adding any new EAP methods, as loadable plugins, without modifying the main part, and 3) provision of EAP-TLS plugin as one of the most secure EAP methods. DiamEAP Server basic performances were evaluated and tested in a real multi-domain environment where 200 users attempted to access network using the EAP-TLS method during an event of 4 days. As evaluation results, the processing time of DiamEAP using the EAP-TLS plugin for authentication of 10 requests is about 20ms while that for 400 requests/second is about 1.9 second. Evaluation and operation results show that DiamEAP is scalable and stable with the ability to handle more than 6 hundreds of authentication requests per second without any crashes. DiamEAP is supported by the AAA working group of the WIDE Project.

  5. Feed gas contaminant control in ion transport membrane systems

    Science.gov (United States)

    Carolan, Michael Francis; Minford, Eric; Waldron, William Emil

    2009-07-07

    Ion transport membrane oxidation system comprising an enclosure having an interior and an interior surface, inlet piping having an internal surface and adapted to introduce a heated feed gas into the interior of the enclosure, and outlet piping adapted to withdraw a product gas from the interior of the enclosure; one or more planar ion transport membrane modules disposed in the interior of the enclosure, each membrane module comprising mixed metal oxide material; and a preheater adapted to heat a feed gas to provide the heated feed gas to the inlet piping, wherein the preheater comprises an interior surface. Any of the interior surfaces of the enclosure, the inlet piping, and the preheater may be lined with a copper-containing metal lining. Alternatively, any of the interior surfaces of the inlet piping and the preheater may be lined with a copper-containing metal lining and the enclosure may comprise copper.

  6. Safe transport, use and disposal of nuclear medicine sources in India - Controls and administrative procedures

    International Nuclear Information System (INIS)

    Large number of applications of radioactive material (RAM) in medicine, industry, agriculture and research necessitates its transport from one place to another. In view of the radiation hazard associated with the transport of RAM, these are required to be transported in accordance with the national regulations. In India, Atomic Energy Regulatory Board (AERB), the Competent Authority, enforce the regulations for the safe transport of RAM through a Code. The code is based on the IAEA regulations for 'Safe Transport of Radioactive Material' with modifications to suit the conditions of transport specific to India. In India, a considerable supply of the radioisotopes, particularly short-lived, used in nuclear medicine, is of foreign origin and the quantum of such imports is increasing annually. In this paper, the current administrative procedures and controls followed for safe transport, use and disposal of RAM used in nuclear medicine in India are discussed in detail. (author)

  7. Efficiency of sediment transport by flood and its control in the Lower Yellow River

    Institute of Scientific and Technical Information of China (English)

    NI; Jinren; LIU; Xiaoyong; LI; Tianhong; ZHAO; Yean; JIN; L

    2004-01-01

    This paper presents the characteristics of sediment transport by flood in the Lower Yellow River with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on Water Use for Sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower Yellow River, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 20 kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower Yellow River were also simulated. For the case of sediment concentration being 20 kg/m3, the optimized controlling discharge ranges from 2390 to 2900 m3/s in the lower reach of Huayuankou.This study is also of significance to flood control and flushing sediment in the Lower Yellow River with proper operation modes of Xiaolangdi Reservoir.

  8. Chemical and mechanical control of corrosion product transport

    Energy Technology Data Exchange (ETDEWEB)

    Hede Larsen, O.; Blum, R. [I/S Fynsvaerket, Faelleskemikerne, Odense (Denmark); Daucik, K. [I/S Skaerbaekvaerket, Faelleskemikerne, Fredericia (Denmark)

    1996-12-01

    The corrosion products formed in the condensate and feedwater system of once-through boilers are precipitated and deposited inside the evaporator tubes mainly in the burner zone at the highest heat flux. Depositions lead to increased oxidation rate and increased metal temperature of the evaporator tubes, hereby decreasing tube lifetime. This effect is more important in the new high efficiency USC boilers due to increased feedwater temperature and hence higher thermal load on the evaporator tubes. The only way to reduce the load on the evaporator tubes is to minimise corrosion product transport to the boiler. Two general methods for minimising corrosion product transport to the boiler have been evaluated through measurement campaigns for Fe in the water/steam cycle in supercritical boilers within the ELSAM area. One method is to reduce corrosion in the low temperature condensate system by changing conditioning mode from alkaline volatile treatment (AVT) to oxygenated treatment (OT). The other method is to filtrate part of the condensate with a mechanical filter at the deaerator. The results show, that both methods are effective at minimising Fe-transport to the boiler, but changing to OT has the highest effect and should always be used, whenever high purity condensate is maintained. Whether mechanical filtration also is required, depends on the boiler, specifically the load on the evaporator. A simplified calculation model for lifetime evaluation of evaporator tubes has been developed. This model has been used for evaluating the effect of corrosion product transport to the boiler on evaporator tube lifetime. Conventional supercritical boilers generally can achieve sufficient lifetime by AVT and even better by OT, whereas all measures to reduce Fe-content of feedwater, including OT and mechanical filtration, should be taken, to ensure sufficient lifetime for the new boilers with advanced steam data - 290 bar/580 deg. C and above. (au)

  9. Stoichiometry-Control of Electronic Transport at Complex Oxide Interface

    Science.gov (United States)

    Xu, Peng; Jalan, Bharat

    2014-03-01

    Employing the hybrid molecular beam epitaxy approach to grow NdTiO3/SrTiO3 heterostructures - a polar/nonpolar system sharing many similarities with LaAlO3/SrTiO3 with an added functionality of NdTiO3 being an antiferromagnetic Mott insulator- we will present a detailed film growth and transport study as a function of cation stoichiometry in NdTiO3. Irrespective of the cation stoichiometry (measured by high resolution x-ray diffraction and x-ray photoelectron spectroscopy), films grew in an atomic layer-by-layer fashion as evidenced by the reflection high-energy electron diffraction intensity oscillations, and films showed a temperature dependent metal-to-insulator (M-I) type behavior. Remarkably, TMI was found to increase irrespective of whether films were Nd- or Ti-rich. Furthermore, hall measurement of a 3.5 nm NdTiO3 film grown on 3 nm SrTiO3 layer on LSAT substrate revealed n type carrier density, 3 x 1014 cm-2 for stoichiometric samples, which would be consistent with the interface conduction due to an interfacial polar discontinuity effect. Using detailed temperature dependent magneto-transport measurements, we will present a comprehensive study of correlation between film stoichiometry, interface conduction, and transport mechanisms.

  10. Control of electron transport routes through redox-regulated redistribution of respiratory complexes

    OpenAIRE

    Liu, Lu-Ning; Samantha J Bryan; Huang, Fang; Yu, Jianfeng; Nixon, Peter J.; Rich, Peter R.; Mullineaux, Conrad W.

    2012-01-01

    In cyanobacteria, respiratory electron transport takes place in close proximity to photosynthetic electron transport, because the complexes required for both processes are located within the thylakoid membranes. The balance of electron transport routes is crucial for cell physiology, yet the factors that control the predominance of particular pathways are poorly understood. Here we use a combination of tagging with green fluorescent protein and confocal fluorescence microscopy in live cells o...

  11. System and method for air temperature control in an oxygen transport membrane based reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Sean M

    2016-09-27

    A system and method for air temperature control in an oxygen transport membrane based reactor is provided. The system and method involves introducing a specific quantity of cooling air or trim air in between stages in a multistage oxygen transport membrane based reactor or furnace to maintain generally consistent surface temperatures of the oxygen transport membrane elements and associated reactors. The associated reactors may include reforming reactors, boilers or process gas heaters.

  12. Apama平台下访问控制的实现%Implementation of Access Control in Apama Platform

    Institute of Scientific and Technical Information of China (English)

    陈树江

    2011-01-01

    访问控制是通过某种途径来准许或是限制主体对客体访问能力及范围的一种方法。本文结合Apama应用的特点,选择了基于角色的访问控制模型(Role-Based Access Control,RBAC)。根据此模型,把Apama平台下的访问控制实现分成了两个阶段:在用户身份认证阶段,结合JAAS(Java Authentication and Authorization Service)技术,采用了合适的认证机制和配置,并对此进行了设计和实现;在授权控制阶段,根据Apama平台下受保护资源的特点,合理设计访问策略,利用此策略实现授权控制。%Abstract:Access control is used to permit or limit user's access to objects by some means.It's better to use role-based access control according to the characteristic of Apama application. With RBAC, this paper divides the implementation of access control into two phases: in the part of user authentication, combined with JAAS, this paper designs and implements user authentication by means of proper authentication mechanism and configuration; in the part of user authorization, it also designs access policy according to the characteristic of protected data and implements the access control with it.

  13. The IEO Data Center Management System: Tools for quality control, analysis and access marine data

    Science.gov (United States)

    Casas, Antonia; Garcia, Maria Jesus; Nikouline, Andrei

    2010-05-01

    Since 1994 the Data Centre of the Spanish Oceanographic Institute develops system for archiving and quality control of oceanographic data. The work started in the frame of the European Marine Science & Technology Programme (MAST) when a consortium of several Mediterranean Data Centres began to work on the MEDATLAS project. Along the years, old software modules for MS DOS were rewritten, improved and migrated to Windows environment. Oceanographic data quality control includes now not only vertical profiles (mainly CTD and bottles observations) but also time series of currents and sea level observations. New powerful routines for analysis and for graphic visualization were added. Data presented originally in ASCII format were organized recently in an open source MySQL database. Nowadays, the IEO, as part of SeaDataNet Infrastructure, has designed and developed a new information system, consistent with the ISO 19115 and SeaDataNet standards, in order to manage the large and diverse marine data and information originated in Spain by different sources, and to interoperate with SeaDataNet. The system works with data stored in ASCII files (MEDATLAS, ODV) as well as data stored within the relational database. The components of the system are: 1.MEDATLAS Format and Quality Control - QCDAMAR: Quality Control of Marine Data. Main set of tools for working with data presented as text files. Includes extended quality control (searching for duplicated cruises and profiles, checking date, position, ship velocity, constant profiles, spikes, density inversion, sounding, acceptable data, impossible regional values,...) and input/output filters. - QCMareas: A set of procedures for the quality control of tide gauge data according to standard international Sea Level Observing System. These procedures include checking for unexpected anomalies in the time series, interpolation, filtering, computation of basic statistics and residuals. 2. DAMAR: A relational data base (MySql) designed to

  14. Access Control List Technology Studying and Application%ACL技术研究及应用

    Institute of Scientific and Technical Information of China (English)

    杨梅; 杨平利; 宫殿庆

    2011-01-01

    Access control list (ACL) refers to the dictation list of router joint, which forms an orderly condition collection by a group of permit an deny sentences to control the data package of controlling the port turnover. ACL is a technology, which uses data stream classification and filtration to improve network's security. ACL is also a service level agreement ( SLA), which is used to enhance the quality of service in network. Introduce in detail about ACL's conception, classification, principle and function. The typical applications are discussed in some cases, which display the method of how to use ACL. It also presents the matching principle and some advice to reduce making mistakes when use the ACL.%访问控制列表是路由交换设备的一组条件控制指令列表,是实现包过滤技术的核心内容,它是一种数据流分类和过滤技术,在网络安全中发挥着重要的作用;访问控制列表也是一种服务级别协定,用于支持和提高网络的服务质量.首先介绍了访问控制列表的定义、分类、工作原理和功能,其次以实例的方式给出了访问控制列表的几种典型应用,通过应用实例说明了访问控制列表在网络安全中具体使用方法和特点,最后给配置使用时的要点、规则和使用时的建议.

  15. A Nonlinear Dynamic Inversion Predictor-Based Model Reference Adaptive Controller for a Generic Transport Model

    Science.gov (United States)

    Campbell, Stefan F.; Kaneshige, John T.

    2010-01-01

    Presented here is a Predictor-Based Model Reference Adaptive Control (PMRAC) architecture for a generic transport aircraft. At its core, this architecture features a three-axis, non-linear, dynamic-inversion controller. Command inputs for this baseline controller are provided by pilot roll-rate, pitch-rate, and sideslip commands. This paper will first thoroughly present the baseline controller followed by a description of the PMRAC adaptive augmentation to this control system. Results are presented via a full-scale, nonlinear simulation of NASA s Generic Transport Model (GTM).

  16. URSA: Ubiquitous and Robust Access Control for Mobile Ad Hoc Networks

    OpenAIRE

    Luo, Haiyun; Kong, Jiejun; Zerfos, Petros; Lu, Songwu; Zhang, Lixia

    2004-01-01

    Restricting network access of routing and packet forwarding to well-behaving nodes and denying access from misbehaving nodes are critical for the proper functioning of a mobile ad-hoc network where cooperation among all networking nodes is usually assumed. However, the lack of a network infrastructure, the dynamics of the network topology and node membership, and the potential attacks from inside the network by malicious and/or noncooperative selfish nodes make the conventional network access...

  17. Presidential Management Fellows (PMF) Talent Acquisition System, PMF-TAS (ACCESS CONTROLLED)

    Data.gov (United States)

    Office of Personnel Management — Application and Assessment system for Presidential Management Fellows (PMF) and PMF Science, Technology, Engineering, and Math (STEM) programs. This sytem is access...

  18. Si Nanopores Development for External Control of Transport of Biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Ileri, N; Tringe, J; Letant, S; Palozoglu, A; Stroeve, P; Faller, R

    2008-06-13

    Nazar Ileri has been involved in an independent, multidisciplinary effort to create a new class of molecular sieves for proteins and viruses. Her experimental work has been performed concurrently at two campuses, LLNL and UC Davis, while theoretical components have been largely accomplished at UC Davis. As will be described, the devices she is creating have great potential to improve very significantly the efficiency and selectivity of molecular transport over what is presently available from state-of-the-art membranes. Our biotechnology training program is based on an integrated study of the transport of biomolecules through conically-shaped, nanoporous silicon membranes. The overall objective of this effort is to demonstrate an efficient, highly selective membrane technology that is manufacturable for macroscopic areas and can be employed in sensing, diagnostic and biomedical applications. Our specific aims are to (1) fabricate and characterize the physical characteristics of the membranes, (2) to demonstrate their utility for molecular transport and separation, and (3) to develop models that will facilitate understanding of these devices as well as improved performance of the next generation of devices. We have proposed that the conical pores have superior performance characteristics compared to other porous filters. To study this hypothesis, complementary approaches from different disciplines, such as membrane synthesis, experiment, and molecular simulation need to be combined. This provides an ideal training environment for a future leader in biotechnology. Hence, for this study, Nazar Ileri has started to carry out a full range of experimental and theoretical investigations under our guidance. First, she has begun fabrication of filters with conical/pyramidal pores. She characterized the pores by AFM and SEM, and analyzed the images using wavelets and other mathematical tools. She has also started to conduct biomolecule transport experiments to compare the

  19. Underwater acoustic sensor networks: Medium access control, routing and reliable transfer

    Science.gov (United States)

    Xie, Peng

    Recently there have been growing interests in monitoring aquatic environments for scientific exploration, commercial exploitation and coastline protection. The ideal vehicle for this type of extensive monitoring is a mobile underwater sensor network (M-UWSN), consisting of a large number of low cost underwater sensors that can move with water currents and dispersion. M-UWSNs are significantly different from terrestrial sensor networks: (1) Radio channels do not work well under water. They must be replaced by acoustic channels, which feature long propagation delays, low communication bandwidth and high channel error rates; (2) While most ground sensors are static, underwater sensor nodes may move with water currents (and other underwater activities), as introduces passive sensor mobility. Due to the very different environment properties and the unique characteristics of acoustic channels, the protocols developed for terrestrial sensor networks are not applicable to M-UWSNs, and new research at every level of the protocol suite is demanded. In this dissertation work, we investigate three fundamental networking problems in M-UWSN design: medium access control, multi-hop routing and reliable data transfer. (1) Medium access control (MAC): the long propagation delays and narrow communication bandwidth of acoustic channels pose the major challenges to the energy-efficient MAC design in M-UWSNs. For the first time, we formally investigate the random access and RTS/CTS techniques in networks with long propagation delays and low communication bandwidth (as in M-UWSNs). Based on this study, we propose a novel reservation-based MAC approach, called R-MAC, for dense underwater sensor networks with unevenly distributed (spatially and temporally) traffic. Simulation results show that R-MAC is not only energy efficient but also supports fairness. (2) Multi-hop routing: In M-UWSNs, energy efficiency and mobility handling are the two major concerns for multi-hop routing, which have

  20. Controlling polymer translocation and ion transport via charge correlations.

    Science.gov (United States)

    Buyukdagli, Sahin; Ala-Nissila, T

    2014-11-01

    We develop a correlation-corrected transport theory in order to predict ionic and polymer transport properties of membrane nanopores under physical conditions where mean-field electrostatics breaks down. The experimentally observed low KCl conductivity of open α-hemolysin pores is quantitatively explained by the presence of surface polarization effects. Upon the penetration of a DNA molecule into the pore, these polarization forces combined with the electroneutrality of DNA sets a lower boundary for the ionic current, explaining the weak salt dependence of blocked pore conductivities at dilute ion concentrations. The addition of multivalent counterions to the solution results in the reversal of the polymer charge and the direction of the electroosmotic flow. With trivalent spermidine or quadrivalent spermine molecules, the charge inversion is strong enough to stop the translocation of the polymer and to reverse its motion. This mechanism can be used efficiently in translocation experiments in order to improve the accuracy of DNA sequencing by minimizing the translocation velocity of the polymer. PMID:25310861

  1. Improvement in Medium Access Control protocol based on new contention scheme for wireless ad hoc network

    Directory of Open Access Journals (Sweden)

    C.Ellammal

    2012-05-01

    Full Text Available In todays wireless networks, stations using the IEEE 802.11 standard contend for the channel using the Distributed Coordination Function (DCF. Research has shown that DCF€™s performance degrades especially with the large number of stations. This becomes more concerning due to the increasing proliferation of wireless devices. In this paper, we present a Medium Access Control (MAC scheme for wireless LANs and compare its performance to DCF . Our scheme, which attempts to resolve the contention in a constant number of slots (or constant time, is called CONSTI. The contention resolution happens over a predefined number of slots. In a slot, the stations probabilistically send a jam signal on the channel. The stations listening retire if they hear a jam signal. The others continue to the next slot. Over several slots, we aim to have one station remaining in the contention, which will then transmit its data. We find the optimal parameters of CONSTI and present an analysis on its performance.

  2. Controlling the taste receptor accessible structure of rebaudioside A via binding to bovine serum albumin.

    Science.gov (United States)

    Mudgal, Samriddh; Keresztes, Ivan; Feigenson, Gerald W; Rizvi, S S H

    2016-04-15

    We illustrate a method that uses bovine serum albumin (BSA) to control the receptor-accessible part of rebaudioside A (Reb A). The critical micelle concentration (CMC) of Reb A was found to be 4.5 mM and 5 mM at pH 3 and 6.7 respectively. NMR studies show that below its CMC, Reb A binds weakly to BSA to generate a Reb A-protein complex ("RPC"), which is only modestly stable under varying conditions of pH (3.0-6.7) and temperature (4-40°C) with its binding affinities determined to be in the range of 5-280 mM. Furthermore, saturation transfer difference (STD) NMR experiments confirm that the RPC has fast exchange of the bitterness-instigating diterpene of Reb A into the binding sites of BSA. Our method can be used to alter the strength of Reb A-receptor interaction, as a result of binding of Reb A to BSA, which may ultimately lead to moderation of its taste.

  3. A Combined Solution for Routing and Medium Access Control Layer Attacks in Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    R. Murugan

    2010-01-01

    Full Text Available Problem statement: In Mobile Ad hoc Network (MANET, both the routing layer and the Medium Access Control (MAC layer are vulnerable to several attacks. There are very few techniques to detect and isolate the attacks of both these layers simultaneously. In this study, we developed a combined solution for routing and MAC layer attacks. Approach: Our approach, makes use of three techniques simultaneously which consists of a cumulative frequency based detection technique for detecting MAC layers attacks, data forwarding behavior based detection technique for detecting packet drops and message authentication code based technique for packet modification. Results: Our combined solution presents a reputation value for detecting the malicious nodes and isolates them from further network participation till its revocation. Our approach periodically checks all nodes, including the isolated nodes, at regular time period λ. A node which recovers from its misbehaving condition is revoked to its normal condition after the time period λ. Conclusion/Recommendations: By simulation results, we show that our combined solution provides more security by increased packet delivery ratio and reduced packet drops. We also shown that our approach has less overhead compared to the existing technique.

  4. Authenticated Blind Issuing of Symmetric Keys for Mobile Access Control System without Trusted Parties

    Directory of Open Access Journals (Sweden)

    Shin-Yan Chiou

    2013-01-01

    Full Text Available Mobile authentication can be used to verify a mobile user’s identity. Normally this is accomplished through the use of logon passwords, but this can raise the secret-key agreement problem between entities. This issue can be resolved by using a public-key cryptosystem, but mobile devices have limited computation ability and battery capacity and a PKI is needed. In this paper, we propose an efficient, non-PKI, authenticated, and blind issued symmetric key protocol for mobile access control systems. An easy-to-deploy authentication and authenticated key agreement system is designed such that empowered mobile devices can directly authorize other mobile devices to exchange keys with the server upon authentication using a non-PKI system without trusted parties. Empowered mobile users do not know the key value of the other mobile devices, preventing users from impersonating other individuals. Also, for security considerations, this system can revoke specific keys or keys issued by a specific user. The scheme is secure, efficient, and feasible and can be implemented in existing environments.

  5. Ongoing spontaneous activity controls access to consciousness: a neuronal model for inattentional blindness.

    Directory of Open Access Journals (Sweden)

    Stanislas Dehaene

    2005-05-01

    Full Text Available Even in the absence of sensory inputs, cortical and thalamic neurons can show structured patterns of ongoing spontaneous activity, whose origins and functional significance are not well understood. We use computer simulations to explore the conditions under which spontaneous activity emerges from a simplified model of multiple interconnected thalamocortical columns linked by long-range, top-down excitatory axons, and to examine its interactions with stimulus-induced activation. Simulations help characterize two main states of activity. First, spontaneous gamma-band oscillations emerge at a precise threshold controlled by ascending neuromodulator systems. Second, within a spontaneously active network, we observe the sudden "ignition" of one out of many possible coherent states of high-level activity amidst cortical neurons with long-distance projections. During such an ignited state, spontaneous activity can block external sensory processing. We relate those properties to experimental observations on the neural bases of endogenous states of consciousness, and particularly the blocking of access to consciousness that occurs in the psychophysical phenomenon of "inattentional blindness," in which normal subjects intensely engaged in mental activity fail to notice salient but irrelevant sensory stimuli. Although highly simplified, the generic properties of a minimal network may help clarify some of the basic cerebral phenomena underlying the autonomy of consciousness.

  6. 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.

  7. An energy-efficient media access control protocol for chain-type wireless sensor networks

    Science.gov (United States)

    Wang, Yu; Chen, Chang Wen

    2005-06-01

    We present in this paper an energy efficient media access control (MAC) protocol for chain-type wireless sensor networks. The chain-type sensor networks are fundamentally different from traditional sensor networks in that the sensor nodes in this class of networks are deployed along narrow and elongated geographical areas and form a chain-type topology. Recently, we have successfully developed hierarchical network architecture, sensor deployment strategy, and corresponding network initialization and operation protocols for this class of sensor networks. In this paper, we present a novel TDMA scheduling protocol that takes full advantages of the available channel reuse inherent in the chain-type sensor networks to develop energy efficient and high data throughput MAC protocols for sensor data transmission. The synchronized TDMA scheduling allows the nodes to power on only when it is scheduled to send and receive and therefore results in additional energy saving. Within a cluster, parallel transmission is made possible because of the linear distribution of nodes within the chain-type topology and this yields the desired high throughput. Preliminary simulations have been carried out to show that the proposed TDMA scheduling outperforms the well-know SMAC scheme in terms of energy efficiency and data throughput under various duty cycles.

  8. Choosing between global and local emission control strategies in urban transport sector, which way to go?

    OpenAIRE

    Sudhakar Yedla

    2007-01-01

    Cities are engrossed with response strategies for the control of local pollution from transport sector. However, as the transport sector has been growing as major GHG contributor, and there is an increasing scope for investment and support from the international financial institutions, cities often get into confusion on whether to go by local emission control strategies (LEMS) or adopt GHG mitigation strategies (GEMS). This paper presents a comparison between GHG mitigation strategies and loc...

  9. An Effective Security Mechanism for M-Commerce Applications Exploiting Ontology Based Access Control Model for Healthcare System

    Directory of Open Access Journals (Sweden)

    S.M. Roychoudri

    2016-09-01

    Full Text Available Health organizations are beginning to move mobile commerce services in recent years to enhance services and quality without spending much investment for IT infrastructure. Medical records are very sensitive and private to any individuals. Hence effective security mechanism is required. The challenges of our research work are to maintain privacy for the users and provide smart and secure environment for accessing the application. It is achieved with the help of personalization. Internet has provided the way for personalization. Personalization is a term which refers to the delivery of information that is relevant to individual or group of individuals in the format, layout specified and in time interval. In this paper we propose an Ontology Based Access Control (OBAC Model that can address the permitted access control among the service providers and users. Personal Health Records sharing is highly expected by the users for the acceptance in mobile commerce applications in health care systems.

  10. An Ounce of Prevention: Technologists Use Network-Access Control to Protect System Resources, Students

    Science.gov (United States)

    Bolch, Matt

    2009-01-01

    Whether for an entire district, a single campus, or one classroom, allowing authorized access to a computer network can be fraught with challenges. The login process should be fairly seamless to approved users, giving them speedy access to approved Web sites, databases, and other sources of information. It also should be tough on unauthorized…

  11. Explicit window-based transport control protocols in lossy environments

    OpenAIRE

    de Vleeschouwer, C.; Frossard, P.

    2004-01-01

    This paper addresses efficient packet loss recovery by retransmission in window-based congestion control protocols. It builds on explicit congestion control mechanisms to decouple the packet loss detection from the congestion feedback signals. Implicit algorithms alternatively infer congestion from losses (which yields to window size reduction), and therefore do not allow to evaluate the performance of window-based transmission algorithms in lossy environments. We first propose a simple modif...

  12. Simulation-Based Planning and Control of Transport Flows in Port Logistic Systems

    Directory of Open Access Journals (Sweden)

    Antonio Diogo Passos Lima

    2015-01-01

    Full Text Available In highly dynamic and uncertain transport conditions, transport transit time has to be continuously monitored so that the service level is ensured at a proper cost. The aim of this research is to propose and to test a procedure which allows an agile planning and control of transport flows in port logistic systems. The procedure couples an agent-based simulation and a queueing theory model. In this paper, the transport scheduling performed by an agent at the intermodal terminal was taken into consideration. The decision-making agent takes into account data which is acquired in remote points of the system. The obtained results indicate the relevance of continuously considering, for the transport planning and control, the expected transit time and further waiting times along port logistic systems.

  13. Experimental control of transport resonances in a coherent quantum rocking ratchet.

    Science.gov (United States)

    Grossert, Christopher; Leder, Martin; Denisov, Sergey; Hänggi, Peter; Weitz, Martin

    2016-01-01

    The ratchet phenomenon is a means to get directed transport without net forces. Originally conceived to rectify stochastic motion and describe operational principles of biological motors, the ratchet effect can be used to achieve controllable coherent quantum transport. This transport is an ingredient of several perspective quantum devices including atomic chips. Here we examine coherent transport of ultra-cold atoms in a rocking quantum ratchet. This is realized by loading a rubidium atomic Bose-Einstein condensate into a periodic optical potential subjected to a biharmonic temporal drive. The achieved long-time coherence allows us to resolve resonance enhancement of the atom transport induced by avoided crossings in the Floquet spectrum of the system. By tuning the strength of the temporal modulations, we observe a bifurcation of a single resonance into a doublet. Our measurements reveal the role of interactions among Floquet eigenstates for quantum ratchet transport. PMID:26852803

  14. Effects of high-frequency electromagnetic fields emitted from card readers of access control systems on electronic pocket dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Deji, Shizuhiko [Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan); Nishizawa, Kunihide [Radioisotope Research Center, Nagoya University, Furo-cho, Chlkusa-ku, Nagoya 464-8602 (Japan)]. E-mail: j45616a@nucc.cc.nagoya-u.ac.jp

    2005-06-01

    High-frequency electromagnetic fields in the 120 kHz band emitted from card readers for access control systems caused abnormally high doses on electronic pocket dosimeters (EPDs). All EPDs recovered their normal performance by resetting after the exposure ceased. The electric and magnetic immunity levels of the EPDs were estimated by using the distances needed to prevent electromagnetic interference.

  15. Use of the tools of an operating system kernel to control access to the entities of application servers

    International Nuclear Information System (INIS)

    A method has been proposed for using the tools of kernel of an operating system to control access to the entities of application servers. The possibility of using an information protection system incorporated into the operating system to store and implement security policy has been demonstrated for a database management system

  16. Atomic-Scale Control of Electron Transport through Single Molecules

    DEFF Research Database (Denmark)

    Wang, Y. F.; Kroger, J.; Berndt, R.;

    2010-01-01

    Tin-phthalocyanine molecules adsorbed on Ag(111) were contacted with the tip of a cryogenic scanning tunneling microscope. Orders-of-magnitude variations of the single-molecule junction conductance were achieved by controllably dehydrogenating the molecule and by modifying the atomic structure of...

  17. Fuel efficiency and fouling control coatings in maritime transport

    DEFF Research Database (Denmark)

    Lindholdt, Asger

    First, this thesis concerns the drag performance of fouling control coatings (FCCs) used to protect hulls on ships against biofouling and, therefore, minimize any drag therefrom. A systematic overview of the literature and description of the experimental methods used to quantify the drag of FCCs...

  18. 细粒度角色访问控制%Finely Granular Access Control Based on RBAC

    Institute of Scientific and Technical Information of China (English)

    方卫青

    2011-01-01

    分析基于角色访问控制的模型,在此基础上提出了一种在面向对象的编程模式中基于细粒度权限控制的管理方法.利用对象的继承特性引入细粒度权限管理的概念,把资源的控制从菜单粒度分解到原子操作粒度.分解后的权限和角色建立关系,通过给用户分配角色建立权限和用户的关系,从而简化了权限的管理.最后给出了具体的实现过程,在实际中得到了应用,验证了此方法的正确性和可行性.%Based on the theory of role-based access control, a method of finely granular access control in object orient programming is proposed in this paper. Introducing the idea about finely granular access control through Inherit attributes of object, decomposes the access privilege from menu to atom control. The privilege is assigned to role, then access control can be manage easily by defining the user of the role to simplify management of permissions. Finally, the specific implementation process has been applied in practice to verify the correctness and feasibility of this method.

  19. Medium access control and hardware prototype designs for low-energy wireless sensor networks

    Energy Technology Data Exchange (ETDEWEB)

    Kohvakka, M.

    2009-07-01

    A Wireless Sensor Network (WSN) is an emerging technology consisting of small, cheap, and ultra-low energy sensor nodes, which cooperatively monitor physical quantities, actuate, and perform data processing tasks. A deployment may comprise thousands of randomly distributed autonomous nodes, which must self-configure and create a multi-hop network topology.This thesis focuses on low-energy WSNs targeting to long network lifetime. The main research problem is the combination of adaptive and scalable multi-hop networking with constrained energy budget, processing power, and communication bandwidth. The research problem is approached by energy-efficient protocols and low-power sensor node platforms. The main contribution of this thesis is an energy-efficient Medium Access Control (MAC) design for TUTWSN (Tampere University of Technology Wireless Sensor Network). The design comprises channel access and networking mechanisms, which specify data exchange, link synchronization, network self-configuration, and neighbor discovery operations. The second outcome are several low-power sensor node platforms, which have been designed and implemented to evaluate the performance of the MAC design and hardware components in real deployments. The third outcome are the performance models and analysis of several MAC designs including TUTWSN, IEEE 802.15.4, and the most essential research proposals.The results and conclusion of this Thesis indicate that it is possible to implement multi-hop WSNs in harsh and dynamic operation conditions with years of lifetime using current low-cost components and batteries. Energy analysis results indicate that the lowest energy consumption is achieved by using simple and high data-rate transceivers. It is also critical to minimize sleep mode power consumption of all components and to use accurate wake-up timers. However, the selection of components constitutes only a minor part of the solution, and an energy-efficient MAC layer design being able to

  20. ENERGY RESOURCE TRANSPORTATION BY COUNTRIES WITH NO ACCESS TO THE OPEN SEA(AN AZERBAIJAN CASE STUDY)

    OpenAIRE

    Ibrahimov, Rovshan

    2011-01-01

    Azerbaijan is pursuing a targeted policy that envisages maintaining reliable transport corridors and diversification of hydrocarbon deliveries to the world markets. This article looks at the strategies and tactical steps Azerbaijan is taking to reach the above-mentioned goals.