A service-oriented data access control model
NASA Astrophysics Data System (ADS)
Meng, Wei; Li, Fengmin; Pan, Juchen; Song, Song; Bian, Jiali
2017-01-01
The development of mobile computing, cloud computing and distributed computing meets the growing individual service needs. Facing with complex application system, it's an urgent problem to ensure real-time, dynamic, and fine-grained data access control. By analyzing common data access control models, on the basis of mandatory access control model, the paper proposes a service-oriented access control model. By regarding system services as subject and data of databases as object, the model defines access levels and access identification of subject and object, and ensures system services securely to access databases.
Dynamic access control model for privacy preserving personalized healthcare in cloud environment.
Son, Jiseong; Kim, Jeong-Dong; Na, Hong-Seok; Baik, Doo-Kwon
2015-01-01
When sharing and storing healthcare data in a cloud environment, access control is a central issue for preserving data privacy as a patient's personal health data may be accessed without permission from many stakeholders. Specifically, dynamic authorization for the access of data is required because personal health data is stored in cloud storage via wearable devices. Therefore, we propose a dynamic access control model for preserving the privacy of personal healthcare data in a cloud environment. The proposed model considers context information for dynamic access. According to the proposed model, access control can be dynamically determined by changing the context information; this means that even for a subject with the same role in the cloud, access permission is defined differently depending on the context information and access condition. Furthermore, we experiment the ability of the proposed model to provide correct responses by representing a dynamic access decision with real-life personalized healthcare system scenarios.
Task Delegation Based Access Control Models for Workflow Systems
NASA Astrophysics Data System (ADS)
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.
Access control and privilege management in electronic health record: a systematic literature review.
Jayabalan, Manoj; O'Daniel, Thomas
2016-12-01
This study presents a systematic literature review of access control for electronic health record systems to protect patient's privacy. Articles from 2006 to 2016 were extracted from the ACM Digital Library, IEEE Xplore Digital Library, Science Direct, MEDLINE, and MetaPress using broad eligibility criteria, and chosen for inclusion based on analysis of ISO22600. Cryptographic standards and methods were left outside the scope of this review. Three broad classes of models are being actively investigated and developed: access control for electronic health records, access control for interoperability, and access control for risk analysis. Traditional role-based access control models are extended with spatial, temporal, probabilistic, dynamic, and semantic aspects to capture contextual information and provide granular access control. Maintenance of audit trails and facilities for overriding normal roles to allow full access in emergency cases are common features. Access privilege frameworks utilizing ontology-based knowledge representation for defining the rules have attracted considerable interest, due to the higher level of abstraction that makes it possible to model domain knowledge and validate access requests efficiently.
Security middleware infrastructure for DICOM images in health information systems.
Kallepalli, Vijay N V; Ehikioya, Sylvanus A; Camorlinga, Sergio; Rueda, Jose A
2003-12-01
In health care, it is mandatory to maintain the privacy and confidentiality of medical data. To achieve this, a fine-grained access control and an access log for accessing medical images are two important aspects that need to be considered in health care systems. Fine-grained access control provides access to medical data only to authorized persons based on priority, location, and content. A log captures each attempt to access medical data. This article describes an overall middleware infrastructure required for secure access to Digital Imaging and Communication in Medicine (DICOM) images, with an emphasis on access control and log maintenance. We introduce a hybrid access control model that combines the properties of two existing models. A trust relationship between hospitals is used to make the hybrid access control model scalable across hospitals. We also discuss events that have to be logged and where the log has to be maintained. A prototype of security middleware infrastructure is implemented.
Atom-Role-Based Access Control Model
NASA Astrophysics Data System (ADS)
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.
Spatiotemporal access model based on reputation for the sensing layer of the IoT.
Guo, Yunchuan; Yin, Lihua; Li, Chao; Qian, Junyan
2014-01-01
Access control is a key technology in providing security in the Internet of Things (IoT). The mainstream security approach proposed for the sensing layer of the IoT concentrates only on authentication while ignoring the more general models. Unreliable communications and resource constraints make the traditional access control techniques barely meet the requirements of the sensing layer of the IoT. In this paper, we propose a model that combines space and time with reputation to control access to the information within the sensing layer of the IoT. This model is called spatiotemporal access control based on reputation (STRAC). STRAC uses a lattice-based approach to decrease the size of policy bases. To solve the problem caused by unreliable communications, we propose both nondeterministic authorizations and stochastic authorizations. To more precisely manage the reputation of nodes, we propose two new mechanisms to update the reputation of nodes. These new approaches are the authority-based update mechanism (AUM) and the election-based update mechanism (EUM). We show how the model checker UPPAAL can be used to analyze the spatiotemporal access control model of an application. Finally, we also implement a prototype system to demonstrate the efficiency of our model.
Formalization of the Access Control on ARM-Android Platform with the B Method
NASA Astrophysics Data System (ADS)
Ren, Lu; Wang, Wei; Zhu, Xiaodong; Man, Yujia; Yin, Qing
2018-01-01
ARM-Android is a widespread mobile platform with multi-layer access control mechanisms, security-critical in the system. Many access control vulnerabilities still exist due to the course-grained policy and numerous engineering defects, which have been widely studied. However, few researches focus on the mechanism formalization, including the Android permission framework, kernel process management and hardware isolation. This paper first develops a comprehensive formal access control model on the ARM-Android platform using the B method, from the Android middleware to hardware layer. All the model specifications are type checked and proved to be well-defined, with 75%of proof obligations demonstrated automatically. The results show that the proposed B model is feasible to specify and verify access control schemes in the ARM-Android system, and capable of implementing a practical control module.
An improved task-role-based access control model for G-CSCW applications
NASA Astrophysics Data System (ADS)
He, Chaoying; Chen, Jun; Jiang, Jie; Han, Gang
2005-10-01
Access control is an important and popular security mechanism for multi-user applications. GIS-based Computer Supported Cooperative Work (G-CSCW) application is one of such applications. This paper presents an improved Task-Role-Based Access Control (X-TRBAC) model for G-CSCW applications. The new model inherits the basic concepts of the old ones, such as role and task. Moreover, it has introduced two concepts, i.e. object hierarchy and operation hierarchy, and the corresponding rules to improve the efficiency of permission definition in access control models. The experiments show that the method can simplify the definition of permissions, and it is more applicable for G-CSCW applications.
Reflective Database Access Control
ERIC Educational Resources Information Center
Olson, Lars E.
2009-01-01
"Reflective Database Access Control" (RDBAC) is a model in which a database privilege is expressed as a database query itself, rather than as a static privilege contained in an access control list. RDBAC aids the management of database access controls by improving the expressiveness of policies. However, such policies introduce new interactions…
Typing for Conflict Detection in Access Control Policies
NASA Astrophysics Data System (ADS)
Adi, Kamel; Bouzida, Yacine; Hattak, Ikhlass; Logrippo, Luigi; Mankovskii, Serge
In this paper we present an access control model that considers both abstract and concrete access control policies specifications. Permissions and prohibitions are expressed within this model with contextual conditions. This situation may lead to conflicts. We propose a type system that is applied to the different rules in order to check for inconsistencies. If a resource is well typed, it is guaranteed that access rules to the resource contain no conflicts.
Spatiotemporal Access Model Based on Reputation for the Sensing Layer of the IoT
Guo, Yunchuan; Yin, Lihua; Li, Chao
2014-01-01
Access control is a key technology in providing security in the Internet of Things (IoT). The mainstream security approach proposed for the sensing layer of the IoT concentrates only on authentication while ignoring the more general models. Unreliable communications and resource constraints make the traditional access control techniques barely meet the requirements of the sensing layer of the IoT. In this paper, we propose a model that combines space and time with reputation to control access to the information within the sensing layer of the IoT. This model is called spatiotemporal access control based on reputation (STRAC). STRAC uses a lattice-based approach to decrease the size of policy bases. To solve the problem caused by unreliable communications, we propose both nondeterministic authorizations and stochastic authorizations. To more precisely manage the reputation of nodes, we propose two new mechanisms to update the reputation of nodes. These new approaches are the authority-based update mechanism (AUM) and the election-based update mechanism (EUM). We show how the model checker UPPAAL can be used to analyze the spatiotemporal access control model of an application. Finally, we also implement a prototype system to demonstrate the efficiency of our model. PMID:25177731
Kim, Seungjoo
2014-01-01
There has been an explosive increase in the population of the OSN (online social network) in recent years. The OSN provides users with many opportunities to communicate among friends and family. Further, it facilitates developing new relationships with previously unknown people having similar beliefs or interests. However, the OSN can expose users to adverse effects such as privacy breaches, the disclosing of uncontrolled material, and the disseminating of false information. Traditional access control models such as MAC, DAC, and RBAC are applied to the OSN to address these problems. However, these models are not suitable for the dynamic OSN environment because user behavior in the OSN is unpredictable and static access control imposes a burden on the users to change the access control rules individually. We propose a dynamic trust-based access control for the OSN to address the problems of the traditional static access control. Moreover, we provide novel criteria to evaluate trust factors such as sociological approach and evaluate a method to calculate the dynamic trust values. The proposed method can monitor negative behavior and modify access permission levels dynamically to prevent the indiscriminate disclosure of information. PMID:25374943
Baek, Seungsoo; Kim, Seungjoo
2014-01-01
There has been an explosive increase in the population of the OSN (online social network) in recent years. The OSN provides users with many opportunities to communicate among friends and family. Further, it facilitates developing new relationships with previously unknown people having similar beliefs or interests. However, the OSN can expose users to adverse effects such as privacy breaches, the disclosing of uncontrolled material, and the disseminating of false information. Traditional access control models such as MAC, DAC, and RBAC are applied to the OSN to address these problems. However, these models are not suitable for the dynamic OSN environment because user behavior in the OSN is unpredictable and static access control imposes a burden on the users to change the access control rules individually. We propose a dynamic trust-based access control for the OSN to address the problems of the traditional static access control. Moreover, we provide novel criteria to evaluate trust factors such as sociological approach and evaluate a method to calculate the dynamic trust values. The proposed method can monitor negative behavior and modify access permission levels dynamically to prevent the indiscriminate disclosure of information.
A dynamic access control method based on QoS requirement
NASA Astrophysics Data System (ADS)
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.
An Attribute Based Access Control Framework for Healthcare System
NASA Astrophysics Data System (ADS)
Afshar, Majid; Samet, Saeed; Hu, Ting
2018-01-01
Nowadays, access control is an indispensable part of the Personal Health Record and supplies for its confidentiality by enforcing policies and rules to ensure that only authorized users gain access to requested resources in the system. In other words, the access control means protecting patient privacy in healthcare systems. Attribute-Based Access Control (ABAC) is a new access control model that can be used instead of other traditional types of access control such as Discretionary Access Control, Mandatory Access Control, and Role-Based Access Control. During last five years ABAC has shown some applications in both recent academic fields and industry purposes. ABAC by using user’s attributes and resources, makes a decision according to an access request. In this paper, we propose an ABAC framework for healthcare system. We use the engine of ABAC for rendering and enforcing healthcare policies. Moreover, we handle emergency situations in this framework.
A Novel Reference Security Model with the Situation Based Access Policy for Accessing EPHR Data.
Gope, Prosanta; Amin, Ruhul
2016-11-01
Electronic Patient Health Record (EPHR) systems may facilitate a patient not only to share his/her health records securely with healthcare professional but also to control his/her health privacy, in a convenient and easy way even in case of emergency. In order to fulfill these requirements, it is greatly desirable to have the access control mechanism which can efficiently handle every circumstance without negotiating security. However, the existing access control mechanisms used in healthcare to regulate and restrict the disclosure of patient data are often bypassed in case of emergencies. In this article, we propose a way to securely share EPHR data under any situation including break-the-glass (BtG) without compromising its security. In this regard, we design a reference security model, which consists of a multi-level data flow hierarchy, and an efficient access control framework based on the conventional Role-Based Access Control (RBAC) and Mandatory Access Control (MAC) policies.
Feasibility Assessment of a Fine-Grained Access Control Model on Resource Constrained Sensors.
Uriarte Itzazelaia, Mikel; Astorga, Jasone; Jacob, Eduardo; Huarte, Maider; Romaña, Pedro
2018-02-13
Upcoming smart scenarios enabled by the Internet of Things (IoT) envision smart objects that provide services that can adapt to user behavior or be managed to achieve greater productivity. In such environments, smart things are inexpensive and, therefore, constrained devices. However, they are also critical components because of the importance of the information that they provide. Given this, strong security is a requirement, but not all security mechanisms in general and access control models in particular are feasible. In this paper, we present the feasibility assessment of an access control model that utilizes a hybrid architecture and a policy language that provides dynamic fine-grained policy enforcement in the sensors, which requires an efficient message exchange protocol called Hidra. This experimental performance assessment includes a prototype implementation, a performance evaluation model, the measurements and related discussions, which demonstrate the feasibility and adequacy of the analyzed access control model.
Feasibility Assessment of a Fine-Grained Access Control Model on Resource Constrained Sensors
Huarte, Maider; Romaña, Pedro
2018-01-01
Upcoming smart scenarios enabled by the Internet of Things (IoT) envision smart objects that provide services that can adapt to user behavior or be managed to achieve greater productivity. In such environments, smart things are inexpensive and, therefore, constrained devices. However, they are also critical components because of the importance of the information that they provide. Given this, strong security is a requirement, but not all security mechanisms in general and access control models in particular are feasible. In this paper, we present the feasibility assessment of an access control model that utilizes a hybrid architecture and a policy language that provides dynamic fine-grained policy enforcement in the sensors, which requires an efficient message exchange protocol called Hidra. This experimental performance assessment includes a prototype implementation, a performance evaluation model, the measurements and related discussions, which demonstrate the feasibility and adequacy of the analyzed access control model. PMID:29438338
An access control model with high security for distributed workflow and real-time application
NASA Astrophysics Data System (ADS)
Han, Ruo-Fei; Wang, Hou-Xiang
2007-11-01
The traditional mandatory access control policy (MAC) is regarded as a policy with strict regulation and poor flexibility. The security policy of MAC is so compelling that few information systems would adopt it at the cost of facility, except some particular cases with high security requirement as military or government application. However, with the increasing requirement for flexibility, even some access control systems in military application have switched to role-based access control (RBAC) which is well known as flexible. Though RBAC can meet the demands for flexibility but it is weak in dynamic authorization and consequently can not fit well in the workflow management systems. The task-role-based access control (T-RBAC) is then introduced to solve the problem. It combines both the advantages of RBAC and task-based access control (TBAC) which uses task to manage permissions dynamically. To satisfy the requirement of system which is distributed, well defined with workflow process and critically for time accuracy, this paper will analyze the spirit of MAC, introduce it into the improved T&RBAC model which is based on T-RBAC. At last, a conceptual task-role-based access control model with high security for distributed workflow and real-time application (A_T&RBAC) is built, and its performance is simply analyzed.
Cruz-Piris, Luis; Rivera, Diego; Marsa-Maestre, Ivan; de la Hoz, Enrique; Velasco, Juan R
2018-03-20
Internet growth has generated new types of services where the use of sensors and actuators is especially remarkable. These services compose what is known as the Internet of Things (IoT). One of the biggest current challenges is obtaining a safe and easy access control scheme for the data managed in these services. We propose integrating IoT devices in an access control system designed for Web-based services by modelling certain IoT communication elements as resources. This would allow us to obtain a unified access control scheme between heterogeneous devices (IoT devices, Internet-based services, etc.). To achieve this, we have analysed the most relevant communication protocols for these kinds of environments and then we have proposed a methodology which allows the modelling of communication actions as resources. Then, we can protect these resources using access control mechanisms. The validation of our proposal has been carried out by selecting a communication protocol based on message exchange, specifically Message Queuing Telemetry Transport (MQTT). As an access control scheme, we have selected User-Managed Access (UMA), an existing Open Authorization (OAuth) 2.0 profile originally developed for the protection of Internet services. We have performed tests focused on validating the proposed solution in terms of the correctness of the access control system. Finally, we have evaluated the energy consumption overhead when using our proposal.
2018-01-01
Internet growth has generated new types of services where the use of sensors and actuators is especially remarkable. These services compose what is known as the Internet of Things (IoT). One of the biggest current challenges is obtaining a safe and easy access control scheme for the data managed in these services. We propose integrating IoT devices in an access control system designed for Web-based services by modelling certain IoT communication elements as resources. This would allow us to obtain a unified access control scheme between heterogeneous devices (IoT devices, Internet-based services, etc.). To achieve this, we have analysed the most relevant communication protocols for these kinds of environments and then we have proposed a methodology which allows the modelling of communication actions as resources. Then, we can protect these resources using access control mechanisms. The validation of our proposal has been carried out by selecting a communication protocol based on message exchange, specifically Message Queuing Telemetry Transport (MQTT). As an access control scheme, we have selected User-Managed Access (UMA), an existing Open Authorization (OAuth) 2.0 profile originally developed for the protection of Internet services. We have performed tests focused on validating the proposed solution in terms of the correctness of the access control system. Finally, we have evaluated the energy consumption overhead when using our proposal. PMID:29558406
Information-Flow-Based Access Control for Web Browsers
NASA Astrophysics Data System (ADS)
Yoshihama, Sachiko; Tateishi, Takaaki; Tabuchi, Naoshi; Matsumoto, Tsutomu
The emergence of Web 2.0 technologies such as Ajax and Mashup has revealed the weakness of the same-origin policy[1], the current de facto standard for the Web browser security model. We propose a new browser security model to allow fine-grained access control in the client-side Web applications for secure mashup and user-generated contents. We propose a browser security model that is based on information-flow-based access control (IBAC) to overcome the dynamic nature of the client-side Web applications and to accurately determine the privilege of scripts in the event-driven programming model.
An Action-Based Fine-Grained Access Control Mechanism for Structured Documents and Its Application
Su, Mang; Li, Fenghua; Tang, Zhi; Yu, Yinyan; Zhou, Bo
2014-01-01
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. PMID:25136651
An action-based fine-grained access control mechanism for structured documents and its application.
Su, Mang; Li, Fenghua; Tang, Zhi; Yu, Yinyan; Zhou, Bo
2014-01-01
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.
A contextual role-based access control authorization model for electronic patient record.
Motta, Gustavo H M B; Furuie, Sergio S
2003-09-01
The design of proper models for authorization and access control for electronic patient record (EPR) is essential to a wide scale use of EPR in large health organizations. In this paper, we propose a contextual role-based access control authorization model aiming to increase the patient privacy and the confidentiality of patient data, whereas being flexible enough to consider specific cases. This model regulates user's access to EPR based on organizational roles. It supports a role-tree hierarchy with authorization inheritance; positive and negative authorizations; static and dynamic separation of duties based on weak and strong role conflicts. Contextual authorizations use environmental information available at access time, like user/patient relationship, in order to decide whether a user is allowed to access an EPR resource. This enables the specification of a more flexible and precise authorization policy, where permission is granted or denied according to the right and the need of the user to carry out a particular job function.
REVIEW: Widespread access to predictive models in the motor system: a short review
NASA Astrophysics Data System (ADS)
Davidson, Paul R.; Wolpert, Daniel M.
2005-09-01
Recent behavioural and computational studies suggest that access to internal predictive models of arm and object dynamics is widespread in the sensorimotor system. Several systems, including those responsible for oculomotor and skeletomotor control, perceptual processing, postural control and mental imagery, are able to access predictions of the motion of the arm. A capacity to make and use predictions of object dynamics is similarly widespread. Here, we review recent studies looking at the predictive capacity of the central nervous system which reveal pervasive access to forward models of the environment.
Research on a dynamic workflow access control model
NASA Astrophysics Data System (ADS)
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.
A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems
Choi, Donghee; Kim, Dohoon; Park, Seog
2015-01-01
Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment. PMID:26075013
An Integrated Model of Cognitive Control in Task Switching
ERIC Educational Resources Information Center
Altmann, Erik M.; Gray, Wayne D.
2008-01-01
A model of cognitive control in task switching is developed in which controlled performance depends on the system maintaining access to a code in episodic memory representing the most recently cued task. The main constraint on access to the current task code is proactive interference from old task codes. This interference and the mechanisms that…
Developing Access Control Model of Web OLAP over Trusted and Collaborative Data Warehouses
NASA Astrophysics Data System (ADS)
Fugkeaw, Somchart; Mitrpanont, Jarernsri L.; Manpanpanich, Piyawit; Juntapremjitt, Sekpon
This paper proposes the design and development of Role- based Access Control (RBAC) model for the Single Sign-On (SSO) Web-OLAP query spanning over multiple data warehouses (DWs). The model is based on PKI Authentication and Privilege Management Infrastructure (PMI); it presents a binding model of RBAC authorization based on dimension privilege specified in attribute certificate (AC) and user identification. Particularly, the way of attribute mapping between DW user authentication and privilege of dimensional access is illustrated. In our approach, we apply the multi-agent system to automate flexible and effective management of user authentication, role delegation as well as system accountability. Finally, the paper culminates in the prototype system A-COLD (Access Control of web-OLAP over multiple DWs) that incorporates the OLAP features and authentication and authorization enforcement in the multi-user and multi-data warehouse environment.
Secure access control and large scale robust representation for online multimedia event detection.
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.
NASA Astrophysics Data System (ADS)
Abramov, G. V.; Emeljanov, A. E.; Ivashin, A. L.
Theoretical bases for modeling a digital control system with information transfer via the channel of plural access and a regular quantization cycle are submitted. The theory of dynamic systems with random changes of the structure including elements of the Markov random processes theory is used for a mathematical description of a network control system. The characteristics of similar control systems are received. Experimental research of the given control systems is carried out.
The Role of Automatic Indexing in Access Control: A Modular View
ERIC Educational Resources Information Center
Hartson, H. Rex
1974-01-01
A model which relates the access control and indexing functions. The model is based on concept protection which allows a practically unbounded number of levels (subsets) of protection without requiring a fixed hierarchy among the levels. This protection is offered independently for each of the user operations allowed. (Author)
2015-03-01
a hotel and a hospital. 2. Event handler for emergency policies (item 2 above): this has been implemented in two UG projects, one project developed a...Workshop on Logical and Se- mantic Frameworks, with Applications, Brasilia, Brazil , September 2014. Electronic Notes in Theoretical Computer Science (to...Brasilia, Brazil , September 2014, 2015. [3] S. Barker. The next 700 access control models or a unifying meta-model? In SACMAT 2009, 14th ACM Symposium on
Secure Access Control and Large Scale Robust Representation for Online Multimedia Event Detection
Liu, Changyu; 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. PMID:25147840
Urban search mobile platform modeling in hindered access conditions
NASA Astrophysics Data System (ADS)
Barankova, I. I.; Mikhailova, U. V.; Kalugina, O. B.; Barankov, V. V.
2018-05-01
The article explores the control system simulation and the design of the experimental model of the rescue robot mobile platform. The functional interface, a structural functional diagram of the mobile platform control unit, and a functional control scheme for the mobile platform of secure robot were modeled. The task of design a mobile platform for urban searching in hindered access conditions is realized through the use of a mechanical basis with a chassis and crawler drive, a warning device, human heat sensors and a microcontroller based on Arduino platforms.
Design of Accelerator Online Simulator Server Using Structured Data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, Guobao; /Brookhaven; Chu, Chungming
2012-07-06
Model based control plays an important role for a modern accelerator during beam commissioning, beam study, and even daily operation. With a realistic model, beam behaviour can be predicted and therefore effectively controlled. The approach used by most current high level application environments is to use a built-in simulation engine and feed a realistic model into that simulation engine. Instead of this traditional monolithic structure, a new approach using a client-server architecture is under development. An on-line simulator server is accessed via network accessible structured data. With this approach, a user can easily access multiple simulation codes. This paper describesmore » the design, implementation, and current status of PVData, which defines the structured data, and PVAccess, which provides network access to the structured data.« less
[Public control and equity of access to hospitals under non-State public administration].
Carneiro Junior, Nivaldo; Elias, Paulo Eduardo
2006-10-01
To analyze social health organizations in the light of public control and the guarantee of equity of access to health services. Utilizing the case study technique, two social health organizations in the metropolitan region of São Paulo were selected. The analytical categories were equity of access and public control, and these were based on interviews with key informants and technical-administrative reports. It was observed that the overall funding and administrative control of the social health organizations are functions of the state administrator. The presence of a local administrator is important for ensuring equity of access. Public control is expressed through supervisory actions, by means of accounting and financial procedures. Equity of access and public control are not taken into consideration in the administration of these organizations. The central question lies in the capacity of the public authorities to have a presence in implementing this model at the local level, thereby ensuring equity of access and taking public control into consideration.
Propulsive Reaction Control System Model
NASA Technical Reports Server (NTRS)
Brugarolas, Paul; Phan, Linh H.; Serricchio, Frederick; San Martin, Alejandro M.
2011-01-01
This software models a propulsive reaction control system (RCS) for guidance, navigation, and control simulation purposes. The model includes the drive electronics, the electromechanical valve dynamics, the combustion dynamics, and thrust. This innovation follows the Mars Science Laboratory entry reaction control system design, and has been created to meet the Mars Science Laboratory (MSL) entry, descent, and landing simulation needs. It has been built to be plug-and-play on multiple MSL testbeds [analysis, Monte Carlo, flight software development, hardware-in-the-loop, and ATLO (assembly, test and launch operations) testbeds]. This RCS model is a C language program. It contains two main functions: the RCS electronics model function that models the RCS FPGA (field-programmable-gate-array) processing and commanding of the RCS valve, and the RCS dynamic model function that models the valve and combustion dynamics. In addition, this software provides support functions to initialize the model states, set parameters, access model telemetry, and access calculated thruster forces.
Access Control for Cooperation Systems Based on Group Situation
NASA Astrophysics Data System (ADS)
Kim, Minsoo; Joshi, James B. D.; Kim, Minkoo
Cooperation systems characterize many emerging environments such as ubiquitous and pervasive systems. Agent based cooperation systems have been proposed in the literature to address challenges of such emerging application environments. A key aspect of such agent based cooperation system is the group situation that changes dynamically and governs the requirements of the cooperation. While individual agent context is important, the overall cooperation behavior is more driven by the group context because of relationships and interactions between agents. Dynamic access control based on group situation is a crucial challenge in such cooperation systems. In this paper we propose a dynamic role based access control model for cooperation systems based on group situation. The model emphasizes capability based agent to role mapping and group situation based permission assignment to allow capturing dynamic access policies that evolve continuously.
Canonical formalism for modelling and control of rigid body dynamics.
Gurfil, P
2005-12-01
This paper develops a new paradigm for stabilization of rigid-body dynamics. The state-space model is formulated using canonical elements, known as the Serret-Andoyer (SA) variables, thus far scarcely used for engineering applications. The main feature of the SA formalism is the reduction of the dynamics via the underlying symmetry stemming from conservation of angular momentum and rotational kinetic energy. The controllability of the system model is examined using the notion of accessibility, and is shown to be accessible from all points. Based on the accessibility proof, two nonlinear asymptotic feedback stabilizers are developed: a damping feedback is designed based on the Jurdjevic-Quinn method, and a Hamiltonian controller is derived by using the Hamiltonian as a natural Lyapunov function for the closed-loop dynamics. It is shown that the Hamiltonian control is both passive and inverse optimal with respect to a meaningful performance index. The performance of the new controllers is examined and compared using simulations of realistic scenarios from the satellite attitude dynamics field.
Microcomputer Applications with PC LAN (Local Area Network) in Battleships.
1988-12-01
NETWORKS 5 C. TRANSMISSION TECHNIQUES 6 D. MEDIUM ACCESS CONTROL METHODS 6 1. CSMA CD 6 2. Control Token 7 3. Slotted Ring 7 E...network model in the Turkish Battleships will employ the broadband technique. D. MEDIUM ACCESS CONTROL METHODS The access method is one of the most...better performance at heavier loads. 3. Slotted Ring This method is used with a ring network. The ring is initialized to contain a fixed number of
Authenticated IGMP for Controlling Access to Multicast Distribution Tree
NASA Astrophysics Data System (ADS)
Park, Chang-Seop; Kang, Hyun-Sun
A receiver access control scheme is proposed to protect the multicast distribution tree from DoS attack induced by unauthorized use of IGMP, by extending the security-related functionality of IGMP. Based on a specific network and business model adopted for commercial deployment of IP multicast applications, a key management scheme is also presented for bootstrapping the proposed access control as well as accounting and billing for CP (Content Provider), NSP (Network Service Provider), and group members.
Security for safety critical space borne systems
NASA Technical Reports Server (NTRS)
Legrand, Sue
1987-01-01
The Space Station contains safety critical computer software components in systems that can affect life and vital property. These components require a multilevel secure system that provides dynamic access control of the data and processes involved. A study is under way to define requirements for a security model providing access control through level B3 of the Orange Book. The model will be prototyped at NASA-Johnson Space Center.
Proximity-based access control for context-sensitive information provision in SOA-based systems
NASA Astrophysics Data System (ADS)
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.
Empowering citizens with access control mechanisms to their personal health resources.
Calvillo, J; Román, I; Roa, L M
2013-01-01
Advancements in information and communication technologies have allowed the development of new approaches to the management and use of healthcare resources. Nowadays it is possible to address complex issues such as meaningful access to distributed data or communication and understanding among heterogeneous systems. As a consequence, the discussion focuses on the administration of the whole set of resources providing knowledge about a single subject of care (SoC). New trends make the SoC administrator and responsible for all these elements (related to his/her demographic data, health, well-being, social conditions, etc.) and s/he is granted the ability of controlling access to them by third parties. The subject of care exchanges his/her passive role without any decision capacity for an active one allowing to control who accesses what. We study the necessary access control infrastructure to support this approach and develop mechanisms based on semantic tools to assist the subject of care with the specification of access control policies. This infrastructure is a building block of a wider scenario, the Person-Oriented Virtual Organization (POVO), aiming at integrating all the resources related to each citizen's health-related data. The POVO covers the wide range and heterogeneity of available healthcare resources (e.g., information sources, monitoring devices, or software simulation tools) and grants each SoC the access control to them. Several methodological issues are crucial for the design of the targeted infrastructure. The distributed system concept and focus are reviewed from the service oriented architecture (SOA) perspective. The main frameworks for the formalization of distributed system architectures (Reference Model-Open Distributed Processing, RM-ODP; and Model Driven Architecture, MDA) are introduced, as well as how the use of the Unified Modelling Language (UML) is standardized. The specification of access control policies and decision making mechanisms are essential keys for this approach and they are accomplished by using semantic technologies (i.e., ontologies, rule languages, and inference engines). The results are mainly focused on the security and access control of the proposed scenario. An ontology has been designed and developed for the POVO covering the terminology of the scenario and easing the automation of administration tasks. Over that ontology, an access control mechanism based on rule languages allows specifying access control policies, and an inference engine performs the decision making process automatically. The usability of solutions to ease administration tasks to the SoC is improved by the Me-As-An-Admin (M3A) application. This guides the SoC through the specification of personal access control policies to his/her distributed resources by using semantic technologies (e.g., metamodeling, model-to-text transformations, etc.). All results are developed as services and included in an architecture in accordance with standards and principles of openness and interoperability. Current technology can bring health, social and well-being care actually centered on citizens, and granting each person the management of his/her health information. However, the application of technology without adopting methodologies or normalized guidelines will reduce the interoperability of solutions developed, failing in the development of advanced services and improved scenarios for health delivery. Standards and reference architectures can be cornerstones for future-proof and powerful developments. Finally, not only technology must follow citizen-centric approaches, but also the gaps needing legislative efforts that support these new paradigms of healthcare delivery must be identified and addressed. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Framework and prototype for a secure XML-based electronic health records system.
Steele, Robert; Gardner, William; Chandra, Darius; Dillon, Tharam S
2007-01-01
Security of personal medical information has always been a challenge for the advancement of Electronic Health Records (EHRs) initiatives. eXtensible Markup Language (XML), is rapidly becoming the key standard for data representation and transportation. The widespread use of XML and the prospect of its use in the Electronic Health (e-health) domain highlights the need for flexible access control models for XML data and documents. This paper presents a declarative access control model for XML data repositories that utilises an expressive XML role control model. The operational semantics of this model are illustrated by Xplorer, a user interface generation engine which supports search-browse-navigate activities on XML repositories.
Fleischer, Nancy L; Thrasher, James F; Reynales-Shigematsu, Luz Myriam; Cummings, K Michael; Meza, Rafael; Zhang, Yian; Levy, David T
2017-07-01
We examined the effect of tobacco control policies in Mexico on smoking prevalence and smoking-related deaths using the Mexico SimSmoke model. The model is based on the previously developed SimSmoke simulation model of tobacco control policy, and uses population size, smoking rates and tobacco control policy data for Mexico. It assesses, individually, and in combination, the effect of six tobacco control policies on smoking prevalence and smoking-related deaths. Policies included: cigarette excise taxes, smoke-free laws, anti-smoking public education campaigns, marketing restrictions, access to tobacco cessation treatments and enforcement against tobacco sales youth. The model estimates that, if Mexico were to adopt strong tobacco control policies compared to current policy levels, smoking prevalence could be reduced by 30% in the next decade and by 50% by 2053; an additional 470,000 smoking-related premature deaths could be averted over the next 40 years. The greatest impact on smoking and smoking-related deaths would be achieved by raising excise taxes on cigarettes from 55% to at least 70% of the retail price, followed by strong youth access enforcement and access to cessation treatments. Implementing tobacco control policies in Mexico could reduce smoking prevalence by 50%, and prevent 470,000 smoking-related deaths by 2053.
ERIC Educational Resources Information Center
Iowa State Dept. of Public Instruction, Des Moines.
This model policy is designed to help local school officials provide vendors with the greatest reasonable opportunity to compete for access to the school community, while protecting the school's need for reasonable control of that access, so that students, parents, and staff can obtain the best goods and services at the best price. It is offered…
Lin, Yun; Wang, Chao; Wang, Jiaxing; Dou, Zheng
2016-10-12
Cognitive radio sensor networks are one of the kinds of application where cognitive techniques can be adopted and have many potential applications, challenges and future research trends. According to the research surveys, dynamic spectrum access is an important and necessary technology for future cognitive sensor networks. Traditional methods of dynamic spectrum access are based on spectrum holes and they have some drawbacks, such as low accessibility and high interruptibility, which negatively affect the transmission performance of the sensor networks. To address this problem, in this paper a new initialization mechanism is proposed to establish a communication link and set up a sensor network without adopting spectrum holes to convey control information. Specifically, firstly a transmission channel model for analyzing the maximum accessible capacity for three different polices in a fading environment is discussed. Secondly, a hybrid spectrum access algorithm based on a reinforcement learning model is proposed for the power allocation problem of both the transmission channel and the control channel. Finally, extensive simulations have been conducted and simulation results show that this new algorithm provides a significant improvement in terms of the tradeoff between the control channel reliability and the efficiency of the transmission channel.
Lin, Yun; Wang, Chao; Wang, Jiaxing; Dou, Zheng
2016-01-01
Cognitive radio sensor networks are one of the kinds of application where cognitive techniques can be adopted and have many potential applications, challenges and future research trends. According to the research surveys, dynamic spectrum access is an important and necessary technology for future cognitive sensor networks. Traditional methods of dynamic spectrum access are based on spectrum holes and they have some drawbacks, such as low accessibility and high interruptibility, which negatively affect the transmission performance of the sensor networks. To address this problem, in this paper a new initialization mechanism is proposed to establish a communication link and set up a sensor network without adopting spectrum holes to convey control information. Specifically, firstly a transmission channel model for analyzing the maximum accessible capacity for three different polices in a fading environment is discussed. Secondly, a hybrid spectrum access algorithm based on a reinforcement learning model is proposed for the power allocation problem of both the transmission channel and the control channel. Finally, extensive simulations have been conducted and simulation results show that this new algorithm provides a significant improvement in terms of the tradeoff between the control channel reliability and the efficiency of the transmission channel. PMID:27754316
Accessibility, stabilizability, and feedback control of continuous orbital transfer.
Gurfil, Pini
2004-05-01
This paper investigates the problem of low-thrust orbital transfer using orbital element feedback from a control-theoretic standpoint, concepts of controllability, feedback stabilizability, and their interaction. The Gauss variational equations (GVEs) are used to model the state-space dynamics. First, the notion of accessibility, a weaker form of controllability, is presented. It is then shown that the GVEs are globally accessible. Based on the accessibility result, a nonlinear feedback controller is derived that asymptotically steers a vehicle from an initial elliptic Keplerian orbit to any given elliptic Keplerian orbit. The performance of the new controller is illustrated by simulating an orbital transfer between two geosynchronous Earth orbits. It is shown that the low-thrust controller requires less fuel than an impulsive maneuver for the same transfer time. Closed-form, analytic expressions for the new orbital transfer controller are given. Finally, it is proved, based on a topological nonlinear stabilizability test, that there does not exist a continuous closed-loop controller that can transfer a spacecraft to a parabolic escape trajectory.
Access Control Management for SCADA Systems
NASA Astrophysics Data System (ADS)
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.
A slotted access control protocol for metropolitan WDM ring networks
NASA Astrophysics Data System (ADS)
Baziana, P. A.; Pountourakis, I. E.
2009-03-01
In this study we focus on the serious scalability problems that many access protocols for WDM ring networks introduce due to the use of a dedicated wavelength per access node for either transmission or reception. We propose an efficient slotted MAC protocol suitable for WDM ring metropolitan area networks. The proposed network architecture employs a separate wavelength for control information exchange prior to the data packet transmission. Each access node is equipped with a pair of tunable transceivers for data communication and a pair of fixed tuned transceivers for control information exchange. Also, each access node includes a set of fixed delay lines for synchronization reasons; to keep the data packets, while the control information is processed. An efficient access algorithm is applied to avoid both the data wavelengths and the receiver collisions. In our protocol, each access node is capable of transmitting and receiving over any of the data wavelengths, facing the scalability issues. Two different slot reuse schemes are assumed: the source and the destination stripping schemes. For both schemes, performance measures evaluation is provided via an analytic model. The analytical results are validated by a discrete event simulation model that uses Poisson traffic sources. Simulation results show that the proposed protocol manages efficient bandwidth utilization, especially under high load. Also, comparative simulation results prove that our protocol achieves significant performance improvement as compared with other WDMA protocols which restrict transmission over a dedicated data wavelength. Finally, performance measures evaluation is explored for diverse numbers of buffer size, access nodes and data wavelengths.
Sujansky, Walter V; Faus, Sam A; Stone, Ethan; Brennan, Patricia Flatley
2010-10-01
Online personal health records (PHRs) enable patients to access, manage, and share certain of their own health information electronically. This capability creates the need for precise access-controls mechanisms that restrict the sharing of data to that intended by the patient. The authors describe the design and implementation of an access-control mechanism for PHR repositories that is modeled on the eXtensible Access Control Markup Language (XACML) standard, but intended to reduce the cognitive and computational complexity of XACML. The authors implemented the mechanism entirely in a relational database system using ANSI-standard SQL statements. Based on a set of access-control rules encoded as relational table rows, the mechanism determines via a single SQL query whether a user who accesses patient data from a specific application is authorized to perform a requested operation on a specified data object. Testing of this query on a moderately large database has demonstrated execution times consistently below 100ms. The authors include the details of the implementation, including algorithms, examples, and a test database as Supplementary materials. Copyright © 2010 Elsevier Inc. All rights reserved.
Mandatory and Location-Aware Access Control for Relational Databases
NASA Astrophysics Data System (ADS)
Decker, Michael
Access control is concerned with determining which operations a particular user is allowed to perform on a particular electronic resource. For example, an access control decision could say that user Alice is allowed to perform the operation read (but not write) on the resource research report. With conventional access control this decision is based on the user's identity whereas the basic idea of Location-Aware Access Control (LAAC) is to evaluate also a user's current location when making the decision if a particular request should be granted or denied. LAAC is an interesting approach for mobile information systems because these systems are exposed to specific security threads like the loss of a device. Some data models for LAAC can be found in literature, but almost all of them are based on RBAC and none of them is designed especially for Database Management Systems (DBMS). In this paper we therefore propose a LAAC-approach for DMBS and describe a prototypical implementation of that approach that is based on database triggers.
Hormone-dependent control of developmental timing through regulation of chromatin accessibility
Uyehara, Christopher M.; Nystrom, Spencer L.; Niederhuber, Matthew J.; Leatham-Jensen, Mary; Ma, Yiqin; Buttitta, Laura A.
2017-01-01
Specification of tissue identity during development requires precise coordination of gene expression in both space and time. Spatially, master regulatory transcription factors are required to control tissue-specific gene expression programs. However, the mechanisms controlling how tissue-specific gene expression changes over time are less well understood. Here, we show that hormone-induced transcription factors control temporal gene expression by regulating the accessibility of DNA regulatory elements. Using the Drosophila wing, we demonstrate that temporal changes in gene expression are accompanied by genome-wide changes in chromatin accessibility at temporal-specific enhancers. We also uncover a temporal cascade of transcription factors following a pulse of the steroid hormone ecdysone such that different times in wing development can be defined by distinct combinations of hormone-induced transcription factors. Finally, we show that the ecdysone-induced transcription factor E93 controls temporal identity by directly regulating chromatin accessibility across the genome. Notably, we found that E93 controls enhancer activity through three different modalities, including promoting accessibility of late-acting enhancers and decreasing accessibility of early-acting enhancers. Together, this work supports a model in which an extrinsic signal triggers an intrinsic transcription factor cascade that drives development forward in time through regulation of chromatin accessibility. PMID:28536147
A game-theoretical approach to multimedia social networks security.
Liu, Enqiang; Liu, Zengliang; Shao, Fei; Zhang, Zhiyong
2014-01-01
The contents access and sharing in multimedia social networks (MSNs) mainly rely on access control models and mechanisms. Simple adoptions of security policies in the traditional access control model cannot effectively establish a trust relationship among parties. This paper proposed a novel two-party trust architecture (TPTA) to apply in a generic MSN scenario. According to the architecture, security policies are adopted through game-theoretic analyses and decisions. Based on formalized utilities of security policies and security rules, the choice of security policies in content access is described as a game between the content provider and the content requester. By the game method for the combination of security policies utility and its influences on each party's benefits, the Nash equilibrium is achieved, that is, an optimal and stable combination of security policies, to establish and enhance trust among stakeholders.
A Game-Theoretical Approach to Multimedia Social Networks Security
Liu, Enqiang; Liu, Zengliang; Shao, Fei; Zhang, Zhiyong
2014-01-01
The contents access and sharing in multimedia social networks (MSNs) mainly rely on access control models and mechanisms. Simple adoptions of security policies in the traditional access control model cannot effectively establish a trust relationship among parties. This paper proposed a novel two-party trust architecture (TPTA) to apply in a generic MSN scenario. According to the architecture, security policies are adopted through game-theoretic analyses and decisions. Based on formalized utilities of security policies and security rules, the choice of security policies in content access is described as a game between the content provider and the content requester. By the game method for the combination of security policies utility and its influences on each party's benefits, the Nash equilibrium is achieved, that is, an optimal and stable combination of security policies, to establish and enhance trust among stakeholders. PMID:24977226
Access Control Model for Sharing Composite Electronic Health Records
NASA Astrophysics Data System (ADS)
Jin, Jing; Ahn, Gail-Joon; Covington, Michael J.; Zhang, Xinwen
The adoption of electronically formatted medical records, so called Electronic Health Records (EHRs), has become extremely important in healthcare systems to enable the exchange of medical information among stakeholders. An EHR generally consists of data with different types and sensitivity degrees which must be selectively shared based on the need-to-know principle. Security mechanisms are required to guarantee that only authorized users have access to specific portions of such critical record for legitimate purposes. In this paper, we propose a novel approach for modelling access control scheme for composite EHRs. Our model formulates the semantics and structural composition of an EHR document, from which we introduce a notion of authorized zones of the composite EHR at different granularity levels, taking into consideration of several important criteria such as data types, intended purposes and information sensitivities.
Yi, Meng; Chen, Qingkui; Xiong, Neal N
2016-11-03
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.
Protection - Principles and practice.
NASA Technical Reports Server (NTRS)
Graham, G. S.; Denning, P. J.
1972-01-01
The protection mechanisms of computer systems control the access to objects, especially information objects. The principles of protection system design are formalized as a model (theory) of protection. Each process has a unique identification number which is attached by the system to each access attempted by the process. Details of system implementation are discussed, taking into account the storing of the access matrix, aspects of efficiency, and the selection of subjects and objects. Two systems which have protection features incorporating all the elements of the model are described.
Information Assurance and Cyber Defence (Assurance de l’information et cyberdefense)
2010-11-01
project is that knowledge exchange in a timely fashion is highly significant. Authentication and Authorisation of Users and Services in Federated...Detection, Protection and Countermeasures; • Security Models and Architectures; • Security Policies, Evaluation, Authorisation and Access Control; and...Evaluation, Authorisation and Access Control • Network and Information Security Awareness The topics for the symposium had been established
Securely and Flexibly Sharing a Biomedical Data Management System
Wang, Fusheng; Hussels, Phillip; Liu, Peiya
2011-01-01
Biomedical database systems need not only to address the issues of managing complex data, but also to provide data security and access control to the system. These include not only system level security, but also instance level access control such as access of documents, schemas, or aggregation of information. The latter is becoming more important as multiple users can share a single scientific data management system to conduct their research, while data have to be protected before they are published or IP-protected. This problem is challenging as users’ needs for data security vary dramatically from one application to another, in terms of who to share with, what resources to be shared, and at what access level. We develop a comprehensive data access framework for a biomedical data management system SciPort. SciPort provides fine-grained multi-level space based access control of resources at not only object level (documents and schemas), but also space level (resources set aggregated in a hierarchy way). Furthermore, to simplify the management of users and privileges, customizable role-based user model is developed. The access control is implemented efficiently by integrating access privileges into the backend XML database, thus efficient queries are supported. The secure access approach we take makes it possible for multiple users to share the same biomedical data management system with flexible access management and high data security. PMID:21625285
NASA Astrophysics Data System (ADS)
Hirono, Masahiko; Nojima, Toshio
This paper presents a new signaling architecture for radio-access control in wireless communications systems. Called THREP (for THREe-phase link set-up Process), it enables systems with low-cost configurations to provide tetherless access and wide-ranging mobility by using autonomous radio-link controls for fast cell searching and distributed call management. A signaling architecture generally consists of a radio-access part and a service-entity-access part. In THREP, the latter part is divided into two steps: preparing a communication channel, and sustaining it. Access control in THREP is thus composed of three separated parts, or protocol phases. The specifications of each phase are determined independently according to system requirements. In the proposed architecture, the first phase uses autonomous radio-link control because we want to construct low-power indoor wireless communications systems. Evaluation of channel usage efficiency and hand-over loss probability in the personal handy-phone system (PHS) shows that THREP makes the radio-access sub-system operations in a practical application model highly efficient, and the results of a field experiment show that THREP provides sufficient protection against severe fast CNR degradation in practical indoor propagation environments.
Modeling rural landowners' hunter access policies in East Texas, USA
NASA Astrophysics Data System (ADS)
Wright, Brett A.; Fesenmaier, Daniel R.
1988-03-01
Private landowners in East Texas, USA, were aggregated into one of four policy categories according to the degree of access allowed to their lands for hunting. Based on these categories, a logistic regression model of possible determinants of access policy was developed and probabilities of policy adoption were calculated. Overwhelmingly, attitudes toward hunting as a sport, incentives, and control over the actions of hunters were most predictive of landowners' policies. Additionally, the availability of deer was found to be negatively correlated with access, thereby suggesting management efforts to increase deer populations may be counter to increasing access. Further, probabilities derived from the model indicated that there was almost a 7 in 10 chance (0.66) that landowners would adopt policies commensurate with allowing family and personal acquaintances to hunt on their property. However, the probability of increasing access beyond this level, where access was provided for the general public, dropped off drastically to less than 5% (0.04).
SERVER DEVELOPMENT FOR NSLS-II PHYSICS APPLICATIONS AND PERFORMANCE ANALYSIS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, G.; Kraimer, M.
2011-03-28
The beam commissioning software framework of NSLS-II project adopts a client/server based architecture to replace the more traditional monolithic high level application approach. The server software under development is available via an open source sourceforge project named epics-pvdata, which consists of modules pvData, pvAccess, pvIOC, and pvService. Examples of two services that already exist in the pvService module are itemFinder, and gather. Each service uses pvData to store in-memory transient data, pvService to transfer data over the network, and pvIOC as the service engine. The performance benchmarking for pvAccess and both gather service and item finder service are presented inmore » this paper. The performance comparison between pvAccess and Channel Access are presented also. For an ultra low emittance synchrotron radiation light source like NSLS II, the control system requirements, especially for beam control are tight. To control and manipulate the beam effectively, a use case study has been performed to satisfy the requirement and theoretical evaluation has been performed. The analysis shows that model based control is indispensable for beam commissioning and routine operation. However, there are many challenges such as how to re-use a design model for on-line model based control, and how to combine the numerical methods for modeling of a realistic lattice with the analytical techniques for analysis of its properties. To satisfy the requirements and challenges, adequate system architecture for the software framework for beam commissioning and operation is critical. The existing traditional approaches are self-consistent, and monolithic. Some of them have adopted a concept of middle layer to separate low level hardware processing from numerical algorithm computing, physics modelling, data manipulating and plotting, and error handling. However, none of the existing approaches can satisfy the requirement. A new design has been proposed by introducing service oriented architecture technology, and client interface is undergoing. The design and implementation adopted a new EPICS implementation, namely epics-pvdata [9], which is under active development. The implementation of this project under Java is close to stable, and binding to other language such as C++ and/or Python is undergoing. In this paper, we focus on the performance benchmarking and comparison for pvAccess and Channel Access, the performance evaluation for 2 services, gather and item finder respectively.« less
Query Monitoring and Analysis for Database Privacy - A Security Automata Model Approach
Kumar, Anand; Ligatti, Jay; Tu, Yi-Cheng
2015-01-01
Privacy and usage restriction issues are important when valuable data are exchanged or acquired by different organizations. Standard access control mechanisms either restrict or completely grant access to valuable data. On the other hand, data obfuscation limits the overall usability and may result in loss of total value. There are no standard policy enforcement mechanisms for data acquired through mutual and copyright agreements. In practice, many different types of policies can be enforced in protecting data privacy. Hence there is the need for an unified framework that encapsulates multiple suites of policies to protect the data. We present our vision of an architecture named security automata model (SAM) to enforce privacy-preserving policies and usage restrictions. SAM analyzes the input queries and their outputs to enforce various policies, liberating data owners from the burden of monitoring data access. SAM allows administrators to specify various policies and enforces them to monitor queries and control the data access. Our goal is to address the problems of data usage control and protection through privacy policies that can be defined, enforced, and integrated with the existing access control mechanisms using SAM. In this paper, we lay out the theoretical foundation of SAM, which is based on an automata named Mandatory Result Automata. We also discuss the major challenges of implementing SAM in a real-world database environment as well as ideas to meet such challenges. PMID:26997936
Query Monitoring and Analysis for Database Privacy - A Security Automata Model Approach.
Kumar, Anand; Ligatti, Jay; Tu, Yi-Cheng
2015-11-01
Privacy and usage restriction issues are important when valuable data are exchanged or acquired by different organizations. Standard access control mechanisms either restrict or completely grant access to valuable data. On the other hand, data obfuscation limits the overall usability and may result in loss of total value. There are no standard policy enforcement mechanisms for data acquired through mutual and copyright agreements. In practice, many different types of policies can be enforced in protecting data privacy. Hence there is the need for an unified framework that encapsulates multiple suites of policies to protect the data. We present our vision of an architecture named security automata model (SAM) to enforce privacy-preserving policies and usage restrictions. SAM analyzes the input queries and their outputs to enforce various policies, liberating data owners from the burden of monitoring data access. SAM allows administrators to specify various policies and enforces them to monitor queries and control the data access. Our goal is to address the problems of data usage control and protection through privacy policies that can be defined, enforced, and integrated with the existing access control mechanisms using SAM. In this paper, we lay out the theoretical foundation of SAM, which is based on an automata named Mandatory Result Automata. We also discuss the major challenges of implementing SAM in a real-world database environment as well as ideas to meet such challenges.
Traffic Adaptive Energy Efficient and Low Latency Medium Access Control for Wireless Sensor Networks
NASA Astrophysics Data System (ADS)
Yadav, Rajesh; Varma, Shirshu; Malaviya, N.
2008-05-01
Medium access control for wireless sensor networks has been a very active research area in the recent years. The traditional wireless medium access control protocol such as IEEE 802.11 is not suitable for the sensor network application because these are battery powered. The recharging of these sensor nodes is expensive and also not possible. The most of the literature in the medium access for the sensor network focuses on the energy efficiency. The proposed MAC protocol solves the energy inefficiency caused by idle listening, control packet overhead and overhearing taking nodes latency into consideration based on the network traffic. Simulation experiments have been performed to demonstrate the effectiveness of the proposed approach. The validation of the simulation results of the proposed MAC has been done by comparing it with the analytical model. This protocol has been simulated in Network Simulator ns-2.
RBAC Driven Least Privilege Architecture For Control Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hull, Julie; Markham, Mark
The concept of role based access control (RBAC) within the IT environment has been studied by researchers and was supported by NIST (circa 1992). This earlier work highlighted the benefits of RBAC which include reduced administrative workload and policies which are easier to analyze and apply. The goals of this research were to expand the application of RBAC in the following ways. Apply RBAC to the control systems environment: The typical RBAC model within the IT environment is used to control a user’s access to files. Within the control system environment files are replaced with measurement (e.g., temperature) and controlmore » (e.g. valve) points organized as a hierarchy of control assets (e.g. a boiler, compressor, refinery unit). Control points have parameters (e.g., high alarm limit, set point, etc.) associated with them. The RBAC model is extended to support access to points and their parameters based upon roles while at the same time allowing permissions for the points to be defined at the asset level or point level directly. In addition, centralized policy administration with distributed access enforcement mechanisms was developed to support the distributed architecture of distributed control systems and SCADA; Extend the RBAC model to include access control for software and devices: The established RBAC approach is to assign users to roles. This work extends that notion by first breaking the control system down into three layers 1) users, 2) software and 3) devices. An RBAC model is then created for each of these three layers. The result is that RBAC can be used to define machine-to-machine policy enforced via the IP security (IPsec) protocol. This highlights the potential to use RBAC for machine-to-machine connectivity within the internet of things; and Enable dynamic policy based upon the operating mode of the system: The IT environment is generally static with respect to policy. However, large cyber physical systems such as industrial controls have various operating modes (start-up, normal operation, emergency, shut-down and maintenance are typical). The policy enforcement architecture must be able to support changes in access permissions as the mode of the control system changes. For example an operator’s role may not allow the operator to shut down a pump during “normal operation” but that same operator role may be given permission to shut down the pump if the refinery transitions to “emergency” mode. The effectiveness of the approach was validated by applying it to the Experion Process Knowledge System. This is a large commercial industrial control system often used to control oil refineries and other assets within the oil and gas sector. As a by-product, other industries using Experion (Pharmaceuticals, Specialty Chemicals, etc.) also benefit from increased security. Policies representative of those that would be used within an oil refinery were created and validated against the RBAC model as implemented in the underlying SQL database. The administration of policy is simplified which in turn makes it practical for security administrators to specify policies which enforce least privilege. The result is a qualitative reduction in risk. The benefits of the enhanced RBAC model are clear and as a result. Honeywell is incorporating portions of the RBAC research into the 2014 release of Experion.« less
Yi, Meng; Chen, Qingkui; Xiong, Neal N.
2016-01-01
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. PMID:27827878
Support Center for Regulatory Atmospheric Modeling (SCRAM)
This technical site provides access to air quality models (including computer code, input data, and model processors) and other mathematical simulation techniques used in assessing air emissions control strategies and source impacts.
A novel asynchronous access method with binary interfaces
2008-01-01
Background Traditionally synchronous access strategies require users to comply with one or more time constraints in order to communicate intent with a binary human-machine interface (e.g., mechanical, gestural or neural switches). Asynchronous access methods are preferable, but have not been used with binary interfaces in the control of devices that require more than two commands to be successfully operated. Methods We present the mathematical development and evaluation of a novel asynchronous access method that may be used to translate sporadic activations of binary interfaces into distinct outcomes for the control of devices requiring an arbitrary number of commands to be controlled. With this method, users are required to activate their interfaces only when the device under control behaves erroneously. Then, a recursive algorithm, incorporating contextual assumptions relevant to all possible outcomes, is used to obtain an informed estimate of user intention. We evaluate this method by simulating a control task requiring a series of target commands to be tracked by a model user. Results When compared to a random selection, the proposed asynchronous access method offers a significant reduction in the number of interface activations required from the user. Conclusion This novel access method offers a variety of advantages over traditionally synchronous access strategies and may be adapted to a wide variety of contexts, with primary relevance to applications involving direct object manipulation. PMID:18959797
A Model for Trust-based Access Control and Delegation in Mobile Clouds (Post Print)
2013-10-01
the access-granter knowing the identity of access requester beforehand and authenticating the requester, can no longer be applied. Mobile Wallet Cloud...TktC) for a reservation and con- tacts the user’s mobile wallet provider (MobWC) to purchase the ticket from TktC. For accessing different services...receiving regular services. For example, the human user in our scenario can be an elite member with the mobile wallet service provider that
Levy, David T; Bales, Sarah; Lam, Nguyen T; Nikolayev, Leonid
2006-04-01
A simulation model is developed for Vietnam to project smoking prevalence and associated premature mortality. The model examines independently and as a package the effects of five types of tobacco control policies: tax increases, clean air laws, mass media campaigns, advertising bans, and youth access policies. Predictions suggest that the largest reductions in smoking rates will result from implementing a comprehensive tobacco control policy package. Significant inroads may be achieved through tax increases. A media campaign along with programs to publicize and enforce clean air laws, advertising bans and youth access laws would further reduce smoking rates. Tobacco control policies have the potential to make large dents in smoking rates, which in turn could lead to many lives saved. In the absence of these measures, deaths from smoking will increase. The model also helps to identify information gaps pertinent both to modeling and policy-making.
Elliott, Mark A; Lee, Emme; Robertson, Jamie S; Innes, Rhona
2015-01-01
According to the MODE model of attitude-to-behavior processes, attitude accessibility augments attitude-behavior correspondence, reflecting an automatic influence of attitudes on behavior. We therefore tested whether attitude accessibility moderates the attitude-behavior relationship in a context that is governed by characteristically automatic behavior, namely driving. In study 1 (correlational design), participants (N=130) completed online questionnaire measures of the valences and accessibilities of their attitudes towards speeding. Two weeks later, online questionnaire measures of subsequent speeding behavior were obtained. Attitude valence was a significantly better predictor of behavior at high (mean+1SD) versus low (mean-1SD) levels of attitude accessibility. In study 2 (experimental design), attitude accessibility was manipulated with a repeated attitude expression task. Immediately after the manipulation, participants (N=122) completed online questionnaire measures of attitude valence and accessibility, and two weeks later, subsequent speeding behavior. Increased attitude accessibility in the experimental (versus control) condition generated an increase in attitude-behavior correspondence. The findings are consistent with the MODE model's proposition that attitudes can exert an automatic influence on behavior. Interventions to reduce speeding could usefully increase the accessibility of anti-speeding attitudes and reduce the accessibility of pro-speeding attitudes. Copyright © 2014 Elsevier Ltd. All rights reserved.
Security of medical multimedia.
Tzelepi, S; Pangalos, G; Nikolacopoulou, G
2002-09-01
The application of information technology to health care has generated growing concern about the privacy and security of medical information. Furthermore, data and communication security requirements in the field of multimedia are higher. In this paper we describe firstly the most important security requirements that must be fulfilled by multimedia medical data, and the security measures used to satisfy these requirements. These security measures are based mainly on modern cryptographic and watermarking mechanisms as well as on security infrastructures. The objective of our work is to complete this picture, exploiting the capabilities of multimedia medical data to define and implement an authorization model for regulating access to the data. In this paper we describe an extended role-based access control model by considering, within the specification of the role-permission relationship phase, the constraints that must be satisfied in order for the holders of the permission to use those permissions. The use of constraints allows role-based access control to be tailored to specifiy very fine-grained and flexible content-, context- and time-based access control policies. Other restrictions, such as role entry restriction also can be captured. Finally, the description of system architecture for a secure DBMS is presented.
Multiple memory stores and operant conditioning: a rationale for memory's complexity.
Meeter, Martijn; Veldkamp, Rob; Jin, Yaochu
2009-02-01
Why does the brain contain more than one memory system? Genetic algorithms can play a role in elucidating this question. Here, model animals were constructed containing a dorsal striatal layer that controlled actions, and a ventral striatal layer that controlled a dopaminergic learning signal. Both layers could gain access to three modeled memory stores, but such access was penalized as energy expenditure. Model animals were then selected on their fitness in simulated operant conditioning tasks. Results suggest that having access to multiple memory stores and their representations is important in learning to regulate dopamine release, as well as in contextual discrimination. For simple operant conditioning, as well as stimulus discrimination, hippocampal compound representations turned out to suffice, a counterintuitive result given findings that hippocampal lesions tend not to affect performance in such tasks. We argue that there is in fact evidence to support a role for compound representations and the hippocampus in even the simplest conditioning tasks.
A personally controlled electronic health record for Australia
Pearce, Christopher; Bainbridge, Michael
2014-01-01
Objective On July 1, 2012 Australia launched a personally controlled electronic health record (PCEHR) designed around the needs of consumers. Using a distributed model and leveraging key component national eHealth infrastructure, the PCEHR is designed to enable sharing of any health information about a patient with them and any other health practitioner involved in their care to whom the patient allows access. This paper discusses the consumer-facing part of the program. Method Design of the system was through stakeholder consultation and the development of detailed requirements, followed by clinical design assurance. Results Patients are able to access any posted information through a web-accessible ‘consumer portal.’ Within the portal they are able to assert access controls on all or part of their record. The portal includes areas for consumers to record their own personal information. Discussion The PCEHR has the potential to transform the ability of patients to actively engage in their own healthcare, and to enable the emerging partnership model of health and healthcare in medicine. The ability to access health information traditionally kept within the closed walls of institutions also raises challenges for the profession, both in the language clinicians choose and the ethical issues raised by the changed roles and responsibilities. Conclusions The PCEHR is aimed at connecting all participants and their interventions, and is intended to become a system-wide activity. PMID:24650635
University Access for Disadvantaged Children: A Comparison across Countries
ERIC Educational Resources Information Center
Jerrim, John; Vignoles, Anna
2015-01-01
In this paper, we consider whether certain countries are particularly adept (or particularly poor) at getting children from disadvantaged homes to study for a bachelor's degree. A series of university access models are estimated for four English-speaking countries (England, Canada, Australia and the USA), which include controls for comparable…
Yahata, Yoshio; Masuda, Yoshiko; Komabayashi, Takashi
2017-12-01
The aim of this study was to compare the apical centring ability of incisal-shifted access (ISA) with that of traditional lingual access (TLA). Fifteen three-dimensional printed resin models were prepared from the computed tomography data for a human maxillary central incisor and divided into ISA (n = 7), TLA (n = 7) and control (n = 1) groups. After access preparation, these models were shaped to the working length using K-files up to #40, followed by step-back procedures. An apical portion of the model was removed at 0.5 mm coronal to the working length. Microscopic images of each cutting surface were taken to measure the preparation area and the distance of transportation. TLA created a larger preparation area than ISA (P < 0.05). The distance of transportation (mean ± standard deviation) was 0.4 ± 0.1 mm for ISA and 0.7 ± 0.1 mm for TLA (P < 0.05). Access cavity preparation has a significant effect on apical centring ability. ISA is beneficial to maintaining apical configuration. © 2017 Australian Society of Endodontology Inc.
NASA Technical Reports Server (NTRS)
Trauger, John
2008-01-01
Topics include and overview, science objectives, study objectives, coronagraph types, metrics, ACCESS observatory, laboratory validations, and summary. Individual slides examine ACCESS engineering approach, ACCESS gamut of coronagraph types, coronagraph metrics, ACCESS Discovery Space, coronagraph optical layout, wavefront control on the "level playing field", deformable mirror development for HCIT, laboratory testbed demonstrations, high contract imaging with the HCIT, laboratory coronagraph contrast and stability, model validation and performance predictions, HCIT coronagraph optical layout, Lyot coronagraph on the HCIT, pupil mapping (PIAA), shaped pupils, and vortex phase mask experiments on the HCIT.
DOE`s nation-wide system for access control can solve problems for the federal government
DOE Office of Scientific and Technical Information (OSTI.GOV)
Callahan, S.; Tomes, D.; Davis, G.
1996-07-01
The U.S. Department of Energy`s (DOE`s) ongoing efforts to improve its physical and personnel security systems while reducing its costs, provide a model for federal government visitor processing. Through the careful use of standardized badges, computer databases, and networks of automated access control systems, the DOE is increasing the security associated with travel throughout the DOE complex, and at the same time, eliminating paperwork, special badging, and visitor delays. The DOE is also improving badge accountability, personnel identification assurance, and access authorization timeliness and accuracy. Like the federal government, the DOE has dozens of geographically dispersed locations run by manymore » different contractors operating a wide range of security systems. The DOE has overcome these obstacles by providing data format standards, a complex-wide virtual network for security, the adoption of a standard high security system, and an open-systems-compatible link for any automated access control system. If the location`s level of security requires it, positive visitor identification is accomplished by personal identification number (PIN) and/or by biometrics. At sites with automated access control systems, this positive identification is integrated into the portals.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-04
... Agencywide Documents Access and Management System (ADAMS) under Accession Number ML092670242. The proposed... and Maintenance Program'' is being proposed for Section [5.5] [``Administrative Controls--Programs and... and Management System (ADAMS): Publicly available documents created or received at the NRC are...
Healthcare teams over the Internet: programming a certificate-based approach.
Georgiadis, Christos K; Mavridis, Ioannis K; Pangalos, George I
2003-07-01
Healthcare environments are a representative case of collaborative environments since individuals (e.g. doctors) in many cases collaborate in order to provide care to patients in a more proficient way. At the same time modern healthcare institutions are increasingly interested in sharing access of their information resources in the networked environment. Healthcare applications over the Internet offer an attractive communication infrastructure at worldwide level but with a noticeably great factor of risk. Security has, therefore, become a major concern. However, although an adequate level of security can be relied upon digital certificates, if an appropriate security model is used, additional security considerations are needed in order to deal efficiently with the above team-work concerns. The already known Hybrid Access Control (HAC) security model supports and handles efficiently healthcare teams with active security capabilities and is capable to exploit the benefits of certificate technology. In this paper we present the way for encoding the appropriate authoritative information in various types of certificates, as well as the overall operational architecture of the implemented access control system for healthcare collaborative environments over the Internet. A pilot implementation of the proposed methodology in a major Greek hospital has shown the applicability of the proposals and the flexibility of the access control provided.
Multiple Memory Stores and Operant Conditioning: A Rationale for Memory's Complexity
ERIC Educational Resources Information Center
Meeter, Martijn; Veldkamp, Rob; Jin, Yaochu
2009-01-01
Why does the brain contain more than one memory system? Genetic algorithms can play a role in elucidating this question. Here, model animals were constructed containing a dorsal striatal layer that controlled actions, and a ventral striatal layer that controlled a dopaminergic learning signal. Both layers could gain access to three modeled memory…
Design of an Efficient CAC for a Broadband DVB-S/DVB-RCS Satellite Access Network
NASA Astrophysics Data System (ADS)
Inzerilli, Tiziano; Montozzi, Simone
2003-07-01
This paper deals with efficient utilization of network resources in an advanced broadband satellite access system. It proposes a technique for admission control of IP streams with guaranteed QoS which does not interfere with the particular BoD (Bandwidth on Demand) algorithm that handles access to uplink bandwidth, an essential part of a DVB- RCS architecture. This feature of the admission control greatly simplify its integration in the satellite network. The purpose of this admission control algorithm in particular is to suitably and dynamically configure the overall traffic control parameters, in the access terminal of the user and service segment, with a simple approach which does not introduces limitations and/or constraints to the BoD algorithm. Performance of the proposed algorithm is evaluated thorugh Opnet simulations using an ad-hoc platform modeling DVB-based satellite access.The results presented in this paper were obtained within SATIP6 project, which is sponsored within the 5th EU Research Programme, IST. The aims of the project are to evaluate and demonstrate key issues of the integration of satellite-based access networks into the Internet in order to support multimedia services over wide areas. The satellite link layer is based on DVB-S on the forward link and DVB-RCS on the return link. Adaptation and optimization of the DVB-RCS access standard in order to support QoS provision are central issues of the project. They are handled through an integration of Connection Admission Control (CAC), Traffic Shaping and Policing techniques.
Multiple Phase Transitions in the Culture Dissemination
NASA Astrophysics Data System (ADS)
Wang, Bing; Han, Yuexing; Chen, Luonan; Aihara, Kazuyuki
We study the coevolution process in the Axelrod’s model with the consideration of agents’ abilities to access to the information. With a parameter to control the ability of communication, we observe two kinds of phase transitions both for cultural domains and network fragments, respectively. With the simulation results, we find the relationship between the critical value and the controlled parameter. The results indicate that the powerful ability to access to the information benefits the dissemination of culture in the system.
Privacy and Access Control for IHE-Based Systems
NASA Astrophysics Data System (ADS)
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.
SPACEHAB missions as pathfinders for ISS services development
NASA Astrophysics Data System (ADS)
Hamill, Doris; Jackson, Kenneth; Mirra, Carlo
2003-01-01
SPACEHAB, Inc. has established a commercial business model for providing access to space. The model, based on private initiative and investment, has offered "turn key" access to space including both launch and integration and operations services. Some features of this business model should be applied directly to providing service in the ISS era: offering packaged service at a fixed price; customer focus; private investment as the basis for offering services; and efficient and continually improving customer service. But International Space Station (ISS) will pose challenges that have not been pioneered in the STS era: a new base of customers must be developed; on-orbit hardware will be more difficult to modify; access to ISS is controlled by government space agencies. These problems will tax the ingenuity of those who wish to provide services in space on a commercial business model.
Locally Controlled Scholarly Publishing via the Internet: The Guild Model.
ERIC Educational Resources Information Center
Kling, Rob; Spector, Lisa; McKim, Geoff
2002-01-01
Discusses use of the Internet for scholarly communication; describes five publishing models where readers can access articles without a fee, including electronic journals; and explains a sixth model, called the Guild Publishing Model, which involves research publication series called working papers or technical reports that are sponsored by…
Wood, Eric; Duran, Adam; Kelly, Kenneth
2016-09-27
In collaboration with the U.S. Environmental Protection Agency and the U.S. Department of Energy, the National Renewable Energy Laboratory has conducted a national analysis of road grade characteristics experienced by U.S. medium- and heavy-duty trucks on controlled access highways. These characteristics have been developed using TomTom's commercially available street map and road grade database. Using the TomTom national road grade database, national statistics on road grade and hill distances were generated for the U.S. network of controlled access highways. These statistical distributions were then weighted using data provided by the U.S. Environmental Protection Agency for activity of medium- and heavy-dutymore » trucks on controlled access highways. Here, the national activity-weighted road grade and hill distance distributions were then used as targets for development of a handful of sample grade profiles potentially to be used in the U.S. Environmental Protection Agency's Greenhouse Gas Emissions Model certification tool as well as in dynamometer testing of medium- and heavy-duty vehicles and their powertrains.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Eric; Duran, Adam; Kelly, Kenneth
In collaboration with the U.S. Environmental Protection Agency and the U.S. Department of Energy, the National Renewable Energy Laboratory has conducted a national analysis of road grade characteristics experienced by U.S. medium- and heavy-duty trucks on controlled access highways. These characteristics have been developed using TomTom's commercially available street map and road grade database. Using the TomTom national road grade database, national statistics on road grade and hill distances were generated for the U.S. network of controlled access highways. These statistical distributions were then weighted using data provided by the U.S. Environmental Protection Agency for activity of medium- and heavy-dutymore » trucks on controlled access highways. Here, the national activity-weighted road grade and hill distance distributions were then used as targets for development of a handful of sample grade profiles potentially to be used in the U.S. Environmental Protection Agency's Greenhouse Gas Emissions Model certification tool as well as in dynamometer testing of medium- and heavy-duty vehicles and their powertrains.« less
McCarty, Elizabeth; Morress, Claire
2009-08-01
Children with a diagnosis of cerebral palsy often have significant physical limitations that prevent exploration and full participation in the environment. Assistive technology systems can provide opportunities for children with physical limitations to interact with their world, enabling play, communication, and daily living skills. Efficient access to and control of the technology is critical for successful use; however, establishing consistent access is often difficult because of the nature of the movement patterns exhibited by children with cerebral palsy. This article describes a 3-phase model of evaluation and intervention developed and used by Assistive Technology Services at the Aaron W. Perlman Center, Cincinnati Children's Hospital Medical Center, to establish successful access to technology systems in children with cerebral palsy.
Biomedical Big Data: New Models of Control Over Access, Use and Governance.
Vayena, Effy; Blasimme, Alessandro
2017-12-01
Empirical evidence suggests that while people hold the capacity to control their data in high regard, they increasingly experience a loss of control over their data in the online world. The capacity to exert control over the generation and flow of personal information is a fundamental premise to important values such as autonomy, privacy, and trust. In healthcare and clinical research this capacity is generally achieved indirectly, by agreeing to specific conditions of informational exposure. Such conditions can be openly stated in informed consent documents or be implicit in the norms of confidentiality that govern the relationships of patients and healthcare professionals. However, with medicine becoming a data-intense enterprise, informed consent and medical confidentiality, as mechanisms of control, are put under pressure. In this paper we explore emerging models of informational control in data-intense healthcare and clinical research, which can compensate for the limitations of currently available instruments. More specifically, we discuss three approaches that hold promise in increasing individual control: the emergence of data portability rights as means to control data access, new mechanisms of informed consent as tools to control data use, and finally, new participatory governance schemes that allow individuals to control their data through direct involvement in data governance. We conclude by suggesting that, despite the impression that biomedical big data diminish individual control, the synergistic effect of new data management models can in fact improve it.
ERIC Educational Resources Information Center
Hill, Linda L.; Crosier, Scott J.; Smith, Terrence R.; Goodchild, Michael; Iannella, Renato; Erickson, John S.; Reich, Vicky; Rosenthal, David S. H.
2001-01-01
Includes five articles. Topics include requirements for a content standard to describe computational models; architectures for digital rights management systems; access control for digital information objects; LOCKSS (Lots of Copies Keep Stuff Safe) that allows libraries to run Web caches for specific journals; and a Web site from the U.S.…
Virtual collaborative environments: programming and controlling robotic devices remotely
NASA Astrophysics Data System (ADS)
Davies, Brady R.; McDonald, Michael J., Jr.; Harrigan, Raymond W.
1995-12-01
This paper describes a technology for remote sharing of intelligent electro-mechanical devices. An architecture and actual system have been developed and tested, based on the proposed National Information Infrastructure (NII) or Information Highway, to facilitate programming and control of intelligent programmable machines (like robots, machine tools, etc.). Using appropriate geometric models, integrated sensors, video systems, and computing hardware; computer controlled resources owned and operated by different (in a geographic sense as well as legal sense) entities can be individually or simultaneously programmed and controlled from one or more remote locations. Remote programming and control of intelligent machines will create significant opportunities for sharing of expensive capital equipment. Using the technology described in this paper, university researchers, manufacturing entities, automation consultants, design entities, and others can directly access robotic and machining facilities located across the country. Disparate electro-mechanical resources will be shared in a manner similar to the way supercomputers are accessed by multiple users. Using this technology, it will be possible for researchers developing new robot control algorithms to validate models and algorithms right from their university labs without ever owning a robot. Manufacturers will be able to model, simulate, and measure the performance of prospective robots before selecting robot hardware optimally suited for their intended application. Designers will be able to access CNC machining centers across the country to fabricate prototypic parts during product design validation. An existing prototype architecture and system has been developed and proven. Programming and control of a large gantry robot located at Sandia National Laboratories in Albuquerque, New Mexico, was demonstrated from such remote locations as Washington D.C., Washington State, and Southern California.
Network support for turn-taking in multimedia collaboration
NASA Astrophysics Data System (ADS)
Dommel, Hans-Peter; Garcia-Luna-Aceves, Jose J.
1997-01-01
The effectiveness of collaborative multimedia systems depends on the regulation of access to their shared resources, such as continuous media or instruments used concurrently by multiple parties. Existing applications use only simple protocols to mediate such resource contention. Their cooperative rules follow a strict agenda and are largely application-specific. The inherent problem of floor control lacks a systematic methodology. This paper presents a general model on floor control for correct, scalable, fine-grained and fair resource sharing that integrates user interaction with network conditions, and adaptation to various media types. The motion of turn-taking known from psycholinguistics in studies on discourse structure is adapted for this framework. Viewed as a computational analogy to speech communication, online collaboration revolves around dynamically allocated access permissions called floors. The control semantics of floors derives from concurrently control methodology. An explicit specification and verification of a novel distributed Floor Control Protocol are presented. Hosts assume sharing roles that allow for efficient dissemination of control information, agreeing on a floor holder which is granted mutually exclusive access to a resource. Performance analytic aspects of floor control protocols are also briefly discussed.
NASA Technical Reports Server (NTRS)
Patre, Parag; Joshi, Suresh M.
2011-01-01
Decentralized adaptive control is considered for systems consisting of multiple interconnected subsystems. It is assumed that each subsystem s parameters are uncertain and the interconnection parameters are not known. In addition, mismatch can exist between each subsystem and its reference model. A strictly decentralized adaptive control scheme is developed, wherein each subsystem has access only to its own state but has the knowledge of all reference model states. The mismatch is estimated online for each subsystem and the mismatch estimates are used to adaptively modify the corresponding reference models. The adaptive control scheme is extended to the case with actuator failures in addition to mismatch.
Hürlimann, Eveline; Schur, Nadine; Boutsika, Konstantina; Stensgaard, Anna-Sofie; Laserna de Himpsl, Maiti; Ziegelbauer, Kathrin; Laizer, Nassor; Camenzind, Lukas; Di Pasquale, Aurelio; Ekpo, Uwem F; Simoonga, Christopher; Mushinge, Gabriel; Saarnak, Christopher F L; Utzinger, Jürg; Kristensen, Thomas K; Vounatsou, Penelope
2011-12-01
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. 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. 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. 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 and running of a global NTD database is feasible and should be expanded without delay.
Sibling rivalry: training effects, emergence of dominance and incomplete control.
Benhaiem, Sarah; Hofer, Heribert; Kramer-Schadt, Stephanie; Brunner, Edgar; East, Marion L
2012-09-22
Within-brood or -litter dominance provides fitness-related benefits if dominant siblings selfishly skew access to food provided by parents in their favour. Models of facultative siblicide assume that dominants exert complete control over their subordinate sibling's access to food and that control is maintained, irrespective of the subordinate's hunger level. By contrast, a recent functional hypothesis suggests that subordinates should contest access to food when the cost of not doing so is high. Here, we show that within spotted hyena (Crocuta crocuta) twin litters, dominants most effectively skew access to maternal milk in their favour when their aggression prompts a highly submissive response. When hungry, subordinates were less submissive in response to aggression, thereby decreasing lost suckling time and increasing suckling time lost by dominants. In a species where adult females socially dominate adult males, juvenile females were more often dominant than males in mixed-sex litters, and subordinate sisters used more effective counter-tactics against dominant brothers than subordinate brothers against dominant sisters. Our results provide, to our knowledge, the first evidence in a mammal that dominant offspring in twin litters do not exert complete control over their sibling's access to resources (milk), and that sibling dominance relationships are influenced by sibling sex and training effects.
Sibling rivalry: training effects, emergence of dominance and incomplete control
Benhaiem, Sarah; Hofer, Heribert; Kramer-Schadt, Stephanie; Brunner, Edgar; East, Marion L.
2012-01-01
Within-brood or -litter dominance provides fitness-related benefits if dominant siblings selfishly skew access to food provided by parents in their favour. Models of facultative siblicide assume that dominants exert complete control over their subordinate sibling's access to food and that control is maintained, irrespective of the subordinate's hunger level. By contrast, a recent functional hypothesis suggests that subordinates should contest access to food when the cost of not doing so is high. Here, we show that within spotted hyena (Crocuta crocuta) twin litters, dominants most effectively skew access to maternal milk in their favour when their aggression prompts a highly submissive response. When hungry, subordinates were less submissive in response to aggression, thereby decreasing lost suckling time and increasing suckling time lost by dominants. In a species where adult females socially dominate adult males, juvenile females were more often dominant than males in mixed-sex litters, and subordinate sisters used more effective counter-tactics against dominant brothers than subordinate brothers against dominant sisters. Our results provide, to our knowledge, the first evidence in a mammal that dominant offspring in twin litters do not exert complete control over their sibling's access to resources (milk), and that sibling dominance relationships are influenced by sibling sex and training effects. PMID:22719032
NASA Astrophysics Data System (ADS)
Jian, Wei; Estevez, Claudio; Chowdhury, Arshad; Jia, Zhensheng; Wang, Jianxin; Yu, Jianguo; Chang, Gee-Kung
2010-12-01
This paper presents an energy-efficient Medium Access Control (MAC) protocol for very-high-throughput millimeter-wave (mm-wave) wireless sensor communication networks (VHT-MSCNs) based on hybrid multiple access techniques of frequency division multiplexing access (FDMA) and time division multiplexing access (TDMA). An energy-efficient Superframe for wireless sensor communication network employing directional mm-wave wireless access technologies is proposed for systems that require very high throughput, such as high definition video signals, for sensing, processing, transmitting, and actuating functions. Energy consumption modeling for each network element and comparisons among various multi-access technologies in term of power and MAC layer operations are investigated for evaluating the energy-efficient improvement of proposed MAC protocol.
Left Ventrolateral Prefrontal Cortex and the Cognitive Control of Memory
ERIC Educational Resources Information Center
Badre, David; Wagner, Anthony D.
2007-01-01
Cognitive control mechanisms permit memory to be accessed strategically, and so aid in bringing knowledge to mind that is relevant to current goals and actions. In this review, we consider the contribution of left ventrolateral prefrontal cortex (VLPFC) to the cognitive control of memory. Reviewed evidence supports a two-process model of mnemonic…
Detecting Payload Attacks on Programmable Logic Controllers (PLCs)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Huan
Programmable logic controllers (PLCs) play critical roles in industrial control systems (ICS). Providing hardware peripherals and firmware support for control programs (i.e., a PLC’s “payload”) written in languages such as ladder logic, PLCs directly receive sensor readings and control ICS physical processes. An attacker with access to PLC development software (e.g., by compromising an engineering workstation) can modify the payload program and cause severe physical damages to the ICS. To protect critical ICS infrastructure, we propose to model runtime behaviors of legitimate PLC payload program and use runtime behavior monitoring in PLC firmware to detect payload attacks. By monitoring themore » I/O access patterns, network access patterns, as well as payload program timing characteristics, our proposed firmware-level detection mechanism can detect abnormal runtime behaviors of malicious PLC payload. Using our proof-of-concept implementation, we evaluate the memory and execution time overhead of implementing our proposed method and find that it is feasible to incorporate our method into existing PLC firmware. In addition, our evaluation results show that a wide variety of payload attacks can be effectively detected by our proposed approach. The proposed firmware-level payload attack detection scheme complements existing bumpin- the-wire solutions (e.g., external temporal-logic-based model checkers) in that it can detect payload attacks that violate realtime requirements of ICS operations and does not require any additional apparatus.« less
The Use of a Computer-Controlled Random Access Slide Projector for Rapid Information Display.
ERIC Educational Resources Information Center
Muller, Mark T.
A 35mm random access slide projector operated in conjunction with a computer terminal was adapted to meet the need for a more rapid and complex graphic display mechanism than is currently available with teletypewriter terminals. The model projector can be operated manually to provide for a maintenance checkout of the electromechanical system.…
Wireless Sensor Network Radio Power Management and Simulation Models
2010-01-01
The Open Electrical & Electronic Engineering Journal, 2010, 4, 21-31 21 1874-1290/10 2010 Bentham Open Open Access Wireless Sensor Network Radio...Air Force Institute of Technology, Wright-Patterson AFB, OH, USA Abstract: Wireless sensor networks (WSNs) create a new frontier in collecting and...consumption. Keywords: Wireless sensor network , power management, energy-efficiency, medium access control (MAC), simulation pa- rameters. 1
A development framework for artificial intelligence based distributed operations support systems
NASA Technical Reports Server (NTRS)
Adler, Richard M.; Cottman, Bruce H.
1990-01-01
Advanced automation is required to reduce costly human operations support requirements for complex space-based and ground control systems. Existing knowledge based technologies have been used successfully to automate individual operations tasks. Considerably less progress has been made in integrating and coordinating multiple operations applications for unified intelligent support systems. To fill this gap, SOCIAL, a tool set for developing Distributed Artificial Intelligence (DAI) systems is being constructed. SOCIAL consists of three primary language based components defining: models of interprocess communication across heterogeneous platforms; models for interprocess coordination, concurrency control, and fault management; and for accessing heterogeneous information resources. DAI applications subsystems, either new or existing, will access these distributed services non-intrusively, via high-level message-based protocols. SOCIAL will reduce the complexity of distributed communications, control, and integration, enabling developers to concentrate on the design and functionality of the target DAI system itself.
Transgender Adults' Access to College Bathrooms and Housing and the Relationship to Suicidality.
Seelman, Kristie L
2016-10-01
Transgender and gender non-conforming people frequently experience discrimination, harassment, and marginalization across college and university campuses (Bilodeau, 2007; Finger, 2010; Rankin et al., 2010; Seelman et al., 2012). The minority stress model (Meyer, 2007) posits that experiences of discrimination often negatively impact the psychological wellbeing of minority groups. However, few scholars have examined whether college institutional climate factors-such as being denied access to bathrooms or gender-appropriate campus housing-are significantly associated with detrimental psychological outcomes for transgender people. Using the National Transgender Discrimination Survey, this study analyzes whether being denied access to these spaces is associated with lifetime suicide attempts, after controlling for interpersonal victimization by students or teachers. Findings from sequential logistic regression (N = 2,316) indicate that denial of access to either space had a significant relationship to suicidality, even after controlling for interpersonal victimization. This article discusses implications for higher education professionals and researchers.
Access control mechanism of wireless gateway based on open flow
NASA Astrophysics Data System (ADS)
Peng, Rong; Ding, Lei
2017-08-01
In order to realize the access control of wireless gateway and improve the access control of wireless gateway devices, an access control mechanism of SDN architecture which is based on Open vSwitch is proposed. The mechanism utilizes the features of the controller--centralized control and programmable. Controller send access control flow table based on the business logic. Open vSwitch helps achieve a specific access control strategy based on the flow table.
Nesting behavior of house mice (Mus domesticus) selected for increased wheel-running activity.
Carter, P A; Swallow, J G; Davis, S J; Garland, T
2000-03-01
Nest building was measured in "active" (housed with access to running wheels) and "sedentary" (without wheel access) mice (Mus domesticus) from four replicate lines selected for 10 generations for high voluntary wheel-running behavior, and from four randombred control lines. Based on previous studies of mice bidirectionally selected for thermoregulatory nest building, it was hypothesized that nest building would show a negative correlated response to selection on wheel-running. Such a response could constrain the evolution of high voluntary activity because nesting has also been shown to be positively genetically correlated with successful production of weaned pups. With wheel access, selected mice of both sexes built significantly smaller nests than did control mice. Without wheel access, selected females also built significantly smaller nests than did control females, but only when body mass was excluded from the statistical model, suggesting that body mass mediated this correlated response to selection. Total distance run and mean running speed on wheels was significantly higher in selected mice than in controls, but no differences in amount of time spent running were measured, indicating a complex cause of the response of nesting to selection for voluntary wheel running.
Shi, Leiyu; Stevens, Gregory D
2005-01-01
The study assessed the progress made toward reducing racial and ethnic disparities in access to health care among U.S. children between 1996 and 2000. Data are from the Household Component of the 1996 and 2000 Medical Expenditure Panel Survey. Bivariate associations of combinations of race/ethnicity and poverty status groups were examined with four measures of access to health care and a single measure of satisfaction. Logistic regression was used to examine the association of race/ethnicity with access, controlling for sociodemographic factors associated with access to care. To highlight the role of income, we present models with and without controlling for poverty status. Racial and ethnic minority children experience significant deficits in accessing medical care compared with whites. Asians, Hispanics, and blacks were less likely than whites to have a usual source of care, health professional or doctor visit, and dental visit in the past year. Asians were more likely than whites to be dissatisfied with the quality of medical care in 2000 (but not 1996), while blacks and Hispanics were more likely than whites to be dissatisfied with the quality of medical care in 1996 (but not in 2000). Both before and after controlling for health insurance coverage, poverty status, health status, and several other factors associated with access to care, these disparities in access to care persisted between 1996 and 2000. Continued monitoring of racial and ethnic differences is necessary in light of the persistence of racial/ethnic and socioeconomic disparities in access to care. Given national goals to achieve equity in health care and eliminate racial/ ethnic disparities in health, greater attention needs to be paid to the interplay of race/ethnicity factors and poverty status in influencing access.
A hierarchical distributed control model for coordinating intelligent systems
NASA Technical Reports Server (NTRS)
Adler, Richard M.
1991-01-01
A hierarchical distributed control (HDC) model for coordinating cooperative problem-solving among intelligent systems is described. The model was implemented using SOCIAL, an innovative object-oriented tool for integrating heterogeneous, distributed software systems. SOCIAL embeds applications in 'wrapper' objects called Agents, which supply predefined capabilities for distributed communication, control, data specification, and translation. The HDC model is realized in SOCIAL as a 'Manager'Agent that coordinates interactions among application Agents. The HDC Manager: indexes the capabilities of application Agents; routes request messages to suitable server Agents; and stores results in a commonly accessible 'Bulletin-Board'. This centralized control model is illustrated in a fault diagnosis application for launch operations support of the Space Shuttle fleet at NASA, Kennedy Space Center.
Finite-dimensional modeling of network-induced delays for real-time control systems
NASA Technical Reports Server (NTRS)
Ray, Asok; Halevi, Yoram
1988-01-01
In integrated control systems (ICS), a feedback loop is closed by the common communication channel, which multiplexes digital data from the sensor to the controller and from the controller to the actuator along with the data traffic from other control loops and management functions. Due to asynchronous time-division multiplexing in the network access protocols, time-varying delays are introduced in the control loop, which degrade the system dynamic performance and are a potential source of instability. The delayed control system is represented by a finite-dimensional, time-varying, discrete-time model which is less complex than the existing continuous-time models for time-varying delays; this approach allows for simpler schemes for analysis and simulation of the ICS.
An Extended Role-Based Access Control Model for Delegating Obligations
NASA Astrophysics Data System (ADS)
Ben-Ghorbel-Talbi, Meriam; Cuppens, Frédéric; Cuppens-Boulahia, Nora; Bouhoula, Adel
The main aim of access control models is to provide means to simplify the management of the security policy, which is a fastidious and error-prone task. Supporting delegation is considered as an important mean to decentralize the administration and therefore to allow security policy to be more flexible and easier to manipulate. Our main contribution is the proposition of a unified model to the administration and delegation of obligations. Managing such delegations implies more requirements than managing traditional privileges delegation. In fact, delegating obligations may include two interpretations: the delegation of the obligation and the delegation of the responsibility related to this obligation. Therefore, it is important to deal with these two notions separately. Moreover, since delegating an obligation involves the delegation of sanctions, then the consent of the user who receives this delegation may be required in some cases. We address in this paper these requirements and we propose a formalism to deal with them.
Model-Driven Configuration of SELinux Policies
NASA Astrophysics Data System (ADS)
Agreiter, Berthold; Breu, Ruth
The need for access control in computer systems is inherent. However, the complexity to configure such systems is constantly increasing which affects the overall security of a system negatively. We think that it is important to define security requirements on a non-technical level while taking the application domain into respect in order to have a clear and separated view on security configuration (i.e. unblurred by technical details). On the other hand, security functionality has to be tightly integrated with the system and its development process in order to provide comprehensive means of enforcement. In this paper, we propose a systematic approach based on model-driven security configuration to leverage existing operating system security mechanisms (SELinux) for realising access control. We use UML models and develop a UML profile to satisfy these needs. Our goal is to exploit a comprehensive protection mechanism while rendering its security policy manageable by a domain specialist.
Ragonnet, Romain; Trauer, James M; Denholm, Justin T; Marais, Ben J; McBryde, Emma S
2017-05-30
Multidrug-resistant and rifampicin-resistant tuberculosis (MDR/RR-TB) represent an important challenge for global tuberculosis (TB) control. The high rates of MDR/RR-TB observed among re-treatment cases can arise from diverse pathways: de novo amplification during initial treatment, inappropriate treatment of undiagnosed MDR/RR-TB, relapse despite appropriate treatment, or reinfection with MDR/RR-TB. Mathematical modelling allows quantification of the contribution made by these pathways in different settings. This information provides valuable insights for TB policy-makers, allowing better contextualised solutions. However, mathematical modelling outputs need to consider local data and be easily accessible to decision makers in order to improve their usefulness. We present a user-friendly web-based modelling interface, which can be used by people without technical knowledge. Users can input their own parameter values and produce estimates for their specific setting. This innovative tool provides easy access to mathematical modelling outputs that are highly relevant to national TB control programs. In future, the same approach could be applied to a variety of modelling applications, enhancing local decision making.
Koehlmoos, Tracey Perez; Gazi, Rukhsana; Hossain, S Shahed; Zaman, K
2009-01-21
Social franchising has developed as a possible means of improving provision of health services through engaging the non-state sector in low- and middle-income countries. To examine the evidence that social franchising has on access to and quality of health services in low- and middle-income countries. We searched the Cochrane Effective Practice and Organisation of Care (EPOC) Group Specialised Register (up to October 2007), Cochrane Central Register of Controlled Trials (The Cochrane Library 2007, Issue 3), MEDLINE, Ovid (1950 to September Week 3 2007), EMBASE, Ovid (1980 to 2007 Week 38), CINAHL, Ovid (1982 to September Week 3 2007), EconLit, WebSPIRS (1969 to Sept 2007), LILACS, Science Citation Index Expanded and Social Sciences Citation Index (1975 to March 2008), Sociological Abstracts, CSA Illumnia (1952 September 2007), WHOLIS (1948 November 2007). Randomized controlled trials, non-randomized controlled trials, controlled before and after studies and interrupted time series comparing social franchising models with other models of health service delivery, other social franchising models or absence of health services. Two review authors independently applied the criteria for inclusion and exclusion of studies to scan titles and abstracts. The same two review authors independently screened full reports of selected citations . At each stage, results were compared and discrepancies settled through discussion. No studies were found which were eligible for inclusion in this review. There is a need to develop rigorous studies to evaluate the effects of social franchising on access to and quality of health services in low- and middle-income countries. Such studies should be informed by the wider literature to identify models of social franchising that have a sound theoretical basis and empirical research addressing their reach, acceptability, feasibility, maintenance and measurability.
Limited ability driven phase transitions in the coevolution process in Axelrod's model
NASA Astrophysics Data System (ADS)
Wang, Bing; Han, Yuexing; Chen, Luonan; Aihara, Kazuyuki
2009-04-01
We study the coevolution process in Axelrod's model by taking into account of agents' abilities to access information, which is described by a parameter α to control the geographical range of communication. We observe two kinds of phase transitions in both cultural domains and network fragments, which depend on the parameter α. By simulation, we find that not all rewiring processes pervade the dissemination of culture, that is, a very limited ability to access information constrains the cultural dissemination, while an exceptional ability to access information aids the dissemination of culture. Furthermore, by analyzing the network characteristics at the frozen states, we find that there exists a stage at which the network develops to be a small-world network with community structures.
Levy, David T.; Hyland, Andrew; Higbee, Cheryl; Remer, Lillian; Compton, Christine
2009-01-01
Summary Tobacco control policies are examined utilizing a simulation model for California, the state with the longest running comprehensive program. We assess the impact of the California Tobacco Control Program (CTCP) and surrounding price changes on smoking prevalence and smoking-attributable deaths. Modeling begins in 1988 and progresses chronologically to 2004, and considers four types of policies (taxes, mass media, clean air laws, and youth access policies) independently and as a package. The model is validated against existing smoking prevalence estimates. The difference in trends between predicted smoking rates from the model and other commonly used estimates of smoking prevalence for the overall period were generally small. The model also predicted some important changes in trend, which occurred with changes in policy. The California SimSmoke model estimates that tobacco control policies reduced smoking rates in California by an additional 25% relative to the level that they would have been if policies were kept at their 1988 level. By 2004, the model attributes over 60% of the reduction to price increases, over 25% of the overall effect to media policies, 10% to clean air laws, and only a small percent to youth access policies. The model estimates that over 5,000 lives will be saved in the year 2010 alone as a result of the CTCP and industry-initiated price increases, and that over 50,000 lives were saved over the period 1988-2010. Tobacco control policies implemented as comprehensive tobacco control strategies have significantly impacted smoking rates. Further tax increases should lead to additional lives saved, and additional policies may result in further impacts on smoking rates, and consequently on smoking-attributable health outcomes in the population. PMID:17055104
Estimation and modeling of coal pore accessibility using small angle neutron scattering
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Rui; Liu, Shimin; Bahadur, Jitendra
Gas diffusion in coal is controlled by nano-structure of the pores. The interconnectivity of pores not only determines the dynamics of gas transport in the coal matrix but also influences the mechanical strength. In this study, small angle neutron scattering (SANS) was employed to quantify pore accessibility for two coal samples, one of sub-bituminous rank and the other of anthracite rank. Moreover, a theoretical pore accessibility model was proposed based on scattering intensities under both vacuum and zero average contrast (ZAC) conditions. Our results show that scattering intensity decreases with increasing gas pressure using deuterated methane (CD 4) at lowmore » Q values for both coals. Pores smaller than 40 nm in radius are less accessible for anthracite than sub-bituminous coal. On the contrary, when the pore radius is larger than 40 nm, the pore accessibility of anthracite becomes larger than that of sub-bituminous coal. Only 20% of pores are accessible to CD 4 for anthracite and 37% for sub-bituminous coal, where the pore radius is 16 nm. For these two coals, pore accessibility and pore radius follows a power-law relationship.« less
Estimation and modeling of coal pore accessibility using small angle neutron scattering
Zhang, Rui; Liu, Shimin; Bahadur, Jitendra; ...
2015-09-04
Gas diffusion in coal is controlled by nano-structure of the pores. The interconnectivity of pores not only determines the dynamics of gas transport in the coal matrix but also influences the mechanical strength. In this study, small angle neutron scattering (SANS) was employed to quantify pore accessibility for two coal samples, one of sub-bituminous rank and the other of anthracite rank. Moreover, a theoretical pore accessibility model was proposed based on scattering intensities under both vacuum and zero average contrast (ZAC) conditions. Our results show that scattering intensity decreases with increasing gas pressure using deuterated methane (CD 4) at lowmore » Q values for both coals. Pores smaller than 40 nm in radius are less accessible for anthracite than sub-bituminous coal. On the contrary, when the pore radius is larger than 40 nm, the pore accessibility of anthracite becomes larger than that of sub-bituminous coal. Only 20% of pores are accessible to CD 4 for anthracite and 37% for sub-bituminous coal, where the pore radius is 16 nm. For these two coals, pore accessibility and pore radius follows a power-law relationship.« less
The Effect of Community Uninsurance Rates on Access to Health Care
Sabik, Lindsay M
2012-01-01
Objective To investigate the effect of local uninsurance rates on access to health care for the uninsured and insured and improve on recent studies by controlling for time-invariant differences across markets. Data Sources Individual-level data from the 1996 and 2003 Community Tracking Study, and market-level data from other sources, including the Area Resource File and the Bureau of Primary Healthcare. Study Design Market-level fixed effects models estimate the effect of changes in uninsurance rates within markets on access to care, measured by whether individuals report forgoing necessary care. Instrumental variables models are also estimated. Principal Findings Increases in the rate of uninsurance are associated with poorer access to necessary care among the uninsured. In contrast with recent evidence, increases in uninsurance had no effect on access to care among the insured. Instrumental variables results are similar, although not statistically significant. Conclusions Changes in rates of insurance coverage are likely to affect access to care for both previously and continuously uninsured. In contrast with earlier studies, there is no evidence of spillover effects on the insured, suggesting that such policy changes may have little effect on access for those who are already insured. PMID:22172046
Mold, Freda; de Lusignan, Simon
2015-01-01
Online access to medical records and linked services, including requesting repeat prescriptions and booking appointments, enables patients to personalize their access to care. However, online access creates opportunities and challenges for both health professionals and their patients, in practices and in research. The challenges for practice are the impact of online services on workload and the quality and safety of health care. Health professionals are concerned about the impact on workload, especially from email or other online enquiry systems, as well as risks to privacy. Patients report how online access provides a convenient means through which to access their health provider and may offer greater satisfaction if they get a timely response from a clinician. Online access and services may also result in unforeseen consequences and may change the nature of the patient-clinician interaction. Research challenges include: (1) Ensuring privacy, including how to control inappropriate carer and guardian access to medical records; (2) Whether online access to records improves patient safety and health outcomes; (3) Whether record access increases disparities across social classes and between genders; and (4) Improving efficiency. The challenges for practice are: (1) How to incorporate online access into clinical workflow; (2) The need for a business model to fund the additional time taken. Creating a sustainable business model for a safe, private, informative, more equitable online service is needed if online access to records is to be provided outside of pay-for-service systems. PMID:26690225
Mold, Freda; de Lusignan, Simon
2015-12-04
Online access to medical records and linked services, including requesting repeat prescriptions and booking appointments, enables patients to personalize their access to care. However, online access creates opportunities and challenges for both health professionals and their patients, in practices and in research. The challenges for practice are the impact of online services on workload and the quality and safety of health care. Health professionals are concerned about the impact on workload, especially from email or other online enquiry systems, as well as risks to privacy. Patients report how online access provides a convenient means through which to access their health provider and may offer greater satisfaction if they get a timely response from a clinician. Online access and services may also result in unforeseen consequences and may change the nature of the patient-clinician interaction. Research challenges include: (1) Ensuring privacy, including how to control inappropriate carer and guardian access to medical records; (2) Whether online access to records improves patient safety and health outcomes; (3) Whether record access increases disparities across social classes and between genders; and (4) Improving efficiency. The challenges for practice are: (1) How to incorporate online access into clinical workflow; (2) The need for a business model to fund the additional time taken. Creating a sustainable business model for a safe, private, informative, more equitable online service is needed if online access to records is to be provided outside of pay-for-service systems.
Deladoëy, Johnny; Henderson, Mélanie; Geoffroy, Louis
2013-05-01
In health care systems with a user fee, the impact of socioeconomic factors on pediatric insulin-dependent diabetes mellitus (IDDM) control could be due to the cost of accessing care. There is a linear association between household income and the average glycosylated hemoglobin (HbA1c) of children and adolescents with IDDM despite free access to health care. We used a linear regression model to examine the association between normalized average HbA1c of 1766 diabetic children (diagnosed at our institution from 1980 to 2011 before 17 years of age) and the median household income of their neighborhoods (obtained from Statistics Canada, 2006 Census data). We found a negative linear association (P < .001; r = -0.2) between the level of income and metabolic control assessed by HbA1c after controlling for sex, age at diagnosis, duration of diabetes, ethnicity, geographical factors, frequency of visits, current age (as a proxy for change in practice over time), and change of measurement methods of HbA1c across time. For every increase of $15,000 in annual income, HbA1c decreased by 0.1%. We report a linear association of household income with metabolic control of IDDM in childhood. Given that Canada has a system of free universal access to health care, confounding by access to care is unlikely. Considering the impact of poorly controlled IDDM in childhood on the development of long-term complications, our findings suggest that the higher complication rate found in adults of low socioeconomic status might originate from the poor control that they experienced in childhood. Support for the care of IDDM children from low-income neighborhoods should be increased.
Efficient Access Control in Multimedia Social Networks
NASA Astrophysics Data System (ADS)
Sachan, Amit; Emmanuel, Sabu
Multimedia social networks (MMSNs) have provided a convenient way to share multimedia contents such as images, videos, blogs, etc. Contents shared by a person can be easily accessed by anybody else over the Internet. However, due to various privacy, security, and legal concerns people often want to selectively share the contents only with their friends, family, colleagues, etc. Access control mechanisms play an important role in this situation. With access control mechanisms one can decide the persons who can access a shared content and who cannot. But continuously growing content uploads and accesses, fine grained access control requirements (e.g. different access control parameters for different parts in a picture), and specific access control requirements for multimedia contents can make the time complexity of access control to be very large. So, it is important to study an efficient access control mechanism suitable for MMSNs. In this chapter we present an efficient bit-vector transform based access control mechanism for MMSNs. The proposed approach is also compatible with other requirements of MMSNs, such as access rights modification, content deletion, etc. Mathematical analysis and experimental results show the effectiveness and efficiency of our proposed approach.
Clearinghouse for Inventories and Emissions Factors
Emissions inventories, modeling, and monitoring are the basis for understanding, controlling and tracking stationary sources of air pollution. This technical site provides access to tools and data to support those efforts.
NASA Astrophysics Data System (ADS)
Radhakrishnan, A.; Balaji, V.; Schweitzer, R.; Nikonov, S.; O'Brien, K.; Vahlenkamp, H.; Burger, E. F.
2016-12-01
There are distinct phases in the development cycle of an Earth system model. During the model development phase, scientists make changes to code and parameters and require rapid access to results for evaluation. During the production phase, scientists may make an ensemble of runs with different settings, and produce large quantities of output, that must be further analyzed and quality controlled for scientific papers and submission to international projects such as the Climate Model Intercomparison Project (CMIP). During this phase, provenance is a key concern:being able to track back from outputs to inputs. We will discuss one of the paths taken at GFDL in delivering tools across this lifecycle, offering on-demand analysis of data by integrating the use of GFDL's in-house FRE-Curator, Unidata's THREDDS and NOAA PMEL's Live Access Servers (LAS).Experience over this lifecycle suggests that a major difficulty in developing analysis capabilities is only partially the scientific content, but often devoted to answering the questions "where is the data?" and "how do I get to it?". "FRE-Curator" is the name of a database-centric paradigm used at NOAA GFDL to ingest information about the model runs into an RDBMS (Curator database). The components of FRE-Curator are integrated into Flexible Runtime Environment workflow and can be invoked during climate model simulation. The front end to FRE-Curator, known as the Model Development Database Interface (MDBI) provides an in-house web-based access to GFDL experiments: metadata, analysis output and more. In order to provide on-demand visualization, MDBI uses Live Access Servers which is a highly configurable web server designed to provide flexible access to geo-referenced scientific data, that makes use of OPeNDAP. Model output saved in GFDL's tape archive, the size of the database and experiments, continuous model development initiatives with more dynamic configurations add complexity and challenges in providing an on-demand visualization experience to our GFDL users.
ERIC Educational Resources Information Center
Menon, Sanjay T.
2002-01-01
The context for health empowerment includes individuals, health providers, and the regulatory environment. Psychological health empowerment consists of perceived control, perceived competence, and goal internalization. In multicultural communities, barriers to empowerment include locus of control, access to health care, and language and cultural…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dykstra, D.; Blomer, J.
Both the CernVM File System (CVMFS) and the Frontier Distributed Database Caching System (Frontier) distribute centrally updated data worldwide for LHC experiments using http proxy caches. Neither system provides privacy or access control on reading the data, but both control access to updates of the data and can guarantee the authenticity and integrity of the data transferred to clients over the internet. CVMFS has since its early days required digital signatures and secure hashes on all distributed data, and recently Frontier has added X.509-based authenticity and integrity checking. In this paper we detail and compare the security models of CVMFSmore » and Frontier.« less
Benefits of detailed models of muscle activation and mechanics
NASA Technical Reports Server (NTRS)
Lehman, S. L.; Stark, L.
1981-01-01
Recent biophysical and physiological studies identified some of the detailed mechanisms involved in excitation-contraction coupling, muscle contraction, and deactivation. Mathematical models incorporating these mechanisms allow independent estimates of key parameters, direct interplay between basic muscle research and the study of motor control, and realistic model behaviors, some of which are not accessible to previous, simpler, models. The existence of previously unmodeled behaviors has important implications for strategies of motor control and identification of neural signals. New developments in the analysis of differential equations make the more detailed models feasible for simulation in realistic experimental situations.
NASA Astrophysics Data System (ADS)
Cinquini, L.; Bell, G. M.; Williams, D.; Harney, J.
2012-12-01
The Earth System Grid Federation (ESGF) is a multi-agency, international collaboration that aims at developing state-of-the-art services for the management and access of Earth system data. ESGF is currently used to serve the totality of the model output used for the forthcoming IPCC 5th assessment report on climate change, as well as supporting observational and reanalysis datasets. Also, it is been adopted by several other projects that focus on global, regional and local climate modeling. The ESGF software stack is composed of several modular applications that cover related but disjoint areas of functionality: data publishing, data search and discovery, data access, user management, security, and federation. Overall, the ESGF infrastructure offers a configurable end-to-end solution to the problem of enabling web-based access to large amounts of geospatial data. This talk will present the architectural and configuration options that are available to a data provider leveraging ESGF to serve their data: which services to expose, how to scale to larger data collections, how to establish access control, how to customize the user interface, and others. Additionally, the framework provides extension points that allow each site to plug in custom functionality such as crawling of specific metadata repositories, exposing domain-specific analysis and visualization services, developing custom access clients that interact with the system APIs. These configuration and extension capabilities are based on simple but effective domain-specific object models, that underpin the software applications: the data model, the security model, and the federation model. The ESGF software stack is developed collaboratively by software engineers at many institutions around the world, and is made freely available to the community under an open source license to promote adoption, reuse, inspection and continuous improvement.
Toward a Tiered Model to Share Clinical Trial Data and Samples in Precision Oncology.
Broes, Stefanie; Lacombe, Denis; Verlinden, Michiel; Huys, Isabelle
2018-01-01
The recent revolution in science and technology applied to medical research has left in its wake a trial of biomedical data and human samples; however, its opportunities remain largely unfulfilled due to a number of legal, ethical, financial, strategic, and technical barriers. Precision oncology has been at the vanguard to leverage this potential of "Big data" and samples into meaningful solutions for patients, considering the need for new drug development approaches in this area (due to high costs, late-stage failures, and the molecular diversity of cancer). To harness the potential of the vast quantities of data and samples currently fragmented across databases and biobanks, it is critical to engage all stakeholders and share data and samples across research institutes. Here, we identified two general types of sharing strategies. First, open access models, characterized by the absence of any review panel or decision maker, and second controlled access model where some form of control is exercised by either the donor (i.e., patient), the data provider (i.e., initial organization), or an independent party. Further, we theoretically describe and provide examples of nine different strategies focused on greater sharing of patient data and material. These models provide varying levels of control, access to various data and/or samples, and different types of relationship between the donor, data provider, and data requester. We propose a tiered model to share clinical data and samples that takes into account privacy issues and respects sponsors' legitimate interests. Its implementation would contribute to maximize the value of existing datasets, enabling unraveling the complexity of tumor biology, identify novel biomarkers, and re-direct treatment strategies better, ultimately to help patients with cancer.
Toward a Tiered Model to Share Clinical Trial Data and Samples in Precision Oncology
Broes, Stefanie; Lacombe, Denis; Verlinden, Michiel; Huys, Isabelle
2018-01-01
The recent revolution in science and technology applied to medical research has left in its wake a trial of biomedical data and human samples; however, its opportunities remain largely unfulfilled due to a number of legal, ethical, financial, strategic, and technical barriers. Precision oncology has been at the vanguard to leverage this potential of “Big data” and samples into meaningful solutions for patients, considering the need for new drug development approaches in this area (due to high costs, late-stage failures, and the molecular diversity of cancer). To harness the potential of the vast quantities of data and samples currently fragmented across databases and biobanks, it is critical to engage all stakeholders and share data and samples across research institutes. Here, we identified two general types of sharing strategies. First, open access models, characterized by the absence of any review panel or decision maker, and second controlled access model where some form of control is exercised by either the donor (i.e., patient), the data provider (i.e., initial organization), or an independent party. Further, we theoretically describe and provide examples of nine different strategies focused on greater sharing of patient data and material. These models provide varying levels of control, access to various data and/or samples, and different types of relationship between the donor, data provider, and data requester. We propose a tiered model to share clinical data and samples that takes into account privacy issues and respects sponsors’ legitimate interests. Its implementation would contribute to maximize the value of existing datasets, enabling unraveling the complexity of tumor biology, identify novel biomarkers, and re-direct treatment strategies better, ultimately to help patients with cancer. PMID:29435448
Hürlimann, Eveline; Schur, Nadine; Boutsika, Konstantina; Stensgaard, Anna-Sofie; Laserna de Himpsl, Maiti; Ziegelbauer, Kathrin; Laizer, Nassor; Camenzind, Lukas; Di Pasquale, Aurelio; Ekpo, Uwem F.; Simoonga, Christopher; Mushinge, Gabriel; Saarnak, Christopher F. L.; Utzinger, Jürg; Kristensen, Thomas K.; Vounatsou, Penelope
2011-01-01
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 and running of a global NTD database is feasible and should be expanded without delay. PMID:22180793
Hernández-Romieu, Alfonso Claudio; Elnecavé-Olaiz, Alejandro; Huerta-Uribe, Nidia; Reynoso-Noverón, Nancy
2011-01-01
Determine the influence of nutritional counseling, exercise, access to social healthcare and drugs, and the quality of medical care on the control of diabetics. The information and blood samples were obtained in 2005. Glycemic control was defined as good if HbA1c was ≤7.0%, poor from 7.01%-9.50% and very poor if HbA1c >9.5%. Binary logistic regression models were used to determine the association of these factors with HbA1c>9.5%. Thirty percent of the patients with a medical diagnosis of diabetes had adequate metabolic control. Nutritional guidance was associated with an increase in the degree of control. A majority of diabetics have poor or very poor glycemic control. Strengthening the quality of and access to medical care for these patients is urgently needed.
The Modeling of Virtual Environment Distance Education
NASA Astrophysics Data System (ADS)
Xueqin, Chang
This research presented a virtual environment that integrates in a virtual mockup services available in a university campus for students and teachers communication in different actual locations. Advantages of this system include: the remote access to a variety of services and educational tools, the representation of real structures and landscapes in an interactive 3D model that favors localization of services and preserves the administrative organization of the university. For that, the system was implemented a control access for users and an interface to allow the use of previous educational equipments and resources not designed for distance education mode.
Xu, Qian; Tan, Chengxiang; Fan, Zhijie; Zhu, Wenye; Xiao, Ya; Cheng, Fujia
2018-05-17
Nowadays, fog computing provides computation, storage, and application services to end users in the Internet of Things. One of the major concerns in fog computing systems is how fine-grained access control can be imposed. As a logical combination of attribute-based encryption and attribute-based signature, Attribute-based Signcryption (ABSC) can provide confidentiality and anonymous authentication for sensitive data and is more efficient than traditional "encrypt-then-sign" or "sign-then-encrypt" strategy. Thus, ABSC is suitable for fine-grained access control in a semi-trusted cloud environment and is gaining more and more attention recently. However, in many existing ABSC systems, the computation cost required for the end users in signcryption and designcryption is linear with the complexity of signing and encryption access policy. Moreover, only a single authority that is responsible for attribute management and key generation exists in the previous proposed ABSC schemes, whereas in reality, mostly, different authorities monitor different attributes of the user. In this paper, we propose OMDAC-ABSC, a novel data access control scheme based on Ciphertext-Policy ABSC, to provide data confidentiality, fine-grained control, and anonymous authentication in a multi-authority fog computing system. The signcryption and designcryption overhead for the user is significantly reduced by outsourcing the undesirable computation operations to fog nodes. The proposed scheme is proven to be secure in the standard model and can provide attribute revocation and public verifiability. The security analysis, asymptotic complexity comparison, and implementation results indicate that our construction can balance the security goals with practical efficiency in computation.
Jacobs, Jelle; Atkins, Mardelle; Davie, Kristofer; Imrichova, Hana; Romanelli, Lucia; Christiaens, Valerie; Hulselmans, Gert; Potier, Delphine; Wouters, Jasper; Taskiran, Ibrahim I; Paciello, Giulia; González-Blas, Carmen B; Koldere, Duygu; Aibar, Sara; Halder, Georg; Aerts, Stein
2018-06-04
Transcriptional enhancers function as docking platforms for combinations of transcription factors (TFs) to control gene expression. How enhancer sequences determine nucleosome occupancy, TF recruitment and transcriptional activation in vivo remains unclear. Using ATAC-seq across a panel of Drosophila inbred strains, we found that SNPs affecting binding sites of the TF Grainy head (Grh) causally determine the accessibility of epithelial enhancers. We show that deletion and ectopic expression of Grh cause loss and gain of DNA accessibility, respectively. However, although Grh binding is necessary for enhancer accessibility, it is insufficient to activate enhancers. Finally, we show that human Grh homologs-GRHL1, GRHL2 and GRHL3-function similarly. We conclude that Grh binding is necessary and sufficient for the opening of epithelial enhancers but not for their activation. Our data support a model positing that complex spatiotemporal expression patterns are controlled by regulatory hierarchies in which pioneer factors, such as Grh, establish tissue-specific accessible chromatin landscapes upon which other factors can act.
Contact Us About Clearinghouse for Inventories and Emissions Factors
Emissions inventories, modeling, and monitoring are the basis for understanding, controlling and tracking stationary sources of air pollution. This technical site provides access to tools and data to support those efforts.
McGrail, Matthew Richard; Humphreys, John Stirling; Ward, Bernadette
2015-05-29
Poor access to doctors at times of need remains a significant impediment to achieving good health for many rural residents. The two-step floating catchment area (2SFCA) method has emerged as a key tool for measuring healthcare access in rural areas. However, the choice of catchment size, a key component of the 2SFCA method, is problematic because little is known about the distance tolerance of rural residents for health-related travel. Our study sought new evidence to test the hypothesis that residents of sparsely settled rural areas are prepared to travel further than residents of closely settled rural areas when accessing primary health care at times of need. A questionnaire survey of residents in five small rural communities of Victoria and New South Wales in Australia was used. The two outcome measures were current travel time to visit their usual doctor and maximum time prepared to travel to visit a doctor, both for non-emergency care. Kaplan-Meier charts were used to compare the association between increased distance and decreased travel propensity for closely-settled and sparsely-settled areas, and ordinal multivariate regression models tested significance after controlling for health-related travel moderating factors and town clustering. A total of 1079 questionnaires were completed with 363 from residents in closely-settled locations and 716 from residents in sparsely-settled areas. Residents of sparsely-settled communities travel, on average, 10 min further than residents of closely-settled communities (26.3 vs 16.9 min, p < 0.001), though this difference was not significant after controlling for town clustering. Differences were more apparent in terms of maximum time prepared to travel (54.1 vs 31.9 min, p < 0.001). Differences of maximum time remained significant after controlling for demographic and other constraints to access, such as transport availability or difficulties getting doctor appointments, as well as after controlling for town clustering and current travel times. Improved geographical access remains a key issue underpinning health policies designed to improve the provision of rural primary health care services. This study provides empirical evidence that travel behaviour should not be implicitly assumed constant amongst rural populations when modelling access through methods like the 2SFCA.
AEROSAT Access Control Summary
DOT National Transportation Integrated Search
1976-10-01
The report consists of three basic sections. Section 2 is a discussion of the communications concepts germane to AEROSAT access control. It defines and reviews the principles of multiplexing, multiple access, demand access, and access control and rel...
Aerosat Access Control Summary
DOT National Transportation Integrated Search
1976-10-01
The report consists of three basic sections. Section 2 is a discussion of the communications concepts germane to AEROSAT access control. It defines and reviews the principles of multiplexing, multiple access, demand access, and access control and rel...
A Neuroanatomical Model of Prefrontal Inhibitory Modulation of Memory Retrieval
Depue, Brendan E.
2012-01-01
Memory of past experience is essential for guiding goal-related behavior. Being able to control accessibility of memory through modulation of retrieval enables humans to flexibly adapt to their environment. Understanding the specific neural pathways of how this control is achieved has largely eluded cognitive neuroscience. Accordingly, in the current paper I review literature that examines the overt control over retrieval in order to reduce accessibility. I first introduce three hypotheses of inhibition of retrieval. These hypotheses involve: i) attending to other stimuli as a form of diversionary attention, ii) inhibiting the specific individual neural representation of the memory, and iii) inhibiting the hippocampus and retrieval process more generally to prevent reactivation of the representation. I then analyze literature taken from the White Bear Suppression, Directed Forgetting and Think/No-Think tasks to provide evidence for these hypotheses. Finally, a neuroanatomical model is developed to indicate three pathways from PFC to the hippocampal complex that support inhibition of memory retrieval. Describing these neural pathways increases our understanding of control over memory in general. PMID:22374224
Provably Secure Heterogeneous Access Control Scheme for Wireless Body Area Network.
Omala, Anyembe Andrew; Mbandu, Angolo Shem; Mutiria, Kamenyi Domenic; Jin, Chunhua; Li, Fagen
2018-04-28
Wireless body area network (WBAN) provides a medium through which physiological information could be harvested and transmitted to application provider (AP) in real time. Integrating WBAN in a heterogeneous Internet of Things (IoT) ecosystem would enable an AP to monitor patients from anywhere and at anytime. However, the IoT roadmap of interconnected 'Things' is still faced with many challenges. One of the challenges in healthcare is security and privacy of streamed medical data from heterogeneously networked devices. In this paper, we first propose a heterogeneous signcryption scheme where a sender is in a certificateless cryptographic (CLC) environment while a receiver is in identity-based cryptographic (IBC) environment. We then use this scheme to design a heterogeneous access control protocol. Formal security proof for indistinguishability against adaptive chosen ciphertext attack and unforgeability against adaptive chosen message attack in random oracle model is presented. In comparison with some of the existing access control schemes, our scheme has lower computation and communication cost.
Liu, Yanchen; Shi, Hanchang; Shi, Huiming; Wang, Zhiqiang
2010-10-01
The aim of study was proposed a new control model feasible on-line implemented by Programmable Logic Controller (PLC) to enhance nitrogen removal against the fluctuation of influent in Carrousel oxidation ditch. The discrete-time control model was established by confirmation model of operational conditions based on a expert access, which was obtained by a simulation using Activated Sludge Model 2-D (ASM2-D) and Computation Fluid Dynamics (CFD), and discrete-time control model to switch between different operational stages. A full-scale example is provided to demonstrate the feasibility of the proposed operation and the procedure of the control design. The effluent quality was substantially improved, to the extent that it met the new wastewater discharge standards of NH(3)-N<5mg/L and TN<15 mg/L enacted in China throughout a one-day period with fluctuation of influent. Copyright © 2010 Elsevier Ltd. All rights reserved.
A Public-Health-Based Vision for the Management and Regulation of Psychedelics.
Haden, Mark; Emerson, Brian; Tupper, Kenneth W
2016-01-01
The Health Officers Council of British Columbia has proposed post-prohibition regulatory models for currently illegal drugs based on public health principles, and this article continues this work by proposing a model for the regulation and management of psychedelics. This article outlines recent research on psychedelic substances and the key determinants of benefit and harm from their use. It then describes a public-health-based model for the regulation of psychedelics, which includes governance, supervision, set and setting controls, youth access, supply control, demand limitation, and evaluation.
Roberto, Luana Leal; Noronha, Daniele Durães; Souza, Taiane Oliveira; Miranda, Ellen Janayne Primo; Martins, Andréa Maria Eleutério de Barros Lima; Paula, Alfredo Maurício Batista De; Ferreira, Efigênia Ferreira E; Haikal, Desirée Sant'ana
2018-03-01
This study sought to investigate factors associated with the lack of access to information on oral health among adults. It is a cross-sectional study, carried out among 831 adults (35-44 years of age). The dependent variable was access to information on how to avoid oral problems, and the independent variables were gathered into subgroups according to the theoretical model for literacy in health. Binary logistic regression was carried out, and results were corrected by the design effect. It was observed that 37.5% had no access to information about dental problems. The lack of access was higher among adults who had lower per capita income, were dissatisfied with the dental services provided, did not use dental floss, had unsatisfactory physical control of the quality of life, and self-perceived their oral health as fair/poor/very poor. The likelihood of not having access to information about dental problems among those dissatisfied with the dental services used was 3.28 times higher than for those satisfied with the dental services used. Thus, decreased access to information was related to unfavorable conditions among adults. Health services should ensure appropriate information to their users in order to increase health literacy levels and improve satisfaction and equity.
Security in the CernVM File System and the Frontier Distributed Database Caching System
NASA Astrophysics Data System (ADS)
Dykstra, D.; Blomer, J.
2014-06-01
Both the CernVM File System (CVMFS) and the Frontier Distributed Database Caching System (Frontier) distribute centrally updated data worldwide for LHC experiments using http proxy caches. Neither system provides privacy or access control on reading the data, but both control access to updates of the data and can guarantee the authenticity and integrity of the data transferred to clients over the internet. CVMFS has since its early days required digital signatures and secure hashes on all distributed data, and recently Frontier has added X.509-based authenticity and integrity checking. In this paper we detail and compare the security models of CVMFS and Frontier.
Cardea: Dynamic Access Control in Distributed Systems
NASA Technical Reports Server (NTRS)
Lepro, Rebekah
2004-01-01
Modern authorization systems span domains of administration, rely on many different authentication sources, and manage complex attributes as part of the authorization process. This . paper presents Cardea, a distributed system that facilitates dynamic access control, as a valuable piece of an inter-operable authorization framework. First, the authorization model employed in Cardea and its functionality goals are examined. Next, critical features of the system architecture and its handling of the authorization process are then examined. Then the S A M L and XACML standards, as incorporated into the system, are analyzed. Finally, the future directions of this project are outlined and connection points with general components of an authorization system are highlighted.
Anderson, Rachel I; Lopez, Marcelo F; Becker, Howard C
2016-06-01
Stress exposure has been identified as one risk factor for alcohol abuse that may facilitate the transition from social or regulated alcohol use to the development of alcohol dependence. Additionally, stress is a common trigger for relapse and subsequent loss of control of drinking in alcohol-dependent individuals. The present study was designed to characterize effects of repeated forced swim stress (FSS) on ethanol consumption in three rodent drinking models that engender high levels of ethanol consumption. Adult male C57BL/6J mice were exposed to 10-min FSS 4 h prior to each drinking session in three different models of high ethanol consumption: chronic intermittent ethanol (CIE) drinking (a model of dependence-like drinking), drinking-in-the-dark (DID; a model of binge-like drinking), and intermittent vs. continuous access (a model of escalated drinking). In the CIE drinking paradigm, daily FSS facilitated the escalation of ethanol intake that is typically seen in CIE-exposed mice without altering ethanol consumption in control mice exposed to FSS. FSS prior to drinking sessions did not alter ethanol consumption in the DID or intermittent access paradigms, whereas stressed mice in the continuous access procedure consumed less ethanol than their nonstressed counterparts. The CIE drinking paradigm may provide a helpful preclinical model of stress-induced transition to ethanol dependence that can be used to (1) identify underlying neural mechanisms that facilitate this transition and (2) evaluate the therapeutic potential of various pharmacological agents hypothesized to alleviate stress-induced drinking.
Ontology based log content extraction engine for a posteriori security control.
Azkia, Hanieh; Cuppens-Boulahia, Nora; Cuppens, Frédéric; Coatrieux, Gouenou
2012-01-01
In a posteriori access control, users are accountable for actions they performed and must provide evidence, when required by some legal authorities for instance, to prove that these actions were legitimate. Generally, log files contain the needed data to achieve this goal. This logged data can be recorded in several formats; we consider here IHE-ATNA (Integrating the healthcare enterprise-Audit Trail and Node Authentication) as log format. The difficulty lies in extracting useful information regardless of the log format. A posteriori access control frameworks often include a log filtering engine that provides this extraction function. In this paper we define and enforce this function by building an IHE-ATNA based ontology model, which we query using SPARQL, and show how the a posteriori security controls are made effective and easier based on this function.
McCarrier, Kelly P; Martin, Diane P; Ralston, James D; Zimmerman, Frederick J
2010-05-01
Minimum wage policies have been advanced as mechanisms to improve the economic conditions of the working poor. Both positive and negative effects of such policies on health care access have been hypothesized, but associations have yet to be thoroughly tested. To examine whether the presence of minimum wage policies in excess of the federal standard of $5.15 per hour was associated with health care access indicators among low-skilled adults of working age, a cross-sectional analysis of 2004 Behavioral Risk Factor Surveillance System data was conducted. Self-reported health insurance status and experience with cost-related barriers to needed medical care were adjusted in multi-level logistic regression models to control for potential confounding at the state, county, and individual levels. State-level wage policy was not found to be associated with insurance status or unmet medical need in the models, providing early evidence that increased minimum wage rates may neither strengthen nor weaken access to care as previously predicted.
Green, Beverly B; Ralston, James D; Fishman, Paul A; Catz, Sheryl L; Cook, Andrea; Carlson, Jim; Tyll, Lynda; Carrell, David; Thompson, Robert S
2008-05-01
Randomized controlled trials have provided unequivocal evidence that treatment of hypertension decreases mortality and major disability from cardiovascular disease; however, blood pressure remains inadequately treated in most affected individuals. This large gap continues despite the facts that more than 90% of adults with hypertension have health insurance, and hypertension is the leading cause of visits to the doctor. New approaches are needed to improve hypertension care. The Electronic Communications and Home Blood Pressure Monitoring (e-BP) study is a three-arm randomized controlled trial designed to determine whether care based on the Chronic Care Model and delivered over the Internet improves hypertension care. The primary study outcomes are systolic, diastolic, and blood pressure control; secondary outcomes are medication adherence, patient self-efficacy, satisfaction and quality of life, and healthcare utilization and costs. Hypertensive patients receiving care at Group Health medical centers are eligible if they have uncontrolled blood pressure on two screening visits and access to the Web and an e-mail address. Study participants are randomly assigned to three intervention groups: (a) usual care; (b) home blood pressure monitoring receipt and proficiency training on its use and the Group Health secure patient website (with secure e-mail access to their healthcare provider, access to a shared medical record, prescription refill and other services); or (c) this plus pharmacist care management (collaborative care management between the patient, the pharmacist, and the patient's physician via a secure patient website and the electronic medical record). We will determine whether a new model of patient-centered care that leverages Web communications, self-monitoring, and collaborative care management improves hypertension control. If this model proves successful and cost-effective, similar interventions could be used to improve the care of large numbers of patients with uncontrolled hypertension.
Using ICT techniques for improving mechatronic systems' dependability
NASA Astrophysics Data System (ADS)
Miron, Emanuel; Silva, João P. M. A.; Machado, José; Olaru, Dumitru; Prisacaru, Gheorghe
2013-10-01
The use of analysis techniques for industrial controller's analysis, such as Simulation and Formal Verification, is complex on industrial context. This complexity is due to the fact that such techniques require sometimes high investment in specific skilled human resources that have sufficient theoretical knowledge in those domains. This paper aims, mainly, to show that it is possible to obtain a timed automata model for formal verification purposes, considering the CAD model of a mechanical component. This systematic approach can be used, by companies, for the analysis of industrial controllers programs. For this purpose, it is discussed, in the paper, the best way to systematize these procedures, and this paper describes, only, the first step of a complex process and promotes a discussion of the main difficulties that can be found and a possibility for handle those difficulties. A library for formal verification purposes is obtained from original 3D CAD models using Software as a Service platform (SaaS) that, nowadays, has become a common deliverable model for many applications, because SaaS is typically accessed by users via internet access.
Sabino, Valentina; Rice, Kenner C.; Zorrilla, Eric P.
2013-01-01
Positive reinforcement (e.g., appetitive, rewarding properties) has often been hypothesized to maintain excessive intake of palatable foods. Recently, rats receiving intermittent access to high sucrose diets showed binge-like intake with withdrawal-like signs upon cessation of access, suggesting negative reinforcement mechanisms contribute as well. Whether intermittent access to high fat diets also produces withdrawal-like syndromes is controversial. The present study therefore tested the hypothesis that binge-like eating and withdrawal-like anxiety would arise in a novel model of binge eating based on daily 10-min access to a sweet fat diet (35% fat kcal, 31% sucrose kcal). Within 2–3 weeks, female Wistar rats developed binge-like intake comparable to levels seen previously for high sucrose diets (~40% of daily caloric intake within 10 min) plus excess weight gain and adiposity, but absent increased anxiety-like behavior during elevated plus-maze or defensive withdrawal tests after diet withdrawal. Binge-like intake was unaffected by pretreatment with the corticotropin-releasing factor type 1 (CRF1) receptor antagonist R121919, and corticosterone responses to restraint stress did not differ between sweet-fat binge rats and chow-fed controls. In contrast, pretreatment with the cannabinoid type 1 (CB1) receptor antagonist SR147778 dose-dependently reduced binge-like intake, albeit less effectively than in ad lib chow or sweet fat controls. A priming dose of the sweet fat diet did not precipitate increased anxiety-like behavior, but rather increased plus-maze locomotor activity. The results suggest that CB1-dependent positive reinforcement rather than CRF1-dependent negative reinforcement mechanisms predominantly maintain excessive intake in this limited access model of sweet-fat diet binges. PMID:22776620
What we talk about when we talk about access deficits
Mirman, Daniel; Britt, Allison E.
2014-01-01
Semantic impairments have been divided into storage deficits, in which the semantic representations themselves are damaged, and access deficits, in which the representations are intact but access to them is impaired. The behavioural phenomena that have been associated with access deficits include sensitivity to cueing, sensitivity to presentation rate, performance inconsistency, negative serial position effects, sensitivity to number and strength of competitors, semantic blocking effects, disordered selection between strong and weak competitors, correlation between semantic deficits and executive function deficits and reduced word frequency effects. Four general accounts have been proposed for different subsets of these phenomena: abnormal refractoriness, too much activation, impaired competitive selection and deficits of semantic control. A combination of abnormal refractoriness and impaired competitive selection can account for most of the behavioural phenomena, but there remain several open questions. In particular, it remains unclear whether access deficits represent a single syndrome, a syndrome with multiple subtypes or a variable collection of phenomena, whether the underlying deficit is domain-general or domain-specific, whether it is owing to disorders of inhibition, activation or selection, and the nature of the connection (if any) between access phenomena in aphasia and in neurologically intact controls. Computational models offer a promising approach to answering these questions. PMID:24324232
An evidential approach to problem solving when a large number of knowledge systems is available
NASA Technical Reports Server (NTRS)
Dekorvin, Andre
1989-01-01
Some recent problems are no longer formulated in terms of imprecise facts, missing data or inadequate measuring devices. Instead, questions pertaining to knowledge and information itself arise and can be phrased independently of any particular area of knowledge. The problem considered in the present work is how to model a problem solver that is trying to find the answer to some query. The problem solver has access to a large number of knowledge systems that specialize in diverse features. In this context, feature means an indicator of what the possibilities for the answer are. The knowledge systems should not be accessed more than once, in order to have truly independent sources of information. Moreover, these systems are allowed to run in parallel. Since access might be expensive, it is necessary to construct a management policy for accessing these knowledge systems. To help in the access policy, some control knowledge systems are available. Control knowledge systems have knowledge about the performance parameters status of the knowledge systems. In order to carry out the double goal of estimating what units to access and to answer the given query, diverse pieces of evidence must be fused. The Dempster-Shafer Theory of Evidence is used to pool the knowledge bases.
Pearce, J; Hiscock, R; Moon, G; Barnett, R
2009-01-01
To investigate whether neighbourhood measures of geographical accessibility to outlets selling tobacco (supermarkets, convenience stores and petrol stations) are associated with individual smoking behaviour in New Zealand. Using geographical information systems, travel times from the population-weighted centroid of each neighbourhood to the closest outlet selling tobacco were calculated for all 38,350 neighbourhoods across New Zealand. These measures were appended to the 2002/03 New Zealand Health Survey, a national survey of 12, 529 adults. Two-level logistic regression models were fitted to examine the effects of neighbourhood locational access upon individual smoking behaviour after controlling for potential individual- and neighbourhood-level confounding factors, including deprivation and urban/rural status. After controlling for individual-level demographic and socioeconomic variables, individuals living in the quartiles of neighbourhoods with the best access to supermarkets (OR 1.23, 95% CI 1.06 to 1.42) and convenience stores (OR 1.19, 95% CI 1.03 to 1.38) had a higher odds of smoking compared with individuals in the worst access quartiles. However, the association between neighbourhood accessibility to supermarkets and convenience stores was not apparent once other neighbourhood-level variables (deprivation and rurality) were included. At the national level, there is little evidence to suggest that, after adjustment for neighbourhood deprivation, better locational access to tobacco retail provision in New Zealand is associated with individual-level smoking behaviour.
NASA Astrophysics Data System (ADS)
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.
Evolving bipartite authentication graph partitions
Pope, Aaron Scott; Tauritz, Daniel Remy; Kent, Alexander D.
2017-01-16
As large scale enterprise computer networks become more ubiquitous, finding the appropriate balance between user convenience and user access control is an increasingly challenging proposition. Suboptimal partitioning of users’ access and available services contributes to the vulnerability of enterprise networks. Previous edge-cut partitioning methods unduly restrict users’ access to network resources. This paper introduces a novel method of network partitioning superior to the current state-of-the-art which minimizes user impact by providing alternate avenues for access that reduce vulnerability. Networks are modeled as bipartite authentication access graphs and a multi-objective evolutionary algorithm is used to simultaneously minimize the size of largemore » connected components while minimizing overall restrictions on network users. Lastly, results are presented on a real world data set that demonstrate the effectiveness of the introduced method compared to previous naive methods.« less
Evolving bipartite authentication graph partitions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pope, Aaron Scott; Tauritz, Daniel Remy; Kent, Alexander D.
As large scale enterprise computer networks become more ubiquitous, finding the appropriate balance between user convenience and user access control is an increasingly challenging proposition. Suboptimal partitioning of users’ access and available services contributes to the vulnerability of enterprise networks. Previous edge-cut partitioning methods unduly restrict users’ access to network resources. This paper introduces a novel method of network partitioning superior to the current state-of-the-art which minimizes user impact by providing alternate avenues for access that reduce vulnerability. Networks are modeled as bipartite authentication access graphs and a multi-objective evolutionary algorithm is used to simultaneously minimize the size of largemore » connected components while minimizing overall restrictions on network users. Lastly, results are presented on a real world data set that demonstrate the effectiveness of the introduced method compared to previous naive methods.« less
Xu, Qian; Tan, Chengxiang; Fan, Zhijie; Zhu, Wenye; Xiao, Ya; Cheng, Fujia
2018-01-01
Nowadays, fog computing provides computation, storage, and application services to end users in the Internet of Things. One of the major concerns in fog computing systems is how fine-grained access control can be imposed. As a logical combination of attribute-based encryption and attribute-based signature, Attribute-based Signcryption (ABSC) can provide confidentiality and anonymous authentication for sensitive data and is more efficient than traditional “encrypt-then-sign” or “sign-then-encrypt” strategy. Thus, ABSC is suitable for fine-grained access control in a semi-trusted cloud environment and is gaining more and more attention recently. However, in many existing ABSC systems, the computation cost required for the end users in signcryption and designcryption is linear with the complexity of signing and encryption access policy. Moreover, only a single authority that is responsible for attribute management and key generation exists in the previous proposed ABSC schemes, whereas in reality, mostly, different authorities monitor different attributes of the user. In this paper, we propose OMDAC-ABSC, a novel data access control scheme based on Ciphertext-Policy ABSC, to provide data confidentiality, fine-grained control, and anonymous authentication in a multi-authority fog computing system. The signcryption and designcryption overhead for the user is significantly reduced by outsourcing the undesirable computation operations to fog nodes. The proposed scheme is proven to be secure in the standard model and can provide attribute revocation and public verifiability. The security analysis, asymptotic complexity comparison, and implementation results indicate that our construction can balance the security goals with practical efficiency in computation. PMID:29772840
Cardea: Providing Support for Dynamic Resource Access in a Distributed Computing Environment
NASA Technical Reports Server (NTRS)
Lepro, Rebekah
2003-01-01
The environment framing the modem authorization process span domains of administration, relies on many different authentication sources, and manages complex attributes as part of the authorization process. Cardea facilitates dynamic access control within this environment as a central function of an inter-operable authorization framework. The system departs from the traditional authorization model by separating the authentication and authorization processes, distributing the responsibility for authorization data and allowing collaborating domains to retain control over their implementation mechanisms. Critical features of the system architecture and its handling of the authorization process differentiate the system from existing authorization components by addressing common needs not adequately addressed by existing systems. Continuing system research seeks to enhance the implementation of the current authorization model employed in Cardea, increase the robustness of current features, further the framework for establishing trust and promote interoperability with existing security mechanisms.
NASA Technical Reports Server (NTRS)
2002-01-01
Ames Research Center granted Reality Capture Technologies (RCT), Inc., a license to further develop NASA's Mars Map software platform. The company incorporated NASA#s innovation into software that uses the Virtual Plant Model (VPM)(TM) to structure, modify, and implement the construction sites of industrial facilities, as well as develop, validate, and train operators on procedures. The VPM orchestrates the exchange of information between engineering, production, and business transaction systems. This enables users to simulate, control, and optimize work processes while increasing the reliability of critical business decisions. Engineers can complete the construction process and test various aspects of it in virtual reality before building the actual structure. With virtual access to and simulation of the construction site, project personnel can manage, access control, and respond to changes on complex constructions more effectively. Engineers can also create operating procedures, training, and documentation. Virtual Plant Model(TM) is a trademark of Reality Capture Technologies, Inc.
Levy, David T; Ross, Hana; Zaloshnja, Eduard; Shuperka, Roland; Rusta, Meriglena
2008-12-01
The Albania SimSmoke simulation model is used to examine the effects of tobacco control policies. The model is used to consider the projected trends in smoking prevalence and associated smoking-attributable deaths in the absence of new policies, and then to examine the effect of new policies that are consistent with the Framework Convention for Tobacco Control (FCTC) on these outcomes. The model shows that significant inroads to reducing smoking prevalence and premature mortality can be achieved through tax increases. Acomprehensive strategy to further reduce smoking rates should include a media campaign complete with programs to publicize and enforce clean air laws, a comprehensive cessation treatment program, strong health warnings, advertising bans, and youth access laws. Besides presenting the benefits of a comprehensive tobacco control strategy, the model helps to identify important information needed for both modeling and policymaking. The effectiveness of future tobacco control policy will require proper surveillance and evaluation schemes for Albania.
Access control based on attribute certificates for medical intranet applications.
Mavridis, I; Georgiadis, C; Pangalos, G; Khair, M
2001-01-01
Clinical information systems frequently use intranet and Internet technologies. However these technologies have emphasized sharing and not security, despite the sensitive and private nature of much health information. Digital certificates (electronic documents which recognize an entity or its attributes) can be used to control access in clinical intranet applications. To outline the need for access control in distributed clinical database systems, to describe the use of digital certificates and security policies, and to propose the architecture for a system using digital certificates, cryptography and security policy to control access to clinical intranet applications. We have previously developed a security policy, DIMEDAC (Distributed Medical Database Access Control), which is compatible with emerging public key and privilege management infrastructure. In our implementation approach we propose the use of digital certificates, to be used in conjunction with DIMEDAC. Our proposed access control system consists of two phases: the ways users gain their security credentials; and how these credentials are used to access medical data. Three types of digital certificates are used: identity certificates for authentication; attribute certificates for authorization; and access-rule certificates for propagation of access control policy. Once a user is identified and authenticated, subsequent access decisions are based on a combination of identity and attribute certificates, with access-rule certificates providing the policy framework. Access control in clinical intranet applications can be successfully and securely managed through the use of digital certificates and the DIMEDAC security policy.
Energy-efficient boarder node medium access control protocol for wireless sensor networks.
Razaque, Abdul; Elleithy, Khaled M
2014-03-12
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-synchronous feature with a low duty cycle, which is advantageous for reducing the latency and energy consumption for several WSN application areas to improve the throughput. BN-MAC uses a unique window slot size to enhance the contention resolution issue for improved throughput. BN-MAC also prefers to communicate within a one-hop destination using Anycast, which maintains load balancing to maintain network reliability. BN-MAC is introduced with the goal of supporting four major application areas: monitoring and behavioral areas, controlling natural disasters, human-centric applications, and tracking mobility and static home automation devices from remote places. These application areas require a congestion-free mobility-supported MAC protocol to guarantee reliable data delivery. BN-MAC was evaluated using network simulator-2 (ns2) and compared with other hybrid MAC protocols, such as Zebra medium access control (Z-MAC), advertisement-based MAC (A-MAC), Speck-MAC, adaptive duty cycle SMAC (ADC-SMAC), and low-power real-time medium access control (LPR-MAC). The simulation results indicate that BN-MAC is a robust and energy-efficient protocol that outperforms other hybrid MAC protocols in the context of quality of service (QoS) parameters, such as energy consumption, latency, throughput, channel access time, successful delivery rate, coverage efficiency, and average duty cycle.
Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks
Razaque, Abdul; 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, 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-synchronous feature with a low duty cycle, which is advantageous for reducing the latency and energy consumption for several WSN application areas to improve the throughput. BN-MAC uses a unique window slot size to enhance the contention resolution issue for improved throughput. BN-MAC also prefers to communicate within a one-hop destination using Anycast, which maintains load balancing to maintain network reliability. BN-MAC is introduced with the goal of supporting four major application areas: monitoring and behavioral areas, controlling natural disasters, human-centric applications, and tracking mobility and static home automation devices from remote places. These application areas require a congestion-free mobility-supported MAC protocol to guarantee reliable data delivery. BN-MAC was evaluated using network simulator-2 (ns2) and compared with other hybrid MAC protocols, such as Zebra medium access control (Z-MAC), advertisement-based MAC (A-MAC), Speck-MAC, adaptive duty cycle SMAC (ADC-SMAC), and low-power real-time medium access control (LPR-MAC). The simulation results indicate that BN-MAC is a robust and energy-efficient protocol that outperforms other hybrid MAC protocols in the context of quality of service (QoS) parameters, such as energy consumption, latency, throughput, channel access time, successful delivery rate, coverage efficiency, and average duty cycle. PMID:24625737
GEOSS AIP-2 Climate Change and Biodiversity Use Scenarios: Interoperability Infrastructures
NASA Astrophysics Data System (ADS)
Nativi, Stefano; Santoro, Mattia
2010-05-01
In the last years, scientific community is producing great efforts in order to study the effects of climate change on life on Earth. In this general framework, a key role is played by the impact of climate change on biodiversity. To assess this, several use scenarios require the modeling of climatological change impact on the regional distribution of biodiversity species. Designing and developing interoperability infrastructures which enable scientists to search, discover, access and use multi-disciplinary resources (i.e. datasets, services, models, etc.) is currently one of the main research fields for the Earth and Space Science Informatics. This presentation introduces and discusses an interoperability infrastructure which implements the discovery, access, and chaining of loosely-coupled resources in the climatology and biodiversity domains. This allows to set up and run forecast and processing models. The presented framework was successfully developed and experimented in the context of GEOSS AIP-2 (Global Earth Observation System of Systems, Architecture Implementation Pilot- Phase 2) Climate Change & Biodiversity thematic Working Group. This interoperability infrastructure is comprised of the following main components and services: a)GEO Portal: through this component end user is able to search, find and access the needed services for the scenario execution; b)Graphical User Interface (GUI): this component provides user interaction functionalities. It controls the workflow manager to perform the required operations for the scenario implementation; c)Use Scenario controller: this component acts as a workflow controller implementing the scenario business process -i.e. a typical climate change & biodiversity projection scenario; d)Service Broker implementing Mediation Services: this component realizes a distributed catalogue which federates several discovery and access components (exposing them through a unique CSW standard interface). Federated components publish climate, environmental and biodiversity datasets; e)Ecological Niche Model Server: this component is able to run one or more Ecological Niche Models (ENM) on selected biodiversity and climate datasets; f)Data Access Transaction server: this component publishes the model outputs. This framework was assessed in two use scenarios of GEOSS AIP-2 Climate Change and Biodiversity WG. Both scenarios concern the prediction of species distributions driven by climatological change forecasts. The first scenario dealt with the Pikas specie regional distribution in the Great Basin area (North America). While, the second one concerned the modeling of the Arctic Food Chain species in the North Pole area -the relationships between different environmental parameters and Polar Bears distribution was analyzed. The scientific patronage was provided by the University of Colorado and the University of Alaska, respectively. Results are published in the GEOSS AIP-2 web site: http://www.ogcnetwork.net/AIP2develop.
Ground control station software design for micro aerial vehicles
NASA Astrophysics Data System (ADS)
Walendziuk, Wojciech; Oldziej, Daniel; Binczyk, Dawid Przemyslaw; Slowik, Maciej
2017-08-01
This article describes the process of designing the equipment part and the software of a ground control station used for configuring and operating micro unmanned aerial vehicles (UAV). All the works were conducted on a quadrocopter model being a commonly accessible commercial construction. This article contains a characteristics of the research object, the basics of operating the micro aerial vehicles (MAV) and presents components of the ground control station model. It also describes the communication standards for the purpose of building a model of the station. Further part of the work concerns the software of the product - the GIMSO application (Generally Interactive Station for Mobile Objects), which enables the user to manage the actions and communication and control processes from the UAV. The process of creating the software and the field tests of a station model are also presented in the article.
Allam, Ahmed; Kostova, Zlatina; Nakamoto, Kent; Schulz, Peter Johannes
2015-01-09
Rheumatoid arthritis (RA) is chronic systematic disease that affects people during the most productive period of their lives. Web-based health interventions have been effective in many studies; however, there is little evidence and few studies showing the effectiveness of online social support and especially gamification on patients' behavioral and health outcomes. The aim of this study was to look into the effects of a Web-based intervention that included online social support features and gamification on physical activity, health care utilization, medication overuse, empowerment, and RA knowledge of RA patients. The effect of gamification on website use was also investigated. We conducted a 5-arm parallel randomized controlled trial for RA patients in Ticino (Italian-speaking part of Switzerland). A total of 157 patients were recruited through brochures left with physicians and were randomly allocated to 1 of 4 experimental conditions with different types of access to online social support and gamification features and a control group that had no access to the website. Data were collected at 3 time points through questionnaires at baseline, posttest 2 months later, and at follow-up after another 2 months. Primary outcomes were physical activity, health care utilization, and medication overuse; secondary outcomes included empowerment and RA knowledge. All outcomes were self-reported. Intention-to-treat analysis was followed and multilevel linear mixed models were used to study the change of outcomes over time. The best-fit multilevel models (growth curve models) that described the change in the primary outcomes over the course of the intervention included time and empowerment as time-variant predictors. The growth curve analyses of experimental conditions were compared to the control group. Physical activity increased over time for patients having access to social support sections plus gaming (unstandardized beta coefficient [B]=3.39, P=.02). Health care utilization showed a significant decrease for patients accessing social support features (B=-0.41, P=.01) and patients accessing both social support features and gaming (B=-0.33, P=.03). Patients who had access to either social support sections or the gaming experience of the website gained more empowerment (B=2.59, P=.03; B=2.29, P=.05; respectively). Patients who were offered a gamified experience used the website more often than the ones without gaming (t91=-2.41, P=.02; U=812, P=.02). The Web-based intervention had a positive impact (more desirable outcomes) on intervention groups compared to the control group. Social support sections on the website decreased health care utilization and medication overuse and increased empowerment. Gamification alone or with social support increased physical activity and empowerment and decreased health care utilization. This study provides evidence demonstrating the potential positive effect of gamification and online social support on health and behavioral outcomes. International Standard Randomized Controlled Trial Number (ISRCTN): 57366516; http://www.controlled-trials. com/ISRCTN57366516 (Archived by webcite at http://www.webcitation.org/6PBvvAvvV).
Kostova, Zlatina; Nakamoto, Kent; Schulz, Peter Johannes
2015-01-01
Background Rheumatoid arthritis (RA) is chronic systematic disease that affects people during the most productive period of their lives. Web-based health interventions have been effective in many studies; however, there is little evidence and few studies showing the effectiveness of online social support and especially gamification on patients’ behavioral and health outcomes. Objective The aim of this study was to look into the effects of a Web-based intervention that included online social support features and gamification on physical activity, health care utilization, medication overuse, empowerment, and RA knowledge of RA patients. The effect of gamification on website use was also investigated. Methods We conducted a 5-arm parallel randomized controlled trial for RA patients in Ticino (Italian-speaking part of Switzerland). A total of 157 patients were recruited through brochures left with physicians and were randomly allocated to 1 of 4 experimental conditions with different types of access to online social support and gamification features and a control group that had no access to the website. Data were collected at 3 time points through questionnaires at baseline, posttest 2 months later, and at follow-up after another 2 months. Primary outcomes were physical activity, health care utilization, and medication overuse; secondary outcomes included empowerment and RA knowledge. All outcomes were self-reported. Intention-to-treat analysis was followed and multilevel linear mixed models were used to study the change of outcomes over time. Results The best-fit multilevel models (growth curve models) that described the change in the primary outcomes over the course of the intervention included time and empowerment as time-variant predictors. The growth curve analyses of experimental conditions were compared to the control group. Physical activity increased over time for patients having access to social support sections plus gaming (unstandardized beta coefficient [B]=3.39, P=.02). Health care utilization showed a significant decrease for patients accessing social support features (B=–0.41, P=.01) and patients accessing both social support features and gaming (B=–0.33, P=.03). Patients who had access to either social support sections or the gaming experience of the website gained more empowerment (B=2.59, P=.03; B=2.29, P=.05; respectively). Patients who were offered a gamified experience used the website more often than the ones without gaming (t 91=–2.41, P=.02; U=812, P=.02). Conclusions The Web-based intervention had a positive impact (more desirable outcomes) on intervention groups compared to the control group. Social support sections on the website decreased health care utilization and medication overuse and increased empowerment. Gamification alone or with social support increased physical activity and empowerment and decreased health care utilization. This study provides evidence demonstrating the potential positive effect of gamification and online social support on health and behavioral outcomes. Trial Registration International Standard Randomized Controlled Trial Number (ISRCTN): 57366516; http://www.controlled-trials. com/ISRCTN57366516 (Archived by webcite at http://www.webcitation.org/6PBvvAvvV). PMID:25574939
Leveraging Open Standard Interfaces in Accessing and Processing NASA Data Model Outputs
NASA Astrophysics Data System (ADS)
Falke, S. R.; Alameh, N. S.; Hoijarvi, K.; de La Beaujardiere, J.; Bambacus, M. J.
2006-12-01
An objective of NASA's Earth Science Division is to develop advanced information technologies for processing, archiving, accessing, visualizing, and communicating Earth Science data. To this end, NASA and other federal agencies have collaborated with the Open Geospatial Consortium (OGC) to research, develop, and test interoperability specifications within projects and testbeds benefiting the government, industry, and the public. This paper summarizes the results of a recent effort under the auspices of the OGC Web Services testbed phase 4 (OWS-4) to explore standardization approaches for accessing and processing the outputs of NASA models of physical phenomena. Within the OWS-4 context, experiments were designed to leverage the emerging OGC Web Processing Service (WPS) and Web Coverage Service (WCS) specifications to access, filter and manipulate the outputs of the NASA Goddard Earth Observing System (GEOS) and Goddard Chemistry Aerosol Radiation and Transport (GOCART) forecast models. In OWS-4, the intent is to provide the users with more control over the subsets of data that they can extract from the model results as well as over the final portrayal of that data. To meet that goal, experiments have been designed to test the suitability of use of OGC's Web Processing Service (WPS) and Web Coverage Service (WCS) for filtering, processing and portraying the model results (including slices by height or by time), and to identify any enhancements to the specs to meet the desired objectives. This paper summarizes the findings of the experiments highlighting the value of the Web Processing Service in providing standard interfaces for accessing and manipulating model data within spatial and temporal frameworks. The paper also points out the key shortcomings of the WPS especially in terms in comparison with a SOAP/WSDL approach towards solving the same problem.
75 FR 71790 - Second Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-24
... Committee 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held December 9, 2010...
75 FR 80886 - Third Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-23
... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held January 13, 2011...
76 FR 9632 - Fifth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-18
... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held March 10, 2011, from...
76 FR 3931 - Fourth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-21
... Committee 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 Meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held February 8, 2011...
10 CFR 36.23 - Access control.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 1 2011-01-01 2011-01-01 false Access control. 36.23 Section 36.23 Energy NUCLEAR... Requirements for Irradiators § 36.23 Access control. (a) Each entrance to a radiation room at a panoramic... radiation room at a panoramic irradiator must have an independent backup access control to detect personnel...
10 CFR 36.23 - Access control.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 1 2013-01-01 2013-01-01 false Access control. 36.23 Section 36.23 Energy NUCLEAR... Requirements for Irradiators § 36.23 Access control. (a) Each entrance to a radiation room at a panoramic... radiation room at a panoramic irradiator must have an independent backup access control to detect personnel...
10 CFR 36.23 - Access control.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 1 2012-01-01 2012-01-01 false Access control. 36.23 Section 36.23 Energy NUCLEAR... Requirements for Irradiators § 36.23 Access control. (a) Each entrance to a radiation room at a panoramic... radiation room at a panoramic irradiator must have an independent backup access control to detect personnel...
75 FR 61819 - First Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-06
... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems. DATES: The meeting will be held November 2, 2010...
76 FR 16470 - Sixth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-23
... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to... Committee 224: Airport Security Access Control Systems DATES: The meeting will be held April 13, 2011, from...
75 FR 4007 - Risk Management Controls for Brokers or Dealers With Market Access
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-26
... 3235-AK53 Risk Management Controls for Brokers or Dealers With Market Access AGENCY: Securities and... or other persons, to implement risk management controls and supervisory procedures reasonably... access may not utilize any pre-trade risk management controls (i.e., ``unfiltered'' or ``naked'' access...
Extended TAM Model: Impacts of Convenience on Acceptance and Use of Moodle
ERIC Educational Resources Information Center
Hsu, Hsiao-hui; Chang, Yu-ying
2013-01-01
The increasing online access to courses, programs, and information has shifted the control and responsibility of learning process from instructors to learners. Learners' perceptions of and attitudes toward e-learning constitute a critical factor to the success of such system. The purpose of this study is to take TAM (technology acceptance model)…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-25
... because they control the primary means of access to end users. Although their business models may differ... must understand and respond to these varying business models and pricing disciplines in order to... Commission's Public Reference Room, 100 F Street, NE., Washington, DC 20549, on official business days...
A Security Framework for Online Distance Learning and Training.
ERIC Educational Resources Information Center
Furnell, S. M.; Onions, P. D.; Bleimann, U.; Gojny, U.; Knahl, M.; Roder, H. F.; Sanders, P. W.
1998-01-01
Presents a generic reference model for online distance learning and discusses security issues for each stage (enrollment, study, completion, termination, suspension). Discusses a security framework (authentication and accountability, access control, intrusion detection, network communications, nonrepudiation, learning resources provider…
Arrays of individually controlled ions suitable for two-dimensional quantum simulations
Mielenz, Manuel; Kalis, Henning; Wittemer, Matthias; Hakelberg, Frederick; Warring, Ulrich; Schmied, Roman; Blain, Matthew; Maunz, Peter; Moehring, David L.; Leibfried, Dietrich; Schaetz, Tobias
2016-01-01
A precisely controlled quantum system may reveal a fundamental understanding of another, less accessible system of interest. A universal quantum computer is currently out of reach, but an analogue quantum simulator that makes relevant observables, interactions and states of a quantum model accessible could permit insight into complex dynamics. Several platforms have been suggested and proof-of-principle experiments have been conducted. Here, we operate two-dimensional arrays of three trapped ions in individually controlled harmonic wells forming equilateral triangles with side lengths 40 and 80 μm. In our approach, which is scalable to arbitrary two-dimensional lattices, we demonstrate individual control of the electronic and motional degrees of freedom, preparation of a fiducial initial state with ion motion close to the ground state, as well as a tuning of couplings between ions within experimental sequences. Our work paves the way towards a quantum simulator of two-dimensional systems designed at will. PMID:27291425
Access Control based on Attribute Certificates for Medical Intranet Applications
Georgiadis, Christos; Pangalos, George; Khair, Marie
2001-01-01
Background Clinical information systems frequently use intranet and Internet technologies. However these technologies have emphasized sharing and not security, despite the sensitive and private nature of much health information. Digital certificates (electronic documents which recognize an entity or its attributes) can be used to control access in clinical intranet applications. Objectives To outline the need for access control in distributed clinical database systems, to describe the use of digital certificates and security policies, and to propose the architecture for a system using digital certificates, cryptography and security policy to control access to clinical intranet applications. Methods We have previously developed a security policy, DIMEDAC (Distributed Medical Database Access Control), which is compatible with emerging public key and privilege management infrastructure. In our implementation approach we propose the use of digital certificates, to be used in conjunction with DIMEDAC. Results Our proposed access control system consists of two phases: the ways users gain their security credentials; and how these credentials are used to access medical data. Three types of digital certificates are used: identity certificates for authentication; attribute certificates for authorization; and access-rule certificates for propagation of access control policy. Once a user is identified and authenticated, subsequent access decisions are based on a combination of identity and attribute certificates, with access-rule certificates providing the policy framework. Conclusions Access control in clinical intranet applications can be successfully and securely managed through the use of digital certificates and the DIMEDAC security policy. PMID:11720951
Nagelhout, Gera E; Levy, David T; Blackman, Kenneth; Currie, Laura; Clancy, Luke; Willemsen, Marc C
2012-02-01
To develop a simulation model projecting the effect of tobacco control policies in the Netherlands on smoking prevalence and smoking-attributable deaths. Netherlands SimSmoke-an adapted version of the SimSmoke simulation model of tobacco control policy-uses population, smoking rates and tobacco control policy data for the Netherlands to predict the effect of seven types of policies: taxes, smoke-free legislation, mass media, advertising bans, health warnings, cessation treatment and youth access policies. Outcome measures were smoking prevalence and smoking-attributable deaths. With a comprehensive set of policies, as recommended by MPOWER, smoking prevalence can be decreased by as much as 21% in the first year, increasing to a 35% reduction in the next 20 years and almost 40% by 30 years. By 2040, 7706 deaths can be averted in that year alone with the stronger set of policies. Without effective tobacco control policies, almost a million lives will be lost to tobacco-related diseases between 2011 and 2040. Of those, 145,000 can be saved with a comprehensive tobacco control package. Smoking prevalence and smoking-attributable deaths in the Netherlands can be reduced substantially through tax increases, smoke-free legislation, high-intensity media campaigns, stronger advertising bans and health warnings, comprehensive cessation treatment and youth access laws. The implementation of these FCTC/MPOWER recommended policies could be expected to show similar or even larger relative reductions in smoking prevalence in other countries which currently have weak policies. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.
Sucurovic, Snezana; Milutinovic, Veljko
2008-01-01
The Internet based distributed large scale information systems implements attribute based access control (ABAC) rather than Role Based Access Control (RBAC). The reason is that the Internet is identity less and that ABAC scales better. EXtensible Access Control Markup Language is standardized language for writing access control policies, access control requests and access control responses in ABAC. XACML can provide decentralized administration and credentials distribution. In year 2002 version of CEN ENV 13 606 attributes have been attached to EHCR components and in such a system ABAC and XACML have been easy to implement. This paper presents writing XACML policies in the case when attributes are in hierarchical structure. It is presented two possible solutions to write XACML policy in that case and that the solution when set functions are used is more compact and provides 10% better performances.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-30
... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the seventeenth meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-24
... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty-second meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...
78 FR 7850 - Nineteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-04
... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the nineteenth meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-12
... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty first meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-30
... Committee 224, Airport Security Access Control Systems. AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the thirteenth meeting of RTCA Special Committee 224, Airport Security Access Control Systems DATES: The meeting will be...
77 FR 15448 - Twelfth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-15
... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twelfth meeting of RTCA Special Committee 224, Airport Security Access Control Systems DATES: The meeting will be...
Healthcare teams over the Internet: towards a certificate-based approach.
Georgiadis, Christos K; Mavridis, Ioannis K; Pangalos, George I
2002-01-01
Healthcare environments are a representative case of collaborative environments since individuals (e.g. doctors) in many cases collaborate in order to provide care to patients in a more proficient way. At the same time modem healthcare institutions are increasingly interested in sharing access of their information resources in the networked environment. Healthcare applications over the Internet offer an attractive communication infrastructure at worldwide level but with a noticeably great factor of risk. Security has therefore become a major concern for healthcare applications over the Internet. However, although an adequate level of security can be relied upon digital certificates, if an appropriate security policy is used, additional security considerations are needed in order to deal efficiently with the above team-work concerns. The already known Hybrid Access Control security model supports and handles efficiently healthcare teams with active security capabilities and is capable to exploit the benefits of certificate technology. In this paper we present the way for encoding the appropriate authoritative information in various types of certificates, as well as the overall operational architecture of the implemented access control system for healthcare collaborative environments over the Internet. A pilot implementation of the proposed methodology in a major Greek hospital has shown the applicability of the proposals and the flexibility of the access control provided.
Virtual memory support for distributed computing environments using a shared data object model
NASA Astrophysics Data System (ADS)
Huang, F.; Bacon, J.; Mapp, G.
1995-12-01
Conventional storage management systems provide one interface for accessing memory segments and another for accessing secondary storage objects. This hinders application programming and affects overall system performance due to mandatory data copying and user/kernel boundary crossings, which in the microkernel case may involve context switches. Memory-mapping techniques may be used to provide programmers with a unified view of the storage system. This paper extends such techniques to support a shared data object model for distributed computing environments in which good support for coherence and synchronization is essential. The approach is based on a microkernel, typed memory objects, and integrated coherence control. A microkernel architecture is used to support multiple coherence protocols and the addition of new protocols. Memory objects are typed and applications can choose the most suitable protocols for different types of object to avoid protocol mismatch. Low-level coherence control is integrated with high-level concurrency control so that the number of messages required to maintain memory coherence is reduced and system-wide synchronization is realized without severely impacting the system performance. These features together contribute a novel approach to the support for flexible coherence under application control.
Remote access and operation of telescopes by the scientific users
NASA Astrophysics Data System (ADS)
Edwards, P. G.; Amy, S.; Brodrick, D.; Carretti, E.; Hoyle, S.; Indermuehle, B.; McConnell, D.; Mader, S.; Mirtschin, P.; Preisig, B.; Smith, M.; Stevens, J.; Wark, R.; Wieringa, M.; Wu, X.
2014-08-01
The Australia Telescope National Facility operates three radio telescopes: the Parkes 64m Telescope, the Australia Telescope Compact Array (ATCA), and the Mopra 22m Telescope. Scientific operation of all these is conducted by members of the investigating teams rather than by professional operators. All three can now be accessed and controlled from any location served by the internet, the telescopes themselves being unattended for part or all of the time. Here we describe the rationale, advantages, and means of implementing this operational model.
2011-06-01
event simulation is used to model three alternatives to the ECP system. The baseline system which contains two manned kiosks, a fully automated system...experience is traffic delays in the morning for government employees accessing the bases. If one or two lanes were dedicated to 3 completely or even semi...purpose of clarity, the figure below displays only the two lowest levels of functions. This final functional decomposition identifies the sub functions
2013-06-01
Accessed 20 December 2009. _____. Law No. 5371 of December 5, 1967. DOU, Rio de Janeiro , 06 dez.1967. _____. Decree 6764 of 10 February 2009. DOU... Rio de Janeiro , 11 Feb 2009. IBAMA. Ibama.gov.br, 2013. Available in: - http://www.ibama.gov.br/acesso-a- informacao/institucional. Accessed...1971. DAMATTA, R. The house and the street. 5th. ed. Rio de Janeiro : [S.N.], 1997. BROOK, D. The Brazilian people. 6th. ed. Sao Paulo
Distributed Fair Auto Rate Medium Access Control for IEEE 802.11 Based WLANs
NASA Astrophysics Data System (ADS)
Zhu, Yanfeng; Niu, Zhisheng
Much research has shown that a carefully designed auto rate medium access control can utilize the underlying physical multi-rate capability to exploit the time-variation of the channel. In this paper, we develop a simple analytical model to elucidate the rule that maximizes the throughput of RTS/CTS based multi-rate wireless local area networks. Based on the discovered rule, we propose two distributed fair auto rate medium access control schemes called FARM and FARM+ from the view-point of throughput fairness and time-share fairness, respectively. With the proposed schemes, after receiving a RTS frame, the receiver selectively returns the CTS frame to inform the transmitter the maximum feasible rate probed by the signal-to-noise ratio of the received RTS frame. The key feature of the proposed schemes is that they are capable of maintaining throughput/time-share fairness in asymmetric situation where the distribution of SNR varies with stations. Extensive simulation results show that the proposed schemes outperform the existing throughput/time-share fair auto rate schemes in time-varying channel conditions.
Why build limited access highways?.
DOT National Transportation Integrated Search
1991-01-01
This report first explains what a limited access highway is, then describes the benefits and advantages of limited access highways. As compared with highways with no control of access, limited access highways (especially those with full control) have...
Towards an Approach of Semantic Access Control for Cloud Computing
NASA Astrophysics Data System (ADS)
Hu, Luokai; Ying, Shi; Jia, Xiangyang; Zhao, Kai
With the development of cloud computing, the mutual understandability among distributed Access Control Policies (ACPs) has become an important issue in the security field of cloud computing. Semantic Web technology provides the solution to semantic interoperability of heterogeneous applications. In this paper, we analysis existing access control methods and present a new Semantic Access Control Policy Language (SACPL) for describing ACPs in cloud computing environment. Access Control Oriented Ontology System (ACOOS) is designed as the semantic basis of SACPL. Ontology-based SACPL language can effectively solve the interoperability issue of distributed ACPs. This study enriches the research that the semantic web technology is applied in the field of security, and provides a new way of thinking of access control in cloud computing.
Putting FLEXPART to REST: The Provision of Atmospheric Transport Modeling Services
NASA Astrophysics Data System (ADS)
Morton, Don; Arnold, Dèlia
2015-04-01
We are developing a RESTful set of modeling services for the FLEXPART modeling system. FLEXPART (FLEXible PARTicle dispersion model) is a Lagrangian transport and dispersion model used by a growing international community. It has been used to simulate and forecast the atmospheric transport of wildfire smoke, volcanic ash and radionuclides and may be run in backwards mode to provide information for the determination of emission sources such as nuclear emissions and greenhouse gases. This open source software is distributed in source code form, and has several compiler and library dependencies that users need to address. Although well-documented, getting it compiled, set up, running, and post-processed is often tedious, making it difficult for the inexperienced or casual user. Well-designed modeling services lower the entry barrier for scientists to perform simulations, allowing them to create and execute their models from a variety of devices and programming environments. This world of Service Oriented Architectures (SOA) has progressed to a REpresentational State Transfer (REST) paradigm, in which the pervasive and mature HTTP environment is used as a foundation for providing access to model services. With such an approach, sound software engineering practises are adhered to in order to deploy service modules exhibiting very loose coupling with the clients. In short, services are accessed and controlled through the formation of properly-constructed Uniform Resource Identifiers (URI's), processed in an HTTP environment. In this way, any client or combination of clients - whether a bash script, Python program, web GUI, or even Unix command line - that can interact with an HTTP server, can run the modeling environment. This loose coupling allows for the deployment of a variety of front ends, all accessing a common modeling backend system. Furthermore, it is generally accepted in the cloud computing community that RESTful approaches constitute a sound approach towards successful deployment of services. Through the design of a RESTful, cloud-based modeling system, we provide the ubiquitous access to FLEXPART that allows scientists to focus on modeling processes instead of tedious computational details. In this work, we describe the modeling services environment, and provide examples of access via command-line, Python programs, and web GUI interfaces.
NASA Technical Reports Server (NTRS)
Wilson, William C.
1999-01-01
The NASA Langley Research Center's Wind Tunnel Reinvestment project plans to shrink the existing data acquisition electronics to fit inside a wind tunnel model. Space limitations within a model necessitate a distributed system of Application Specific Integrated Circuits (ASICs) rather than a centralized system based on PC boards. This thesis will focus on the design of the prototype of the communication Controller board. A portion of the communication Controller board is to be used as the basis of an ASIC design. The communication Controller board will communicate between the internal model modules and the external data acquisition computer. This board is based around an Field Programmable Gate Array (FPGA), to allow for reconfigurability. In addition to the FPGA, this board contains buffer Random Access Memory (RAM), configuration memory (EEPROM), drivers for the communications ports, and passive components.
Linear Time Algorithms to Restrict Insider Access using Multi-Policy Access Control Systems
Mell, Peter; Shook, James; Harang, Richard; Gavrila, Serban
2017-01-01
An important way to limit malicious insiders from distributing sensitive information is to as tightly as possible limit their access to information. This has always been the goal of access control mechanisms, but individual approaches have been shown to be inadequate. Ensemble approaches of multiple methods instantiated simultaneously have been shown to more tightly restrict access, but approaches to do so have had limited scalability (resulting in exponential calculations in some cases). In this work, we take the Next Generation Access Control (NGAC) approach standardized by the American National Standards Institute (ANSI) and demonstrate its scalability. The existing publicly available reference implementations all use cubic algorithms and thus NGAC was widely viewed as not scalable. The primary NGAC reference implementation took, for example, several minutes to simply display the set of files accessible to a user on a moderately sized system. In our approach, we take these cubic algorithms and make them linear. We do this by reformulating the set theoretic approach of the NGAC standard into a graph theoretic approach and then apply standard graph algorithms. We thus can answer important access control decision questions (e.g., which files are available to a user and which users can access a file) using linear time graph algorithms. We also provide a default linear time mechanism to visualize and review user access rights for an ensemble of access control mechanisms. Our visualization appears to be a simple file directory hierarchy but in reality is an automatically generated structure abstracted from the underlying access control graph that works with any set of simultaneously instantiated access control policies. It also provide an implicit mechanism for symbolic linking that provides a powerful access capability. Our work thus provides the first efficient implementation of NGAC while enabling user privilege review through a novel visualization approach. This may help transition from concept to reality the idea of using ensembles of simultaneously instantiated access control methodologies, thereby limiting insider threat. PMID:28758045
A User-Centered Approach to Adaptive Hypertext Based on an Information Relevance Model
NASA Technical Reports Server (NTRS)
Mathe, Nathalie; Chen, James
1994-01-01
Rapid and effective to information in large electronic documentation systems can be facilitated if information relevant in an individual user's content can be automatically supplied to this user. However most of this knowledge on contextual relevance is not found within the contents of documents, it is rather established incrementally by users during information access. We propose a new model for interactively learning contextual relevance during information retrieval, and incrementally adapting retrieved information to individual user profiles. The model, called a relevance network, records the relevance of references based on user feedback for specific queries and user profiles. It also generalizes such knowledge to later derive relevant references for similar queries and profiles. The relevance network lets users filter information by context of relevance. Compared to other approaches, it does not require any prior knowledge nor training. More importantly, our approach to adaptivity is user-centered. It facilitates acceptance and understanding by users by giving them shared control over the adaptation without disturbing their primary task. Users easily control when to adapt and when to use the adapted system. Lastly, the model is independent of the particular application used to access information, and supports sharing of adaptations among users.
Modelling Drug Abuse Epidemics in the Presence of Limited Rehabilitation Capacity.
Mushanyu, J; Nyabadza, F; Muchatibaya, G; Stewart, A G R
2016-12-01
The abuse of drugs is now an epidemic globally whose control has been mainly through rehabilitation. The demand for drug abuse rehabilitation has not been matched with the available capacity resulting in limited placement of addicts into rehabilitation. In this paper, we model limited rehabilitation through the Hill function incorporated into a system of nonlinear ordinary differential equations. Not every member of the community is equally likely to embark on drug use, risk structure is included to help differentiate those more likely (high risk) to abuse drugs and those less likely (low risk) to abuse drugs. It is shown that the model has multiple equilibria, and using the centre manifold theory, the model exhibits the phenomenon of backward bifurcation whose implications to rehabilitation are discussed. Sensitivity analysis and numerical simulations are performed. The results show that saturation in rehabilitation will in the long run lead to the escalation of drug abuse. This means that limited access to rehabilitation has negative implications in the fight against drug abuse where rehabilitation is the main form of control. This suggests that increased access to rehabilitation is likely to lower the drug abuse epidemic.
NASA Astrophysics Data System (ADS)
Kershaw, Philip; Lawrence, Bryan; Lowe, Dominic; Norton, Peter; Pascoe, Stephen
2010-05-01
CEDA (Centre for Environmental Data Archival) based at STFC Rutherford Appleton Laboratory is host to the BADC (British Atmospheric Data Centre) and NEODC (NERC Earth Observation Data Centre) with data holdings of over half a Petabyte. In the coming months this figure is set to increase by over one Petabyte through the BADC's role as one of three data centres to host the CMIP5 (Coupled Model Intercomparison Project Phase 5) core archive of climate model data. Quite apart from the problem of managing the storage of such large volumes there is the challenge of collating the data together from the modelling centres around the world and enabling access to these data for the user community. An infrastructure to support this is being developed under the US Earth System Grid (ESG) and related projects bringing together participating organisations together in a federation. The ESG architecture defines Gateways, the web interfaces that enable users to access data and data serving applications organised into Data Nodes. The BADC has been working in collaboration with US Earth System Grid team and other partners to develop a security system to restrict access to data. This provides single sign-on via both OpenID and PKI based means and uses role based authorisation facilitated by SAML and OpenID based interfaces for attribute retrieval. This presentation will provide an overview of the access control architecture and look at how this has been implemented for CEDA. CEDA has developed an expertise in data access and information services over several years through a number of projects to develop and enhance these capabilities. Participation in CMIP5 comes at a time when a number of other software development activities are coming to fruition. New services are in the process of being deployed alongside services making up the system for ESG. The security system must apply access control across this heterogeneous environment of different data services and technologies. One strand of the development efforts within CEDA has been the NDG (NERC Datagrid) Security system. This system has been extended to interoperate with ESG, greatly assisted by the standards based approach adopted for the ESG security architecture. Drawing from experience from previous projects the decision was taken to refactor the NDG Security software into a component based architecture to enable a separation of concerns between access control and the functionality of a given application being protected. Such an approach is only possible through a generic interface. At CEDA, this has been realised in the Python programming language using the WSGI (Web Server Gateway Interface) specification. A parallel Java filter based implementation is also under development with our US partners for use with the THREDDS Data Server. Using such technologies applications and middleware can be assembled into custom configurations to meet different requirements. In the case of access control, NDG Security middleware can be layered over the top of existing applications without the need to modify them. A RESTful approach to the application of authorisation policy has been key in this approach. We explore the practical implementation of such a scheme alongside the application of the ESG security architecture to CEDA's OGC web services implementation COWS.
Mina, George S; Gobrial, George F; Modi, Kalgi; Dominic, Paari
2016-08-08
The aim of this meta-analysis was to study the relation between access site and bivalirudin use on outcomes in patients with acute coronary syndrome (ACS). Bivalirudin and radial access use are 2 strategies that are increasingly used to lower major bleeding in patients with ACS undergoing invasive approaches. The interaction between these 2 strategies and the benefit of using them in combination are unclear. This analysis included randomized controlled trials that compared bivalirudin to heparin with or without glycoprotein IIb/IIIa inhibitors in patients with ACS and reported outcomes stratified by arterial access site. Meta-analyses of outcome data were performed on the basis of access site and anticoagulation regimen. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from event rates using random-effects models. Eight trials with a total of 27,491 patients were included. Bivalirudin reduced major bleeding risk in patients with femoral access (OR: 0.51; 95% CI: 0.46 to 0.6; p < 0.001) but not in patients with radial access (OR: 0.75; 95% CI: 0.45 to 1.26; p = 0.28). Moreover, radial access reduced major bleeding risk in patients treated with heparin (OR: 0.57; 95% CI: 0.43 to 0.77; p < 0.001) but not in patients treated with bivalirudin (OR: 0.96; 95% CI: 0.65 to 1.41; p = 0.83). There were no differences in major adverse cardiovascular events or all-cause mortality between bivalirudin and heparin, regardless of access site. Bivalirudin reduces bleeding risk only with femoral access, and radial access reduces bleeding risk only with heparin anticoagulation. Therefore, there is no additional benefit to the combined use of bivalirudin and radial access strategies in patients with ACS. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Access control and confidentiality in radiology
NASA Astrophysics Data System (ADS)
Noumeir, Rita; Chafik, Adil
2005-04-01
A medical record contains a large amount of data about the patient such as height, weight and blood pressure. It also contains sensitive information such as fertility, abortion, psychiatric data, sexually transmitted diseases and diagnostic results. Access to this information must be carefully controlled. Information technology has greatly improved patient care. The recent extensive deployment of digital medical images made diagnostic images promptly available to healthcare decision makers, regardless of their geographic location. Medical images are digitally archived, transferred on telecommunication networks, and visualized on computer screens. However, with the widespread use of computing and communication technologies in healthcare, the issue of data security has become increasingly important. Most of the work until now has focused on the security of data communication to ensure its integrity, authentication, confidentiality and user accountability. The mechanisms that have been proposed to achieve the security of data communication are not specific to healthcare. Data integrity can be achieved with data signature. Data authentication can be achieved with certificate exchange. Data confidentiality can be achieved with encryption. User accountability can be achieved with audits. Although these mechanisms are essential to ensure data security during its transfer on the network, access control is needed in order to ensure data confidentiality and privacy within the information system application. In this paper, we present and discuss an access control mechanism that takes into account the notion of a care process. Radiology information is categorized and a model to enforce data privacy is proposed.
Enterprise systems security management: a framework for breakthrough protection
NASA Astrophysics Data System (ADS)
Farroha, Bassam S.; Farroha, Deborah L.
2010-04-01
Securing the DoD information network is a tremendous task due to its size, access locations and the amount of network intrusion attempts on a daily basis. This analysis investigates methods/architecture options to deliver capabilities for secure information sharing environment. Crypto-binding and intelligent access controls are basic requirements for secure information sharing in a net-centric environment. We introduce many of the new technology components to secure the enterprise. The cooperative mission requirements lead to developing automatic data discovery and data stewards granting access to Cross Domain (CD) data repositories or live streaming data. Multiple architecture models are investigated to determine best-of-breed approaches including SOA and Private/Public Clouds.
Kolb, Erik M; Kelly, Scott A; Garland, Theodore
2013-03-15
Exercise is known to be rewarding and have positive effects on mental and physical health. Excessive exercise, however, can be the result of an underlying behavioral/physiological addiction. Both humans who exercise regularly and rodent models of exercise addiction sometimes display behavioral withdrawal symptoms, including depression and anxiety, when exercise is denied. However, few studies have examined the physiological state that occurs during this withdrawal period. Alterations in blood pressure (BP) are common physiological indicators of withdrawal in a variety of addictions. In this study, we examined exercise withdrawal in four replicate lines of mice selectively bred for high voluntary wheel running (HR lines). Mice from the HR lines run almost 3-fold greater distances on wheels than those from non-selected control lines, and have altered brain activity as well as increased behavioral despair when wheel access is removed. We tested the hypothesis that male HR mice have an altered cardiovascular response (heart rate, systolic, diastolic, and mean arterial pressure [MAP]) during exercise withdrawal. Measurements using an occlusion tail-cuff system were taken during 8 days of baseline, 6 days of wheel access, and 2 days of withdrawal (wheel access blocked). During withdrawal, HR mice had significantly lower systolic BP, diastolic BP, and MAP than controls, potentially indicating a differential dependence on voluntary wheel running in HR mice. This is the first characterization of a cardiovascular withdrawal response in an animal model of high voluntary exercise. Copyright © 2013. Published by Elsevier Inc.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-01
... Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers and Products Containing Same... synchronous dynamic random access memory controllers and products containing same by reason of infringement of... semiconductor chips having synchronous dynamic random access memory controllers and products containing same...
NASA Technical Reports Server (NTRS)
Bachelder, Edward; Hess, Ronald; Godfroy-Cooper, Martine; Aponso, Bimal
2017-01-01
In this study, behavioral models are developed that closely reproduced pulsive control response of two pilots from the experimental pool using markedly different control techniques (styles) while conducting a tracking task. An intriguing find was that the pilots appeared to: 1) produce a continuous, internally-generated stick signal that they integrated in time; 2) integrate the actual stick position; and 3) compare the two integrations to issue and cease pulse commands. This suggests that the pilots utilized kinesthetic feedback in order to perceive and integrate stick position, supporting the hypothesis that pilots can access and employ the proprioceptive inner feedback loop proposed by Hess' pilot Structural Model. The Pulse Models used in conjunction with the pilot Structural Model closely recreated the pilot data both in the frequency and time domains during closed-loop simulation. This indicates that for the range of tasks and control styles encountered, the models captured the fundamental mechanisms governing pulsive and control processes. The pilot Pulse Models give important insight for the amount of remnant (stick output uncorrelated with the forcing function) that arises from nonlinear pilot technique, and for the remaining remnant arising from different sources unrelated to tracking control (i.e. neuromuscular tremor, reallocation of cognitive resources, etc.).
A federated capability-based access control mechanism for internet of things (IoTs)
NASA Astrophysics Data System (ADS)
Xu, Ronghua; Chen, Yu; Blasch, Erik; Chen, Genshe
2018-05-01
The prevalence of Internet of Things (IoTs) allows heterogeneous embedded smart devices to collaboratively provide intelligent services with or without human intervention. While leveraging the large-scale IoT-based applications like Smart Gird and Smart Cities, IoT also incurs more concerns on privacy and security. Among the top security challenges that IoTs face is that access authorization is critical in resource and information protection over IoTs. Traditional access control approaches, like Access Control Lists (ACL), Role-based Access Control (RBAC) and Attribute-based Access Control (ABAC), are not able to provide a scalable, manageable and efficient mechanisms to meet requirement of IoT systems. The extraordinary large number of nodes, heterogeneity as well as dynamicity, necessitate more fine-grained, lightweight mechanisms for IoT devices. In this paper, a federated capability-based access control (FedCAC) framework is proposed to enable an effective access control processes to devices, services and information in large scale IoT systems. The federated capability delegation mechanism, based on a propagation tree, is illustrated for access permission propagation. An identity-based capability token management strategy is presented, which involves registering, propagation and revocation of the access authorization. Through delegating centralized authorization decision-making policy to local domain delegator, the access authorization process is locally conducted on the service provider that integrates situational awareness (SAW) and customized contextual conditions. Implemented and tested on both resources-constrained devices, like smart sensors and Raspberry PI, and non-resource-constrained devices, like laptops and smart phones, our experimental results demonstrate the feasibility of the proposed FedCAC approach to offer a scalable, lightweight and fine-grained access control solution to IoT systems connected to a system network.
de Jong, Johannes W; Meijboom, Karin E; Vanderschuren, Louk J M J; Adan, Roger A H
2013-01-01
The worldwide obesity epidemic poses an enormous and growing threat to public health. However, the neurobehavioral mechanisms of overeating and obesity are incompletely understood. It has been proposed that addiction-like processes may underlie certain forms of obesity, in particular those associated with binge eating disorder. To investigate the role of addiction-like processes in obesity, we adapted a model of cocaine addiction-like behavior in rats responding for highly palatable food. Here, we tested whether rats responding for highly palatable chocolate Ensure would come to show three criteria of addiction-like behavior, i.e., high motivation, continued seeking despite signaled non-availability and persistence of seeking despite aversive consequences. We also investigated whether exposure to a binge model (a diet consisting of alternating periods of limited food access and access to highly palatable food), promotes the appearance of food addiction-like behavior. Our data show substantial individual differences in control over palatable food seeking and taking, but no distinct subgroup of animals showing addiction-like behavior could be identified. Instead, we observed a wide range extending from low to very high control over palatable food intake. Exposure to the binge model did not affect control over palatable food seeking and taking, however. Animals that showed low control over palatable food intake (i.e., scored high on the three criteria for addiction-like behavior) were less sensitive to devaluation of the food reward and more prone to food-induced reinstatement of extinguished responding, indicating that control over palatable food intake is associated with habitual food intake and vulnerability to relapse. In conclusion, we present an animal model to assess control over food seeking and taking. Since diminished control over food intake is a major factor in the development of obesity, understanding its behavioral and neural underpinnings may facilitate improved management of the obesity epidemic.
47 CFR 95.645 - Control accessibility.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 47 Telecommunication 5 2013-10-01 2013-10-01 false Control accessibility. 95.645 Section 95.645 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Technical Regulations Certification Requirements § 95.645 Control accessibility. (a) No control...
47 CFR 95.645 - Control accessibility.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 47 Telecommunication 5 2014-10-01 2014-10-01 false Control accessibility. 95.645 Section 95.645 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Technical Regulations Certification Requirements § 95.645 Control accessibility. (a) No control...
47 CFR 95.645 - Control accessibility.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 5 2010-10-01 2010-10-01 false Control accessibility. 95.645 Section 95.645 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Technical Regulations Certification Requirements § 95.645 Control accessibility. (a) No control...
47 CFR 95.645 - Control accessibility.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 5 2011-10-01 2011-10-01 false Control accessibility. 95.645 Section 95.645 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Technical Regulations Certification Requirements § 95.645 Control accessibility. (a) No control...
Barbarich-Marsteller, Nicole C; Fornal, Casimir A; Takase, Luiz F; Bocarsly, Miriam E; Arner, Candice; Walsh, B Timothy; Hoebel, Bartley G; Jacobs, Barry L
2013-01-01
Activity-based anorexia (ABA) is an animal model of anorexia nervosa that mimics core features of the clinical psychiatric disorder, including severe food restriction, weight loss, and hyperactivity. The ABA model is currently being used to study starvation-induced changes in the brain. Here, we examined hippocampal cell proliferation in animals with ABA (or the appropriate control conditions). Adolescent female Sprague-Dawley rats were assigned to 4 groups: control (24h/day food access), food-restricted (1h/day food access), exercise (24h/day food and wheel access), and ABA (1h/day food access, 24h/day wheel access). After 3 days of ABA, 5-bromo-2'-deoxyuridine (BrdU; 200mg/kg, i.p.) was injected and the rats were perfused 2h later. Brains were removed and subsequently processed for BrdU and Ki67 immunohistochemistry. The acute induction of ABA reduced cell proliferation in the dentate gyrus. This effect was significant in the hilus region of the dentate gyrus, but not in the subgranular zone, where adult neurogenesis occurs. Marked decreases in cell proliferation were also observed in the surrounding dorsal hippocampus and in the corpus callosum. These results indicate a primary effect on gliogenesis rather than neurogenesis following 3 days of ABA. For each brain region studied (except SGZ), there was a strong positive correlation between the level of cell proliferation and body weight/food intake. Future studies should examine whether these changes are maintained following long-term weight restoration and whether alterations in neurogenesis occur following longer exposures to ABA. Copyright © 2012 Elsevier B.V. All rights reserved.
Bozorgmehr, Kayvan; Schneider, Christine; Joos, Stefanie
2015-11-09
Research on inequities in access to health care among asylum-seekers has focused on disparities between asylum-seekers and resident populations, but little attention has been paid to potential inequities in access to care within the group of asylum-seekers. We aimed to analyse the principles of horizontal equity (i.e., equal access for equal need irrespective of socioeconomic status, SES) and vertical equity (higher allocation of resources to those with higher need) among asylum-seekers in Germany. We performed a secondary exploratory analysis on cross-sectional data obtained from a population-based questionnaire survey among all asylum-seekers (aged 18 or above) registered in three administrative districts in Germany during the three-month study period (N = 1017). Data were collected on health care access (health care utilisation of four types of services and unmet medical need), health care need (approximated by sex, age and self-rated health status), and SES (highest educational attainment and subjective social status, SSS). We calculated odds ratios and 95% confidence intervals (CI) in multiple logistic regression models to analyse associations between SES indicators and access to health care under control of need. We contacted 60.4% (614) of the total asylum-seekers population, of which 25.4% (N = 156) participated in the study. Educational attainment showed no significant effect on health care access in crude models, but was positively associated with utilisation of psychotherapists and hospital admissions in adjusted models. Higher SSS was positively associated with health care utilisation of all types of services. The odds of hospitals admissions for asylum-seekers in the medium and highest SSS category were 3.18 times [1.06, 9.59] and 1.6 times [0.49, 5.23] the odds of those in the lowest SSS category. After controlling for need variables none of the SES indicators were significantly associated with measures of access to care, but a positive association remained, indicating higher utilisation of health care among asylum-seekers with higher SES. Age, sex or general health status were the only significant predictors of health care utilisation in fully adjusted models. The adjusted odds of reporting unmet medical needs among asylum-seekers with "fair/bad/very bad" health status were 2.16 times [0.84, 5.59] the odds of those with "good/very good" health status. Our findings revealed that utilisation of health services among asylum-seekers is associated with higher need (vertical equity met). Horizontal equity was met with respect to educational attainment for most outcomes, but a social gradient in health care utilisation was observed across SSS. Further confirmatory research is needed, especially on potential inequities in unmet medical need and on measurements of SES among asylum-seekers.
NASA Astrophysics Data System (ADS)
Ishii, Ken; Imaizumi, Tomohito; Abe, Koki; Takao, Yoshimi; Tamura, Shuko
This paper details a network-controlled measurement system for use in fisheries engineering. The target strength (TS) of fish is important in order to convert acoustic integration values obtained during acoustic surveys into estimates of fish abundance. The target strength pattern is measured with the combination of the rotation system for the aspect of the sample and the echo data acquisition system using the underwater supersonic wave. The user interface of the network architecture is designed for collaborative use with researchers in other organizations. The flexible network architecture is based on the web direct-access model for the rotation mechanism. The user interface is available for monitoring and controlling via a web browser that is installed in any terminal PC (personal computer). Previously the combination of two applications was performed not by a web browser but by the exclusive interface program. So a connection model is proposed between two applications by indirect communication via the DCOM (Distributed Component Object Model) server and added in the web direct-access model. A prompt report system in the TS measurement system and a positioning and measurement system using an electric flatcar via a web browser are developed. By a secure network architecture, DCOM communications via both Intranet and LAN are successfully certificated.
Martin, Julien; Fackler, Paul L.; Nichols, James D.; Runge, Michael C.; McIntyre, Carol L.; Lubow, Bruce L.; McCluskie, Maggie C.; Schmutz, Joel A.
2011-01-01
Unintended effects of recreational activities in protected areas are of growing concern. We used an adaptive-management framework to develop guidelines for optimally managing hiking activities to maintain desired levels of territory occupancy and reproductive success of Golden Eagles (Aquila chrysaetos) in Denali National Park (Alaska, U.S.A.). The management decision was to restrict human access (hikers) to particular nesting territories to reduce disturbance. The management objective was to minimize restrictions on hikers while maintaining reproductive performance of eagles above some specified level. We based our decision analysis on predictive models of site occupancy of eagles developed using a combination of expert opinion and data collected from 93 eagle territories over 20 years. The best predictive model showed that restricting human access to eagle territories had little effect on occupancy dynamics. However, when considering important sources of uncertainty in the models, including environmental stochasticity, imperfect detection of hares on which eagles prey, and model uncertainty, restricting access of territories to hikers improved eagle reproduction substantially. An adaptive management framework such as ours may help reduce uncertainty of the effects of hiking activities on Golden Eagles
Logical Access Control Mechanisms in Computer Systems.
ERIC Educational Resources Information Center
Hsiao, David K.
The subject of access control mechanisms in computer systems is concerned with effective means to protect the anonymity of private information on the one hand, and to regulate the access to shareable information on the other hand. Effective means for access control may be considered on three levels: memory, process and logical. This report is a…
Market Impact of Foot-and-Mouth Disease Control Strategies: A UK Case Study
Feng, Siyi; Patton, Myles; Davis, John
2017-01-01
Foot-and-mouth disease (FMD) poses a serious threat to the agricultural sector due to its highly contagious nature. Outbreaks of FMD can lead to substantial disruptions to livestock markets due to loss of production and access to international markets. In a previously FMD-free country, the use of vaccination to augment control of an FMD outbreak is increasingly being recognized as an alternative control strategy to direct slaughtering [stamping-out (SO)]. The choice of control strategy has implications on production, trade, and hence prices of the sector. Specific choice of eradication strategies depends on their costs and benefits. Economic impact assessments are often based on benefit–cost framework, which provide detailed information on the changes in profit for a farm or budget implications for a government (1). However, this framework cannot capture price effects caused by changes in production due to culling of animals; access to international markets; and consumers’ reaction. These three impacts combine to affect equilibrium within commodity markets (2). This paper provides assessment of sectoral level impacts of the eradication choices of FMD outbreaks, which are typically not available from benefit–cost framework, in the context of the UK. The FAPRI-UK model, a partial equilibrium model of the agricultural sector, is utilized to investigate market outcomes of different control strategies (namely SO and vaccinate-to-die) in the case of FMD outbreaks. The outputs from the simulations of the EXODIS epidemiological model (number of animals culled/vaccinated and duration of outbreak) are used as inputs within the economic model to capture the overall price impact of the animal destruction, export ban, and consumers’ response. PMID:28920059
NASA Technical Reports Server (NTRS)
Schwab, Andrew J. (Inventor); Aylor, James (Inventor); Hitchcock, Charles Young (Inventor); Wulf, William A. (Inventor); McKee, Sally A. (Inventor); Moyer, Stephen A. (Inventor); Klenke, Robert (Inventor)
2000-01-01
A data processing system is disclosed which comprises a data processor and memory control device for controlling the access of information from the memory. The memory control device includes temporary storage and decision ability for determining what order to execute the memory accesses. The compiler detects the requirements of the data processor and selects the data to stream to the memory control device which determines a memory access order. The order in which to access said information is selected based on the location of information stored in the memory. The information is repeatedly accessed from memory and stored in the temporary storage until all streamed information is accessed. The information is stored until required by the data processor. The selection of the order in which to access information maximizes bandwidth and decreases the retrieval time.
A Model of Cooperation: The VALNet Project.
ERIC Educational Resources Information Center
Oberg, Larry R.
1986-01-01
Description of VALNet (Valley Library Consortium), a consortium of public, academic, and school libraries in Idaho, highlights proposed online public access union catalog which would include nonbibliographic and referral files and circulation and serials control modules. The political climate, marketing, needs assessment, support and consultation,…
An energy-efficient rate adaptive media access protocol (RA-MAC) for long-lived sensor networks.
Hu, Wen; Chen, Quanjun; Corke, Peter; O'Rourke, Damien
2010-01-01
We introduce an energy-efficient Rate Adaptive Media Access Control (RA-MAC) algorithm for long-lived Wireless Sensor Networks (WSNs). Previous research shows that the dynamic and lossy nature of wireless communications is one of the major challenges to reliable data delivery in WSNs. RA-MAC achieves high link reliability in such situations by dynamically trading off data rate for channel gain. The extra gain that can be achieved reduces the packet loss rate which contributes to reduced energy expenditure through a reduced numbers of retransmissions. We achieve this at the expense of raw bit rate which generally far exceeds the application's link requirement. To minimize communication energy consumption, RA-MAC selects the optimal data rate based on the estimated link quality at each data rate and an analytical model of the energy consumption. Our model shows how the selected data rate depends on different channel conditions in order to minimize energy consumption. We have implemented RA-MAC in TinyOS for an off-the-shelf sensor platform (the TinyNode) on top of a state-of-the-art WSN Media Access Control Protocol, SCP-MAC, and evaluated its performance by comparing our implementation with the original SCP-MAC using both simulation and experiment.
Complication with Intraosseous Access: Scandinavian Users’ Experience
Hallas, Peter; Brabrand, Mikkel; Folkestad, Lars
2013-01-01
Introduction: Intraosseous access (IO) is indicated if vascular access cannot be quickly established during resuscitation. Complication rates are estimated to be low, based on small patient series, model or cadaver studies, and case reports. However, user experience with IO use in real-life emergency situations might differ from the results in the controlled environment of model studies and small patient series. We performed a survey of IO use in real-life emergency situations to assess users’ experiences of complications. Methods: An online questionnaire was sent to Scandinavian emergency physicians, anesthesiologists and pediatricians. Results: 1,802 clinical cases of IO use was reported by n=386 responders. Commonly reported complications with establishing IO access were patient discomfort/pain (7.1%), difficulties with penetration of periosteum with IO needle (10.3%), difficulties with aspiration of bone marrow (12.3%), and bended/broken needle (4.0%). When using an established IO access the reported complications were difficulties with injection fluid and drugs after IO insertion (7.4%), slow infusion (despite use of pressure bag) (8.8%), displacement after insertion (8.5%), and extravasation (3.7%). Compartment syndrome and osteomyelitis occurred in 0.6% and 0.4% of cases respectively. Conclusion: In users’ recollection of real-life IO use, perceived complications were more frequent than usually reported from model studies. The perceived difficulties with using IO could affect the willingness of medical staff to use IO. Therefore, user experience should be addressed both in education of how to use, and research and development of IOs. PMID:24106537
Synthetic biology to access and expand nature’s chemical diversity
Smanski, Michael J.; Zhou, Hui; Claesen, Jan; Shen, Ben; Fischbach, Michael; Voigt, Christopher A.
2016-01-01
Bacterial genomes encode the biosynthetic potential to produce hundreds of thousands of complex molecules with diverse applications, from medicine to agriculture and materials. Economically accessing the potential encoded within sequenced genomes promises to reinvigorate waning drug discovery pipelines and provide novel routes to intricate chemicals. This is a tremendous undertaking, as the pathways often comprise dozens of genes spanning as much as 100+ kiliobases of DNA, are controlled by complex regulatory networks, and the most interesting molecules are made by non-model organisms. Advances in synthetic biology address these issues, including DNA construction technologies, genetic parts for precision expression control, synthetic regulatory circuits, computer aided design, and multiplexed genome engineering. Collectively, these technologies are moving towards an era when chemicals can be accessed en mass based on sequence information alone. This will enable the harnessing of metagenomic data and massive strain banks for high-throughput molecular discovery and, ultimately, the ability to forward design pathways to complex chemicals not found in nature. PMID:26876034
An SSH key management system: easing the pain of managing key/user/account associations
NASA Astrophysics Data System (ADS)
Arkhipkin, D.; Betts, W.; Lauret, J.; Shiryaev, A.
2008-07-01
Cyber security requirements for secure access to computing facilities often call for access controls via gatekeepers and the use of two-factor authentication. Using SSH keys to satisfy the two factor authentication requirement has introduced a potentially challenging task of managing the keys and their associations with individual users and user accounts. Approaches for a facility with the simple model of one remote user corresponding to one local user would not work at facilities that require a many-to-many mapping between users and accounts on multiple systems. We will present an SSH key management system we developed, tested and deployed to address the many-to-many dilemma in the environment of the STAR experiment. We will explain its use in an online computing context and explain how it makes possible the management and tracing of group account access spread over many sub-system components (data acquisition, slow controls, trigger, detector instrumentation, etc.) without the use of shared passwords for remote logins.
Fostering Team Awareness in Earth System Modeling Communities
NASA Astrophysics Data System (ADS)
Easterbrook, S. M.; Lawson, A.; Strong, S.
2009-12-01
Existing Global Climate Models are typically managed and controlled at a single site, with varied levels of participation by scientists outside the core lab. As these models evolve to encompass a wider set of earth systems, this central control of the modeling effort becomes a bottleneck. But such models cannot evolve to become fully distributed open source projects unless they address the imbalance in the availability of communication channels: scientists at the core site have access to regular face-to-face communication with one another, while those at remote sites have access to only a subset of these conversations - e.g. formally scheduled teleconferences and user meetings. Because of this imbalance, critical decision making can be hidden from many participants, their code contributions can interact in unanticipated ways, and the community loses awareness of who knows what. We have documented some of these problems in a field study at one climate modeling centre, and started to develop tools to overcome these problems. We report on one such tool, TracSNAP, which analyzes the social network of the scientists contributing code to the model by extracting the data in an existing project code repository. The tool presents the results of this analysis to modelers and model users in a number of ways: recommendation for who has expertise on particular code modules, suggestions for code sections that are related to files being worked on, and visualizations of team communication patterns. The tool is currently available as a plugin for the Trac bug tracking system.
Solon, Orville; Peabody, John W; Woo, Kimberly; Quimbo, Stella A; Florentino, Jhiedon; Shimkhada, Riti
2009-09-01
Even when health insurance coverage is available, health policies may not be effective at increasing coverage among vulnerable populations. New approaches are needed to improve access to care. We experimentally introduced a novel intervention that uses Policy Navigators to increase health insurance enrollment in a poor population. We used data from the Quality Improvement Demonstration Study (QIDS), a randomized experiment taking place at the district level in the Visayas region of the Philippines. In two arms of the study, we compared the effects of introducing Policy Navigators to controls. The Policy Navigators advocated for improved access to care by providing regular system-level expertise directly to the policy-makers, municipal mayors and governors responsible for paying for and enrolling poor households into the health insurance program. Using regression models, we compared levels of enrollment in our intervention versus control sites. We also assessed the cost-effectiveness of marginal increases in enrollment. We found that Policy Navigators improved enrollment in health insurance between 39% and 102% compared to the controls. Policy navigators were cost-effective at 0.86 USD per enrollee. However, supplementary national government campaigns, which were implemented to further increase coverage, attenuated normal enrollment efforts. Policy Navigators appear to be effective in improving access to care and their success underscores the importance of local-level strategies for improving enrollment.
Solon, Orville; Peabody, John W.; Woo, Kimberly; Quimbo, Stella A.; Florentino, Jhiedon; Shimkhada, Riti
2009-01-01
Objectives Even when health insurance coverage is available, health policies may not be effective at increasing coverage among vulnerable populations. New approaches are needed to improve access to care. We experimentally introduced a novel intervention that uses Policy Navigators to increase health insurance enrollment in a poor population. Methods We used data from the Quality Improvement Demonstration Study (QIDS), a randomized experiment taking place at the district level in the Visayas region of the Philippines. In two arms of the study, we compared the effects of introducing Policy Navigators to controls. The Policy Navigators advocated for improved access to care by providing regular system-level expertise directly to the policy-makers, municipal mayors and governors responsible for paying for and enrolling poor households into the health insurance program. Using regression models, we compared levels of enrollment in our intervention versus control sites. We also assessed the cost effectiveness of marginal increases in enrollment. Results We found that Policy Navigators improved enrollment in health insurance between 39 and 102% compared to the controls. Policy navigators were cost-effective at $0.86 USD per enrollee. However, supplementary national government campaigns, which were implemented to further increase coverage, attenuated normal enrollment efforts. Conclusion Policy Navigators appear to be effective in improving access to care and their success underscores the importance of local-level strategies for improving enrollment. PMID:19349090
Distributed clinical data sharing via dynamic access-control policy transformation.
Rezaeibagha, Fatemeh; Mu, Yi
2016-05-01
Data sharing in electronic health record (EHR) systems is important for improving the quality of healthcare delivery. Data sharing, however, has raised some security and privacy concerns because healthcare data could be potentially accessible by a variety of users, which could lead to privacy exposure of patients. Without addressing this issue, large-scale adoption and sharing of EHR data are impractical. The traditional solution to the problem is via encryption. Although encryption can be applied to access control, it is not applicable for complex EHR systems that require multiple domains (e.g. public and private clouds) with various access requirements. This study was carried out to address the security and privacy issues of EHR data sharing with our novel access-control mechanism, which captures the scenario of the hybrid clouds and need of access-control policy transformation, to provide secure and privacy-preserving data sharing among different healthcare enterprises. We introduce an access-control mechanism with some cryptographic building blocks and present a novel approach for secure EHR data sharing and access-control policy transformation in EHR systems for hybrid clouds. We propose a useful data sharing system for healthcare providers to handle various EHR users who have various access privileges in different cloud environments. A systematic study has been conducted on data sharing in EHR systems to provide a solution to the security and privacy issues. In conclusion, we introduce an access-control method for privacy protection of EHRs and EHR policy transformation that allows an EHR access-control policy to be transformed from a private cloud to a public cloud. This method has never been studied previously in the literature. Furthermore, we provide a protocol to demonstrate policy transformation as an application scenario. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Nativi, S.; Santoro, M.
2009-12-01
Currently, one of the major challenges for scientific community is the study of climate change effects on life on Earth. To achieve this, it is crucial to understand how climate change will impact on biodiversity and, in this context, several application scenarios require modeling the impact of climate change on distribution of individual species. In the context of GEOSS AIP-2 (Global Earth Observation System of Systems, Architecture Implementation Pilot- Phase 2), the Climate Change & Biodiversity thematic Working Group developed three significant user scenarios. A couple of them make use of a GEOSS-based framework to study the impact of climate change factors on regional species distribution. The presentation introduces and discusses this framework which provides an interoperability infrastructures to loosely couple standard services and components to discover and access climate and biodiversity data, and run forecast and processing models. The framework is comprised of the following main components and services: a)GEO Portal: through this component end user is able to search, find and access the needed services for the scenario execution; b)Graphical User Interface (GUI): this component provides user interaction functionalities. It controls the workflow manager to perform the required operations for the scenario implementation; c)Use Scenario controller: this component acts as a workflow controller implementing the scenario business process -i.e. a typical climate change & biodiversity projection scenario; d)Service Broker implementing Mediation Services: this component realizes a distributed catalogue which federates several discovery and access components (exposing them through a unique CSW standard interface). Federated components publish climate, environmental and biodiversity datasets; e)Ecological Niche Model Server: this component is able to run one or more Ecological Niche Models (ENM) on selected biodiversity and climate datasets; f)Data Access Transaction server: this component publishes the model outputs. The framework was successfully tested in two use scenarios of the GEOSS AIP-2 Climate Change and Biodiversity WG aiming to predict species distribution changes due to Climate Change factors, with the scientific patronage of the University of Colorado and the University of Alaska. The first scenario dealt with the Pikas specie regional distribution in the Great Basin area (North America). While, the second one concerned the modeling of the Arctic Food Chain species in the North Pole area -the relationships between different environmental parameters and Polar Bears distribution was analyzed. Results are published in the GEOSS AIP-2 web site: http://www.ogcnetwork.net/AIP2develop .
76 FR 59481 - Ninth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-26
... Control Systems (Update to DO-230B): Agenda October 20, 2011 Welcome/Introductions/Administrative Remarks... 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY...
76 FR 50811 - Eighth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-16
... Control Systems (Update to DO-230B): Agenda September 15, 2011 Welcome/Introductions/Administrative... Committee 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY...
Comparison of FDMA and CDMA for second generation land-mobile satellite communications
NASA Technical Reports Server (NTRS)
Yongacoglu, A.; Lyons, R. G.; Mazur, B. A.
1990-01-01
Code Division Multiple Access (CDMA) and Frequency Division Multiple Access (FDMA) (both analog and digital) systems capacities are compared on the basis of identical link availabilities and physical propagation models. Parameters are optimized for a bandwidth limited, multibeam environment. For CDMA, the benefits of voice activated carriers, antenna discrimination, polarization reuse, return link power control and multipath suppression are included in the analysis. For FDMA, the advantages of bandwidth efficient modulation/coding combinations, voice activated carriers, polarization reuse, beam placement, and frequency staggering were taken into account.
Access Control in Location-Based Services
NASA Astrophysics Data System (ADS)
Ardagna, Claudio A.; Cremonini, Marco; de Capitani di Vimercati, Sabrina; Samarati, Pierangela
Recent enhancements in location technologies reliability and precision are fostering the development of a new wave of applications that make use of the location information of users. Such applications introduces new aspects of access control which should be addressed. On the one side, precise location information may play an important role and can be used to develop Location-based Access Control (LBAC) systems that integrate traditional access control mechanisms with conditions based on the physical position of users. On the other side, location information of users can be considered sensitive and access control solutions should be developed to protect it against unauthorized accesses and disclosures. In this chapter, we address these two aspects related to the use and protection of location information, discussing existing solutions, open issues, and some research directions.
1994-05-18
1801 Control System Architecture: The Standard and Non -Standard Models (Invited Paper) - M. E. Thuot, L. R. Dalesio, LANL...extracted beam intensity and feedback on lbe in lbe AGS, lbe non -linear space charge force can blow up lbe strength of lbe sextupole field to control lb...cromsings at the two experimental areas BO and DO, and bling the mas rnge accessible for discovery, a menu bar. In the menu bar there are controls to inject
NASA Astrophysics Data System (ADS)
Zaharov, A. A.; Nissenbaum, O. V.; Ponomaryov, K. Y.; Nesgovorov, E. S.
2018-01-01
In this paper we study application of Internet of Thing concept and devices to secure automated process control systems. We review different approaches in IoT (Internet of Things) architecture and design and propose them for several applications in security of automated process control systems. We consider an Attribute-based encryption in context of access control mechanism implementation and promote a secret key distribution scheme between attribute authorities and end devices.
Brady, Megan L.; Allan, Andrea M.; Caldwell, Kevin K.
2013-01-01
Background It has been estimated that approximately 12% of women consume alcohol at some time during their pregnancy, and as many as 5% of children born in the United States are impacted by prenatal alcohol exposure (PAE). The range of physical, behavioral, emotional, and social dysfunctions that are associated with PAE are collectively termed fetal alcohol spectrum disorder (FASD). Methods Using a saccharin-sweetened ethanol solution, we developed a limited access model of PAE. C57BL/6J mice were provided access to a solution of either 10% (w/v) ethanol and 0.066% (w/v) saccharin or 0.066% (w/v) saccharin (control) for 4 h/d. After establishing consistent drinking, mice were mated and continued drinking during gestation. Following parturition, solutions were decreased to 0% in a stepwise fashion over a period of 6 days. Characterization of the model included measurements of maternal consumption patterns, blood ethanol levels, litter size, pup weight, maternal care, and the effects of PAE on fear-conditioned and spatial learning, and locomotor activity. Results Mothers had mean daily ethanol intake of 7.17 ± 0.17 g ethanol/kg body weight per day, with average blood ethanol concentrations of 68.5 ± 9.2 mg/dl after 2 hours of drinking and 88.3 ± 11.5 mg/dl after 4 hours of drinking. Food and water consumption, maternal weight gain, litter size, pup weight, pup retrieval times, and time on nest did not differ between the alcohol-exposed and control animals. Compared with control offspring, mice that were exposed to ethanol prenatally displayed no difference in spontaneous locomotor activity but demonstrated learning deficits in 3 hippocampal-dependent tasks: delay fear conditioning, trace fear conditioning, and the delay nonmatch to place radial-arm maze task. Conclusions These results indicate that this model appropriately mimics the human condition of PAE and will be a useful tool in studying the learning deficits seen in FASD. PMID:21933200
Model learning for robot control: a survey.
Nguyen-Tuong, Duy; Peters, Jan
2011-11-01
Models are among the most essential tools in robotics, such as kinematics and dynamics models of the robot's own body and controllable external objects. It is widely believed that intelligent mammals also rely on internal models in order to generate their actions. However, while classical robotics relies on manually generated models that are based on human insights into physics, future autonomous, cognitive robots need to be able to automatically generate models that are based on information which is extracted from the data streams accessible to the robot. In this paper, we survey the progress in model learning with a strong focus on robot control on a kinematic as well as dynamical level. Here, a model describes essential information about the behavior of the environment and the influence of an agent on this environment. In the context of model-based learning control, we view the model from three different perspectives. First, we need to study the different possible model learning architectures for robotics. Second, we discuss what kind of problems these architecture and the domain of robotics imply for the applicable learning methods. From this discussion, we deduce future directions of real-time learning algorithms. Third, we show where these scenarios have been used successfully in several case studies.
An object-based storage model for distributed remote sensing images
NASA Astrophysics Data System (ADS)
Yu, Zhanwu; Li, Zhongmin; Zheng, Sheng
2006-10-01
It is very difficult to design an integrated storage solution for distributed remote sensing images to offer high performance network storage services and secure data sharing across platforms using current network storage models such as direct attached storage, network attached storage and storage area network. Object-based storage, as new generation network storage technology emerged recently, separates the data path, the control path and the management path, which solves the bottleneck problem of metadata existed in traditional storage models, and has the characteristics of parallel data access, data sharing across platforms, intelligence of storage devices and security of data access. We use the object-based storage in the storage management of remote sensing images to construct an object-based storage model for distributed remote sensing images. In the storage model, remote sensing images are organized as remote sensing objects stored in the object-based storage devices. According to the storage model, we present the architecture of a distributed remote sensing images application system based on object-based storage, and give some test results about the write performance comparison of traditional network storage model and object-based storage model.
76 FR 38742 - Seventh Meeting: RTCA Special Committee 224: Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-01
... Control Systems (Update to DO-230B): Agenda July 15, 2011 Welcome/Introductions/Administrative Remarks... Committee 224: Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to...
Arrays of individually controlled ions suitable for two-dimensional quantum simulations
Mielenz, Manuel; Kalis, Henning; Wittemer, Matthias; ...
2016-06-13
A precisely controlled quantum system may reveal a fundamental understanding of another, less accessible system of interest. A universal quantum computer is currently out of reach, but an analogue quantum simulator that makes relevant observables, interactions and states of a quantum model accessible could permit insight into complex dynamics. Several platforms have been suggested and proof-of-principle experiments have been conducted. Here, we operate two-dimensional arrays of three trapped ions in individually controlled harmonic wells forming equilateral triangles with side lengths 40 and 80 μm. In our approach, which is scalable to arbitrary two-dimensional lattices, we demonstrate individual control of themore » electronic and motional degrees of freedom, preparation of a fiducial initial state with ion motion close to the ground state, as well as a tuning of couplings between ions within experimental sequences. Lastly, our work paves the way towards a quantum simulator of two-dimensional systems designed at will.« less
Extending MAM5 Meta-Model and JaCalIV E Framework to Integrate Smart Devices from Real Environments.
Rincon, J A; Poza-Lujan, Jose-Luis; Julian, V; Posadas-Yagüe, Juan-Luis; Carrascosa, C
2016-01-01
This paper presents the extension of a meta-model (MAM5) and a framework based on the model (JaCalIVE) for developing intelligent virtual environments. The goal of this extension is to develop augmented mirror worlds that represent a real and virtual world coupled, so that the virtual world not only reflects the real one, but also complements it. A new component called a smart resource artifact, that enables modelling and developing devices to access the real physical world, and a human in the loop agent to place a human in the system have been included in the meta-model and framework. The proposed extension of MAM5 has been tested by simulating a light control system where agents can access both virtual and real sensor/actuators through the smart resources developed. The results show that the use of real environment interactive elements (smart resource artifacts) in agent-based simulations allows to minimize the error between simulated and real system.
Extending MAM5 Meta-Model and JaCalIV E Framework to Integrate Smart Devices from Real Environments
2016-01-01
This paper presents the extension of a meta-model (MAM5) and a framework based on the model (JaCalIVE) for developing intelligent virtual environments. The goal of this extension is to develop augmented mirror worlds that represent a real and virtual world coupled, so that the virtual world not only reflects the real one, but also complements it. A new component called a smart resource artifact, that enables modelling and developing devices to access the real physical world, and a human in the loop agent to place a human in the system have been included in the meta-model and framework. The proposed extension of MAM5 has been tested by simulating a light control system where agents can access both virtual and real sensor/actuators through the smart resources developed. The results show that the use of real environment interactive elements (smart resource artifacts) in agent-based simulations allows to minimize the error between simulated and real system. PMID:26926691
Weed, Michael R; Wilcox, Kristin M; Ator, Nancy A; Hienz, Robert D
2008-06-01
Alcohol abuse is a major public health burden that can lead to many adverse health effects such as impaired hepatic, gastrointestinal, central nervous system and immune system function. Preclinical animal models of alcohol abuse allow for experimental control over variables often difficult to control in human clinical studies (e.g., ethanol exposure before or during the study, history of other drug use, access to medical care, nutritional status, etc). Nonhuman primate models in particular provide increased genetic, anatomic and physiologic similarity to humans, relative to rodent models. A small percentage of macaques will spontaneously consume large quantities of ethanol; however, most nonhuman primate models of "voluntary" ethanol intake produce relatively low daily ethanol intake in the majority of monkeys. To facilitate study of chronic exposure to high levels of ethanol intake, a macaque model has been developed that induces consistent, daily high-level ethanol consumption. This multiple-session procedure employed 4 drinking sessions per day, with sessions occurring once every 6 hours. The group average alcohol consumption was 4.6 g/kg/d (SEM 0.4), roughly twice the group average consumption of previous reports. Ethanol drinking sessions produced group mean blood ethanol levels of 95 mg/dl after 60 minutes, and fine motor control was impaired up to 90 minutes after a drinking session. This model of multiple-session, limited access, oral ethanol self-dosing produced consistent, high-level ethanol consumption with each session qualifying as a "binge" drinking session using the definition of "binge" provided by the NIAAA (>80 mg/dl/session). This model of ethanol drinking in macaques will be of great utility in the study of immunological, physiological and behavioral effects of ethanol in nonhuman primates.
Simulating the Historical Process To Create Laboratory Exercises That Teach Research Methods.
ERIC Educational Resources Information Center
Alcock, James
1994-01-01
Explains how controlling student access to data can be used as a strategy enabling students to take the role of a research geologist. Students develop models based on limited data and conduct field tests by comparing their predictions with the additional data. (DDR)
Safety of Mixed Model Access Control in a Multilevel System
2014-06-01
SOFTWARE ENGINEERING from the NAVAL POSTGRADUATE SCHOOL June 2014 Author: Randall J. Arvay Approved by: James Bret Michael Dan C . Boger...5 B. HYPOTHESIS..................................................................................................7 C . BACKGROUND...27 C . USE CASE ANALYSIS .................................................................................30 1. Use Case
Access Control of Web- and Java-Based Applications
NASA Technical Reports Server (NTRS)
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
A Flexible Component based Access Control Architecture for OPeNDAP Services
NASA Astrophysics Data System (ADS)
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. These components filter requests to the service they protect and apply the required authentication and authorisation schemes. Filters have been developed for OpenID and SSL client based authentication. The latter enabling access with MyProxy issued credentials. By preserving a clear separation between the security and application functionality, multiple authentication technologies may be supported without the need for modification to the underlying OPeNDAP application. The software has been developed in the Python programming language securing the Python based OPeNDAP implementation, PyDAP. This utilises the Python WSGI (Web Server Gateway Interface) specification to create distinct security filter components. Work is also currently underway to develop a parallel Java based filter implementation to secure the THREDDS Data Server. Whilst the ability to apply this flexible approach to the server side security layer is important, the development of compatible client software is vital to the take up of these services across a wide user base. To date PyDAP and wget based clients have been tested and work is planned to integrate the required security interface into the netCDF API. This forms part of ongoing collaboration with the OPeNDAP user and development community to ensure interoperability.
Learning Relational Policies from Electronic Health Record Access Logs
Malin, Bradley; Nyemba, Steve; Paulett, John
2011-01-01
Modern healthcare organizations (HCOs) are composed of complex dynamic teams to ensure clinical operations are executed in a quick and competent manner. At the same time, the fluid nature of such environments hinders administrators' efforts to define access control policies that appropriately balance patient privacy and healthcare functions. Manual efforts to define these policies are labor-intensive and error-prone, often resulting in systems that endow certain care providers with overly broad access to patients' medical records while restricting other providers from legitimate and timely use. In this work, we propose an alternative method to generate these policies by automatically mining usage patterns from electronic health record (EHR) systems. EHR systems are increasingly being integrated into clinical environments and our approach is designed to be generalizable across HCOs, thus assisting in the design and evaluation of local access control policies. Our technique, which is grounded in data mining and social network analysis theory, extracts a statistical model of the organization from the access logs of its EHRs. In doing so, our approach enables the review of predefined policies, as well as the discovery of unknown behaviors. We evaluate our approach with five months of access logs from the Vanderbilt University Medical Center and confirm the existence of stable social structures and intuitive business operations. Additionally, we demonstrate that there is significant turnover in the interactions between users in the HCO and that policies learned at the department level afford greater stability over time. PMID:21277996
Rodriguez-Calero, Miguel Angel; Fernandez-Fernandez, Ismael; Molero-Ballester, Luis Javier; Matamalas-Massanet, Catalina; Moreno-Mejias, Luis; de Pedro-Gomez, Joan Ernest; Blanco-Mavillard, Ian; Morales-Asencio, Jose Miguel
2018-02-08
Patients with difficult venous access experience undesirable effects during healthcare, such as delayed diagnosis and initiation of treatment, stress and pain related to the technique and reduced satisfaction. This study aims to identify risk factors with which to model the appearance of difficulty in achieving peripheral venous puncture in hospital treatment. Case-control study. We will include adult patients requiring peripheral venous cannulation in eight public hospitals, excluding those in emergency situations and women in childbirth or during puerperium. The nurse who performs the technique will record in an anonymised register variables related to the intervention. Subsequently, a researcher will extract the health variables from the patient's medical history. Patients who present one of the following conditions will be assigned to the case group: two or more failed punctures, need for puncture support, need for central access after failure to achieve peripheral access, or decision to reject the technique. The control group will be obtained from records of patients who do not meet the above conditions. It has been stated a minimum sample size of 2070 patients, 207 cases and 1863 controls.A descriptive analysis will be made of the distribution of the phenomenon. The variables hypothesised to be risk factors for the appearance of difficult venous cannulation will be studied using a logistic regression model. The study was funded in January 2017 and obtained ethical approval from the Research Ethics Committee of the Balearic Islands. Informed consent will be obtained prior to data collection. Results will be published in a peer-reviewed scientific journal. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Steil, Garry M; Hipszer, Brian; Reifman, Jaques
2010-05-01
One year after its initial meeting, the Glycemia Modeling Working Group reconvened during the 2009 Diabetes Technology Meeting in San Francisco, CA. The discussion, involving 39 scientists, again focused on the need for individual investigators to have access to the clinical data required to develop and refine models of glucose metabolism, the need to understand the differences among the distinct models and control algorithms, and the significance of day-to-day subject variability. The key conclusion was that model-based comparisons of different control algorithms, or the models themselves, are limited by the inability to access individual model-patient parameters. It was widely agreed that these parameters, as opposed to the average parameters that are typically reported, are necessary to perform such comparisons. However, the prevailing view was that, if investigators were to make the parameters available, it would limit their ability (and that of their institution) to benefit from the invested work in developing their models. A general agreement was reached regarding the importance of each model having an insulin pharmacokinetic/pharmacodynamic profile that is not different from profiles reported in the literature (88% of the respondents agreed that the model should have similar curves or be analyzed separately) and the importance of capturing intraday variance in insulin sensitivity (91% of the respondents indicated that this could result in changes in fasting glucose of >or=15%, with 52% of the respondents believing that the variability could effect changes of >or=30%). Seventy-six percent of the participants indicated that high-fat meals were thought to effect changes in other model parameters in addition to gastric emptying. There was also widespread consensus as to how a closed-loop controller should respond to day-to-day changes in model parameters (with 76% of the participants indicating that fasting glucose should be within 15% of target, with 30% of the participants believing that it should be at target). The group was evenly divided as to whether the glucose sensor per se continues to be the major obstacle in achieving closed-loop control. Finally, virtually all participants agreed that a future two-day workshop should be organized to compare, contrast, and understand the differences among the different models and control algorithms. (c) 2010 Diabetes Technology Society.
NASA Technical Reports Server (NTRS)
Butler, Ricky W.; Divito, Ben L.; Holloway, C. Michael
1994-01-01
In this paper the design and formal verification of the lower levels of the Reliable Computing Platform (RCP), a fault-tolerant computing system for digital flight control applications, are presented. The RCP uses NMR-style redundancy to mask faults and internal majority voting to flush the effects of transient faults. Two new layers of the RCP hierarchy are introduced: the Minimal Voting refinement (DA_minv) of the Distributed Asynchronous (DA) model and the Local Executive (LE) Model. Both the DA_minv model and the LE model are specified formally and have been verified using the Ehdm verification system. All specifications and proofs are available electronically via the Internet using anonymous FTP or World Wide Web (WWW) access.
Common Badging and Access Control System (CBACS)
NASA Technical Reports Server (NTRS)
Dischinger, Portia
2005-01-01
This slide presentation presents NASA's Common Badging and Access Control System. NASA began a Smart Card implementation in January 2004. Following site surveys, it was determined that NASA's badging and access control systems required upgrades to common infrastructure in order to provide flexibly, usability, and return on investment prior to a smart card implantation. Common Badging and Access Control System (CBACS) provides the common infrastructure from which FIPS-201 compliant processes, systems, and credentials can be developed and used.
Cloud-assisted mobile-access of health data with privacy and auditability.
Tong, Yue; Sun, Jinyuan; Chow, Sherman S M; Li, Pan
2014-03-01
Motivated by the privacy issues, curbing the adoption of electronic healthcare systems and the wild success of cloud service models, we propose to build privacy into mobile healthcare systems with the help of the private cloud. Our system offers salient features including efficient key management, privacy-preserving data storage, and retrieval, especially for retrieval at emergencies, and auditability for misusing health data. Specifically, we propose to integrate key management from pseudorandom number generator for unlinkability, a secure indexing method for privacy-preserving keyword search which hides both search and access patterns based on redundancy, and integrate the concept of attribute-based encryption with threshold signing for providing role-based access control with auditability to prevent potential misbehavior, in both normal and emergency cases.
The Effect of the Home Environment on Physical Activity and Dietary Intake in Preschool Children
Østbye, Truls; Malhotra, Rahul; Stroo, Marissa; Lovelady, Cheryl; Brouwer, Rebecca; Zucker, Nancy; Fuemmeler, Bernard
2013-01-01
Background The effects of the home environment on child health behaviors related to obesity are unclear. Purpose To examine the role of the home physical activity (PA) and food environment on corresponding outcomes in young children, and assess maternal education/work status as a moderator. Methods Overweight or obese mothers reported on the home PA and food environment (accessibility, role modeling and parental policies). Outcomes included child moderate-vigorous PA (MVPA) and sedentary time derived from accelerometer data and two dietary factors (“junk” and healthy food intake scores) based on factor analysis of mother-reported food intake. Linear regression models assessed the net effect (controlling for child demographics, study arm, supplemental timepoint, maternal education/work status, child body mass index and accelerometer wear-time (for PA outcomes)) of the home environment on the outcomes and moderation by maternal education/work status. Data was collected in North Carolina from 2007–2011. Results Parental policies supporting PA increased MVPA time, and limiting access to unhealthy foods increased the healthy food intake score. Role modeling of healthy eating behaviors increased the healthy food intake score among children of mothers with no college education. Among children of mothers with no college education and not working, limiting access to unhealthy foods and role modeling reduced “junk” food intake scores while parental policies supporting family meals increased “junk” food intake scores. Conclusions To promote MVPA, parental policies supporting child PA are warranted. Limited access to unhealthy foods and role modeling of healthy eating may improve the quality of the child’s food intake. PMID:23736357
The effect of the home environment on physical activity and dietary intake in preschool children.
Østbye, T; Malhotra, R; Stroo, M; Lovelady, C; Brouwer, R; Zucker, N; Fuemmeler, B
2013-10-01
The effects of the home environment on child health behaviors related to obesity are unclear. To examine the role of the home physical activity (PA) and food environment on corresponding outcomes in young children, and assess maternal education/work status as a moderator. Overweight or obese mothers reported on the home PA and food environment (accessibility, role modeling and parental policies). Outcomes included child moderate-vigorous PA (MVPA) and sedentary time derived from accelerometer data and two dietary factors ('junk' and healthy food intake scores) based on factor analysis of mother-reported food intake. Linear regression models assessed the net effect (controlling for child demographics, study arm, supplemental time point, maternal education/work status, child body mass index and accelerometer wear time (for PA outcomes)) of the home environment on the outcomes and moderation by maternal education/work status. Data were collected in North Carolina from 2007 to 2011. Parental policies supporting PA increased MVPA time, and limiting access to unhealthy foods increased the healthy food intake score. Role modeling of healthy eating behaviors increased the healthy food intake score among children of mothers with no college education. Among children of mothers with no college education and not working, limiting access to unhealthy foods and role modeling reduced 'junk' food intake scores whereas parental policies supporting family meals increased 'junk' food intake scores. To promote MVPA, parental policies supporting child PA are warranted. Limited access to unhealthy foods and role modeling of healthy eating may improve the quality of the child's food intake.
Patel, Priti R; Yi, Sarah H; Booth, Stephanie; Bren, Virginia; Downham, Gemma; Hess, Sally; Kelley, Karen; Lincoln, Mary; Morrissette, Kathy; Lindberg, Curt; Jernigan, John A; Kallen, Alexander J
2013-08-01
Bloodstream infections (BSIs) cause substantial morbidity in hemodialysis patients. In 2009, the US Centers for Disease Control and Prevention (CDC) sponsored a collaborative project to prevent BSIs in outpatient hemodialysis facilities. We sought to assess the impact of a set of interventions on BSI and access-related BSI rates in participating facilities using data reported to the CDC's National Healthcare Safety Network (NHSN). Quality improvement project. Patients in 17 outpatient hemodialysis facilities that volunteered to participate. Facilities reported monthly event and denominator data to NHSN, received guidance from the CDC, and implemented an evidence-based intervention package that included chlorhexidine use for catheter exit-site care, staff training and competency assessments focused on catheter care and aseptic technique, hand hygiene and vascular access care audits, and feedback of infection and adherence rates to staff. Crude and modeled BSI and access-related BSI rates. Up to 12 months of preintervention (January 2009 through December 2009) and 15 months of intervention period (January 2010 through March 2011) data from participating centers were analyzed. Segmented regression analysis was used to assess changes in BSI and access-related BSI rates during the preintervention and intervention periods. Most (65%) participating facilities were hospital based. Pooled mean BSI and access-related BSI rates were 1.09 and 0.73 events per 100 patient-months during the preintervention period and 0.89 and 0.42 events per 100 patient-months during the intervention period, respectively. Modeled rates decreased 32% (P = 0.01) for BSIs and 54% (P < 0.001) for access-related BSIs at the start of the intervention period. Participating facilities were not representative of all outpatient hemodialysis centers nationally. There was no control arm to this quality improvement project. Facilities participating in a collaborative successfully decreased their BSI and access-related BSI rates. The decreased rates appeared to be maintained in the intervention period. These findings suggest that improved implementation of recommended practices can reduce BSIs in hemodialysis centers. Published by Elsevier Inc. on behalf of the National Kidney Foundation, Inc.
The Ecological Model Web Concept: A Consultative Infrastructure for Decision Makers and Researchers
NASA Astrophysics Data System (ADS)
Geller, G.; Nativi, S.
2011-12-01
Rapid climate and socioeconomic changes may be outrunning society's ability to understand, predict, and respond to change effectively. Decision makers want better information about what these changes will be and how various resources will be affected, while researchers want better understanding of the components and processes of ecological systems, how they interact, and how they respond to change. Although there are many excellent models in ecology and related disciplines, there is only limited coordination among them, and accessible, openly shared models or model systems that can be consulted to gain insight on important ecological questions or assist with decision-making are rare. A "consultative infrastructure" that increased access to and sharing of models and model outputs would benefit decision makers, researchers, as well as modelers. Of course, envisioning such an ambitious system is much easier than building it, but several complementary approaches exist that could contribute. The one discussed here is called the Model Web. This is a concept for an open-ended system of interoperable computer models and databases based on making models and their outputs available as services ("model as a service"). Initially, it might consist of a core of several models from which it could grow gradually as new models or databases were added. However, a model web would not be a monolithic, rigidly planned and built system--instead, like the World Wide Web, it would grow largely organically, with limited central control, within a framework of broad goals and data exchange standards. One difference from the WWW is that a model web is much harder to create, and has more pitfalls, and thus is a long term vision. However, technology, science, observations, and models have advanced enough so that parts of an ecological model web can be built and utilized now, forming a framework for gradual growth as well as a broadly accessible infrastructure. Ultimately, the value of a model web lies in the increase in access to and sharing of both models and model outputs. By lowering access barriers to models and their outputs there is less reinvention, more efficient use of resources, greater interaction among researchers and across disciplines, as well as other benefits. The growth of such a system of models fits well with the concept and architecture of the Global Earth Observing System of Systems (GEOSS) as well as the Semantic Web. And, while framed here in the context of ecological forecasting, the same concept can be applied to any discipline utilizing models.
Semantically Enriched Data Access Policies in eHealth.
Drozdowicz, Michał; Ganzha, Maria; Paprzycki, Marcin
2016-11-01
Internet of Things (IoT) requires novel solutions to facilitate autonomous, though controlled, resource access. Access policies have to facilitate interactions between heterogeneous entities (devices and humans). Here, we focus our attention on access control in eHealth. We propose an approach based on enriching policies, based on well-known and widely-used eXtensible Access Control Markup Language, with semantics. In the paper we describe an implementation of a Policy Information Point integrated with the HL7 Security and Privacy Ontology.
10 CFR 20.1601 - Control of access to high radiation areas.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 1 2010-01-01 2010-01-01 false Control of access to high radiation areas. 20.1601 Section 20.1601 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1601 Control of access to high radiation areas. (a...
77 FR 2343 - Eleventh Meeting: RTCA Special Committee 224, Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-17
... Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S... Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the eleventh meeting of RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held...
10 CFR 20.1601 - Control of access to high radiation areas.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 1 2014-01-01 2014-01-01 false Control of access to high radiation areas. 20.1601 Section 20.1601 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1601 Control of access to high radiation areas. (a...
10 CFR 20.1601 - Control of access to high radiation areas.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 1 2013-01-01 2013-01-01 false Control of access to high radiation areas. 20.1601 Section 20.1601 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1601 Control of access to high radiation areas. (a...
10 CFR 20.1601 - Control of access to high radiation areas.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 1 2011-01-01 2011-01-01 false Control of access to high radiation areas. 20.1601 Section 20.1601 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1601 Control of access to high radiation areas. (a...
10 CFR 20.1601 - Control of access to high radiation areas.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 1 2012-01-01 2012-01-01 false Control of access to high radiation areas. 20.1601 Section 20.1601 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1601 Control of access to high radiation areas. (a...
Evaluation of modified work zone traffic control devices at business accesses
DOT National Transportation Integrated Search
2001-01-01
Modified work zone traffic control devices at business accesses were evaluated on two Oregon Department of Transportation (ODOT) projects in 1999 and 2000. On one section project, blue Temporary Business Access" signs were used at business accesses d...
A simple method for long-term biliary access in large animals.
Andrews, J C; Knutsen, C; Smith, P; Prieskorn, D; Crudip, J; Klevering, J; Ensminger, W D
1988-07-01
A simple method to obtain long-term access to the biliary tree in dogs and pigs is presented. In ten dogs and four pigs, a cholecystectomy was performed, the cystic duct isolated, and a catheter inserted into the cut end of the cystic duct. The catheter was connected to a subcutaneous infusion port, producing a closed, internal system to allow long-term access. The catheter placement was successful in three of the pigs and all of the dogs. Thirty-five cholangiograms were obtained in the 13 subjects by accessing the port with a 20 gauge Huber needle and injecting small amounts (4-10 mL) of contrast under fluoroscopic control. Cholangiograms were obtained up to four months after catheter placement without evidence for catheter failure or surgically induced changes in the biliary tree. This model provides a simple, reliable means to obtain serial cholangiograms in a research setting.
Jaïdi, Faouzi; Labbene-Ayachi, Faten; Bouhoula, Adel
2016-12-01
Nowadays, e-healthcare is a main advancement and upcoming technology in healthcare industry that contributes to setting up automated and efficient healthcare infrastructures. Unfortunately, several security aspects remain as main challenges towards secure and privacy-preserving e-healthcare systems. From the access control perspective, e-healthcare systems face several issues due to the necessity of defining (at the same time) rigorous and flexible access control solutions. This delicate and irregular balance between flexibility and robustness has an immediate impact on the compliance of the deployed access control policy. To address this issue, the paper defines a general framework to organize thinking about verifying, validating and monitoring the compliance of access control policies in the context of e-healthcare databases. We study the problem of the conformity of low level policies within relational databases and we particularly focus on the case of a medical-records management database defined in the context of a Medical Information System. We propose an advanced solution for deploying reliable and efficient access control policies. Our solution extends the traditional lifecycle of an access control policy and allows mainly managing the compliance of the policy. We refer to an example to illustrate the relevance of our proposal.
Medical instrument data exchange.
Gumudavelli, Suman; McKneely, Paul K; Thongpithoonrat, Pongnarin; Gurkan, D; Chapman, Frank M
2008-01-01
Advances in medical devices and health care has been phenomenal during the recent years. Although medical device manufacturers have been improving their instruments, network connection of these instruments still rely on proprietary technologies. Even if the interface has been provided by the manufacturer (e.g., RS-232, USB, or Ethernet coupled with a proprietary API), there is no widely-accepted uniform data model to access data of various bedside instruments. There is a need for a common standard which allows for internetworking with the medical devices from different manufacturers. ISO/IEEE 11073 (X73) is a standard attempting to unify the interfaces of all medical devices. X73 defines a client access mechanism that would be implemented into the communication controllers (residing between an instrument and the network) in order to access/network patient data. On the other hand, MediCAN technology suite has been demonstrated with various medical instruments to achieve interfacing and networking with a similar goal in its open standardization approach. However, it provides a more generic definition for medical data to achieve flexibility for networking and client access mechanisms. In this paper, a comparison between the data model of X73 and MediCAN will be presented to encourage interoperability demonstrations of medical instruments.
Brennan, Meghan B; Allen, Glenn O; Ferguson, Patrick D; McBride, Joseph A; Crnich, Christopher J; Smith, Maureen A
2017-01-01
Avoiding major (above-ankle) amputation in patients with diabetic foot ulcers is best accomplished by multidisciplinary care teams with access to infectious disease specialists. However, access to infectious disease physicians is partially influenced by geography. We assessed the effect of living in a hospital referral region with a high geographic density of infectious disease physicians on major amputation for patients with diabetic foot ulcers. We studied geographic density, rather than infectious disease consultation, to capture both the direct and indirect (eg, informal consultation) effects of access to these providers on major amputation. We used a national retrospective cohort of 56440 Medicare enrollees with incident diabetic foot ulcers. Cox proportional hazard models were used to assess the relationship between infectious disease physician density and major amputation, while controlling for patient demographics, comorbidities, and ulcer severity. Living in hospital referral regions with high geographic density of infectious disease physicians was associated with a reduced risk of major amputation after controlling for demographics, comorbidities, and ulcer severity (hazard ratio, .83; 95% confidence interval, .75-.91; P < .001). The relationship between the geographic density of infectious disease physicians and major amputation was not different based on ulcer severity and was maintained when adjusting for socioeconomic factors and modeling amputation-free survival. Infectious disease physicians may play an important role in limb salvage. Future studies should explore whether improved access to infectious disease physicians results in fewer major amputations. © The Author 2017. Published by Oxford University Press on behalf of Infectious Diseases Society of America.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steele, B.J.
1996-12-31
There are many technologies emerging from this decade that can be used to help the law enforcement community protect the public as well as public and private facilities against ever increasing threats to this country and its resources. These technologies include sensors, closed circuit television (CCTV), access control, contraband detection, communications, control and display, barriers, and various component and system modeling techniques. This paper will introduce some of the various technologies that have been examined for the Department of Energy that could be applied to various law enforcement applications. They include: (1) scannerless laser radar; (2) next generation security systems;more » (3) response force video information helmet system; (4) access delay technologies; (5) rapidly deployable intrusion detection systems; and (6) cost risk benefit analysis.« less
BioModels.net Web Services, a free and integrated toolkit for computational modelling software.
Li, Chen; Courtot, Mélanie; Le Novère, Nicolas; Laibe, Camille
2010-05-01
Exchanging and sharing scientific results are essential for researchers in the field of computational modelling. BioModels.net defines agreed-upon standards for model curation. A fundamental one, MIRIAM (Minimum Information Requested in the Annotation of Models), standardises the annotation and curation process of quantitative models in biology. To support this standard, MIRIAM Resources maintains a set of standard data types for annotating models, and provides services for manipulating these annotations. Furthermore, BioModels.net creates controlled vocabularies, such as SBO (Systems Biology Ontology) which strictly indexes, defines and links terms used in Systems Biology. Finally, BioModels Database provides a free, centralised, publicly accessible database for storing, searching and retrieving curated and annotated computational models. Each resource provides a web interface to submit, search, retrieve and display its data. In addition, the BioModels.net team provides a set of Web Services which allows the community to programmatically access the resources. A user is then able to perform remote queries, such as retrieving a model and resolving all its MIRIAM Annotations, as well as getting the details about the associated SBO terms. These web services use established standards. Communications rely on SOAP (Simple Object Access Protocol) messages and the available queries are described in a WSDL (Web Services Description Language) file. Several libraries are provided in order to simplify the development of client software. BioModels.net Web Services make one step further for the researchers to simulate and understand the entirety of a biological system, by allowing them to retrieve biological models in their own tool, combine queries in workflows and efficiently analyse models.
Liu, Baolin; Jin, Zhixing; Qing, Zhao; Wang, Zhongning
2011-02-04
In the current work, we aimed to study the processing of phonological, orthographical, and lexical information of Chinese characters in sentence contexts, as well as to provide further evidence for psychological models. In the experiment, we designed sentences with expected, homophonic, orthographically similar, synonymous, and control characters as endings, respectively. The results indicated that P200 might be related to the early extraction of phonological information. Moreover, it might also represent immediate semantic and orthographic lexical access. This suggested that there might be a dual-route in cognitive processing, where the direct access route and the phonologically mediated access route both exist and interact with each other. The increased N400 under the control condition suggested that both phonological and orthographical information would influence semantic integration in Chinese sentence comprehension. The two positive peaks of the late positive shift might represent the semantic monitoring, and orthographical retrieval and reanalysis processing, respectively. Under the orthographically similar condition, orthographical retrieval and reanalysis processing was more difficult in comparison with the other conditions, which suggested that there might be direct access from orthography to semantic representation in cognitive processing. In conclusion, it was shown that the direct access hypothesis or the dual-route hypothesis could better explain cognitive processing in the brain. Copyright © 2010 Elsevier B.V. All rights reserved.
Assessing Strategies Against Gambiense Sleeping Sickness Through Mathematical Modeling
Rock, Kat S; Ndeffo-Mbah, Martial L; Castaño, Soledad; Palmer, Cody; Pandey, Abhishek; Atkins, Katherine E; Ndung’u, Joseph M; Hollingsworth, T Déirdre; Galvani, Alison; Bever, Caitlin; Chitnis, Nakul; Keeling, Matt J
2018-01-01
Abstract Background Control of gambiense sleeping sickness relies predominantly on passive and active screening of people, followed by treatment. Methods Mathematical modeling explores the potential of 3 complementary interventions in high- and low-transmission settings. Results Intervention strategies that included vector control are predicted to halt transmission most quickly. Targeted active screening, with better and more focused coverage, and enhanced passive surveillance, with improved access to diagnosis and treatment, are both estimated to avert many new infections but, when used alone, are unlikely to halt transmission before 2030 in high-risk settings. Conclusions There was general model consensus in the ranking of the 3 complementary interventions studied, although with discrepancies between the quantitative predictions due to differing epidemiological assumptions within the models. While these predictions provide generic insights into improving control, the most effective strategy in any situation depends on the specific epidemiology in the region and the associated costs. PMID:29860287
Neural network applications in telecommunications
NASA Technical Reports Server (NTRS)
Alspector, Joshua
1994-01-01
Neural network capabilities include automatic and organized handling of complex information, quick adaptation to continuously changing environments, nonlinear modeling, and parallel implementation. This viewgraph presentation presents Bellcore work on applications, learning chip computational function, learning system block diagram, neural network equalization, broadband access control, calling-card fraud detection, software reliability prediction, and conclusions.
A Prudent Access Control Behavioral Intention Model for the Healthcare Domain
ERIC Educational Resources Information Center
Mussa, Constance C.
2011-01-01
In recent years, many health care organizations have begun to take advantage of computerized information systems to facilitate more effective and efficient management and processing of information. However, commensurate with the vastly innovative enhancements that computer technology has contributed to traditional paper-based health care…
A School-Based Program for Overweight and Obese Adolescents: A Randomized Controlled Trial
ERIC Educational Resources Information Center
Pbert, Lori; Druker, Susan; Barton, Bruce; Schneider, Kristin L.; Olendzki, Barbara; Gapinski, Mary A.; Kurtz, Stephen; Osganian, Stavroula
2016-01-01
Background: Given the dramatic increase in adolescent overweight and obesity, models are needed for implementing weight management treatment through readily accessible venues. We evaluated the acceptability and efficacy of a school-based intervention consisting of school nurse-delivered counseling and an afterschool exercise program in improving…
Change Detection, Multiple Controllers, and Dynamic Environments: Insights from the Brain
ERIC Educational Resources Information Center
Pearson, John M.; Platt, Michael L.
2013-01-01
Foundational studies in decision making focused on behavior as the most accessible and reliable data on which to build theories of choice. More recent work, however, has incorporated neural data to provide insights unavailable from behavior alone. Among other contributions, these studies have validated reinforcement learning models by…
Xu, Lei; Fang, Wei-Yi; Zhu, Fu; Zhang, Hong-Guang; Liu, Kai
2017-05-25
Hypertension is a major risk factor for cardiovascular disease, and its control rate has remained low worldwide. Studies have found that telemonitoring blood pressure (BP) helped control hypertension in randomized controlled trials. However, little is known about its effect in a structured primary care model in which primary care physicians (PCPs) are partnering with cardiology specialists in electronic healthcare data sharing and medical interventions. This study aims to identify the effects of a coordinated PCP-cardiologist model that applies telemedicine tools to facilitate community hypertension control in China. Patients with hypertension receiving care at four community healthcare centers that are academically affiliated to Shanghai Chest Hospital, Shanghai JiaoTong University are eligible if they have had uncontrolled BP in the previous 3 months and access to mobile Internet. Study subjects are randomly assigned to three interventional groups: (1) usual care; (2) home-based BP telemonitor with embedded Global System for Mobile Communications (GSM) module and unlimited data plan, an app to access personal healthcare record and receive personalized lifestyle coaching contents, and proficiency training of their use; or (3) this plus coordinated PCP-cardiologist care in which PCPs and cardiologists share data via a secure CareLinker website to determine interventional approaches. The primary outcome is mean change in systolic blood pressure over a 12-month period. Secondary outcomes are changes of diastolic blood pressure, HbA1C, blood lipids, and medication adherence measured by the eight-item Morisky Medication Adherence Scale. This study will determine whether a coordinated PCP-Cardiologist Telemedicine Model that incorporates the latest telemedicine technologies will improve hypertension care. Success of the model would help streamline the present community healthcare processes and impact a greater number of patients with uncontrolled hypertension. ClinicalTrials.gov, NCT02919033 . Registered on 23 September 2016.
Anantha, Ram Venkatesh; Parry, Neil; Vogt, Kelly; Jain, Vipan; Crawford, Silvie; Leslie, Ken
2014-01-01
Background Acute care surgical services provide comprehensive emergency general surgical care while potentially using health care resources more efficiently. We assessed the volume and distribution of emergency general surgery (EGS) procedures before and after the implementation of the Acute Care and Emergency Surgery Service (ACCESS) at a Canadian tertiary care hospital and its effect on surgeon billings. Methods This single-centre retrospective case–control study compared adult patients who underwent EGS procedures between July and December 2009 (pre-ACCESS), to those who had surgery between July and December 2010 (post-ACCESS). Case distribution was compared between day (7 am to 3 pm), evening (3 pm to 11 pm) and night (11 pm to 7 am). Frequencies were compared using the χ2 test. Results Pre-ACCESS, 366 EGS procedures were performed: 24% during the day, 55% in the evening and 21% at night. Post-ACCESS, 463 operations were performed: 55% during the day, 36% in the evening and 9% at night. Reductions in night-time and evening EGS were 57% and 36% respectively (p < 0.001). Total surgeon billings for operations pre- and post-ACCESS were $281 066 and $287 075, respectively: remuneration was $6008 higher post-ACCESS for an additional 97 cases (p = 0.003). Using cost-modelling analysis, post-ACCESS surgeon billing for appendectomies, segmental colectomies, laparotomies and cholecystectomies all declined by $67 190, $125 215, $66 362, and $84 913, respectively (p < 0.001). Conclusion Acute care surgical services have dramatically shifted EGS from nighttime to daytime. Cost-modelling analysis demonstrates that these services have cost-savings potential for the health care system without reducing overall surgeon billing. PMID:24666462
Anantha, Ram Venkatesh; Parry, Neil; Vogt, Kelly; Jain, Vipan; Crawford, Silvie; Leslie, Ken
2014-04-01
Acute care surgical services provide comprehensive emergency general surgical care while potentially using health care resources more efficiently. We assessed the volume and distribution of emergency general surgery (EGS) procedures before and after the implementation of the Acute Care and Emergency Surgery Service (ACCESS) at a Canadian tertiary care hospital and its effect on surgeon billings. This single-centre retrospective case-control study compared adult patients who underwent EGS procedures between July and December 2009 (pre-ACCESS), to those who had surgery between July and December 2010 (post-ACCESS). Case distribution was compared between day (7 am to 3 pm), evening (3 pm to 11 pm) and night (11 pm to 7 am). Frequencies were compared using the χ(2) test. Pre-ACCESS, 366 EGS procedures were performed: 24% during the day, 55% in the evening and 21% at night. Post-ACCESS, 463 operations were performed: 55% during the day, 36% in the evening and 9% at night. Reductions in night-time and evening EGS were 57% and 36% respectively (p < 0.001). Total surgeon billings for operations pre- and post-ACCESS were $281 066 and $287 075, respectively: remuneration was $6008 higher post-ACCESS for an additional 97 cases (p = 0.003). Using cost-modelling analysis, post-ACCESS surgeon billing for appendectomies, segmental colectomies, laparotomies and cholecystectomies all declined by $67 190, $125 215, $66 362, and $84 913, respectively (p < 0.001). Acute care surgical services have dramatically shifted EGS from nighttime to daytime. Cost-modelling analysis demonstrates that these services have cost-savings potential for the health care system without reducing overall surgeon billing.
Integrated risk/cost planning models for the US Air Traffic system
NASA Technical Reports Server (NTRS)
Mulvey, J. M.; Zenios, S. A.
1985-01-01
A prototype network planning model for the U.S. Air Traffic control system is described. The model encompasses the dual objectives of managing collision risks and transportation costs where traffic flows can be related to these objectives. The underlying structure is a network graph with nonseparable convex costs; the model is solved efficiently by capitalizing on its intrinsic characteristics. Two specialized algorithms for solving the resulting problems are described: (1) truncated Newton, and (2) simplicial decomposition. The feasibility of the approach is demonstrated using data collected from a control center in the Midwest. Computational results with different computer systems are presented, including a vector supercomputer (CRAY-XMP). The risk/cost model has two primary uses: (1) as a strategic planning tool using aggregate flight information, and (2) as an integrated operational system for forecasting congestion and monitoring (controlling) flow throughout the U.S. In the latter case, access to a supercomputer is required due to the model's enormous size.
NASA Astrophysics Data System (ADS)
Tsaur, Woei-Jiunn; Pai, Haw-Tyng
2008-11-01
The applications of group computing and communication motivate the requirement to provide group access control in mobile ad hoc networks (MANETs). The operation in MANETs' groups performs a decentralized manner and accommodated membership dynamically. Moreover, due to lack of centralized control, MANETs' groups are inherently insecure and vulnerable to attacks from both within and outside the groups. Such features make access control more challenging in MANETs. Recently, several researchers have proposed group access control mechanisms in MANETs based on a variety of threshold signatures. However, these mechanisms cannot actually satisfy MANETs' dynamic environments. This is because the threshold-based mechanisms cannot be achieved when the number of members is not up to the threshold value. Hence, by combining the efficient elliptic curve cryptosystem, self-certified public key cryptosystem and secure filter technique, we construct dynamic key management schemes based on hierarchical clustering for securing group access control in MANETs. Specifically, the proposed schemes can constantly accomplish secure group access control only by renewing the secure filters of few cluster heads, when a cluster head joins or leaves a cross-cluster. In such a new way, we can find that the proposed group access control scheme can be very effective for securing practical applications in MANETs.
Simonyan, Vahan; Chumakov, Konstantin; Dingerdissen, Hayley; Faison, William; Goldweber, Scott; Golikov, Anton; Gulzar, Naila; Karagiannis, Konstantinos; Vinh Nguyen Lam, Phuc; Maudru, Thomas; Muravitskaja, Olesja; Osipova, Ekaterina; Pan, Yang; Pschenichnov, Alexey; Rostovtsev, Alexandre; Santana-Quintero, Luis; Smith, Krista; Thompson, Elaine E.; Tkachenko, Valery; Torcivia-Rodriguez, John; Wan, Quan; Wang, Jing; Wu, Tsung-Jung; Wilson, Carolyn; Mazumder, Raja
2016-01-01
The High-performance Integrated Virtual Environment (HIVE) is a distributed storage and compute environment designed primarily to handle next-generation sequencing (NGS) data. This multicomponent cloud infrastructure provides secure web access for authorized users to deposit, retrieve, annotate and compute on NGS data, and to analyse the outcomes using web interface visual environments appropriately built in collaboration with research and regulatory scientists and other end users. Unlike many massively parallel computing environments, HIVE uses a cloud control server which virtualizes services, not processes. It is both very robust and flexible due to the abstraction layer introduced between computational requests and operating system processes. The novel paradigm of moving computations to the data, instead of moving data to computational nodes, has proven to be significantly less taxing for both hardware and network infrastructure. The honeycomb data model developed for HIVE integrates metadata into an object-oriented model. Its distinction from other object-oriented databases is in the additional implementation of a unified application program interface to search, view and manipulate data of all types. This model simplifies the introduction of new data types, thereby minimizing the need for database restructuring and streamlining the development of new integrated information systems. The honeycomb model employs a highly secure hierarchical access control and permission system, allowing determination of data access privileges in a finely granular manner without flooding the security subsystem with a multiplicity of rules. HIVE infrastructure will allow engineers and scientists to perform NGS analysis in a manner that is both efficient and secure. HIVE is actively supported in public and private domains, and project collaborations are welcomed. Database URL: https://hive.biochemistry.gwu.edu PMID:26989153
Simonyan, Vahan; Chumakov, Konstantin; Dingerdissen, Hayley; Faison, William; Goldweber, Scott; Golikov, Anton; Gulzar, Naila; Karagiannis, Konstantinos; Vinh Nguyen Lam, Phuc; Maudru, Thomas; Muravitskaja, Olesja; Osipova, Ekaterina; Pan, Yang; Pschenichnov, Alexey; Rostovtsev, Alexandre; Santana-Quintero, Luis; Smith, Krista; Thompson, Elaine E; Tkachenko, Valery; Torcivia-Rodriguez, John; Voskanian, Alin; Wan, Quan; Wang, Jing; Wu, Tsung-Jung; Wilson, Carolyn; Mazumder, Raja
2016-01-01
The High-performance Integrated Virtual Environment (HIVE) is a distributed storage and compute environment designed primarily to handle next-generation sequencing (NGS) data. This multicomponent cloud infrastructure provides secure web access for authorized users to deposit, retrieve, annotate and compute on NGS data, and to analyse the outcomes using web interface visual environments appropriately built in collaboration with research and regulatory scientists and other end users. Unlike many massively parallel computing environments, HIVE uses a cloud control server which virtualizes services, not processes. It is both very robust and flexible due to the abstraction layer introduced between computational requests and operating system processes. The novel paradigm of moving computations to the data, instead of moving data to computational nodes, has proven to be significantly less taxing for both hardware and network infrastructure.The honeycomb data model developed for HIVE integrates metadata into an object-oriented model. Its distinction from other object-oriented databases is in the additional implementation of a unified application program interface to search, view and manipulate data of all types. This model simplifies the introduction of new data types, thereby minimizing the need for database restructuring and streamlining the development of new integrated information systems. The honeycomb model employs a highly secure hierarchical access control and permission system, allowing determination of data access privileges in a finely granular manner without flooding the security subsystem with a multiplicity of rules. HIVE infrastructure will allow engineers and scientists to perform NGS analysis in a manner that is both efficient and secure. HIVE is actively supported in public and private domains, and project collaborations are welcomed. Database URL: https://hive.biochemistry.gwu.edu. © The Author(s) 2016. Published by Oxford University Press.
Breaking and Fixing Origin-Based Access Control in Hybrid Web/Mobile Application Frameworks.
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 and explain why they are ineffectual. We then present NoFrak, a capability-based defense against fracking attacks. NoFrak is platform-independent, compatible with any framework and embedded browser, requires no changes to the code of the existing hybrid apps, and does not break their advertising-supported business model.
10 CFR 20.1602 - Control of access to very high radiation areas.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 1 2010-01-01 2010-01-01 false Control of access to very high radiation areas. 20.1602 Section 20.1602 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1602 Control of access to very high radiation areas...
10 CFR 20.1602 - Control of access to very high radiation areas.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 1 2013-01-01 2013-01-01 false Control of access to very high radiation areas. 20.1602 Section 20.1602 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1602 Control of access to very high radiation areas...
10 CFR 20.1602 - Control of access to very high radiation areas.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 1 2014-01-01 2014-01-01 false Control of access to very high radiation areas. 20.1602 Section 20.1602 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1602 Control of access to very high radiation areas...
10 CFR 20.1602 - Control of access to very high radiation areas.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 1 2011-01-01 2011-01-01 false Control of access to very high radiation areas. 20.1602 Section 20.1602 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1602 Control of access to very high radiation areas...
10 CFR 20.1602 - Control of access to very high radiation areas.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 1 2012-01-01 2012-01-01 false Control of access to very high radiation areas. 20.1602 Section 20.1602 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Control of Exposure From External Sources in Restricted Areas § 20.1602 Control of access to very high radiation areas...
How to mathematically optimize drug regimens using optimal control.
Moore, Helen
2018-02-01
This article gives an overview of a technique called optimal control, which is used to optimize real-world quantities represented by mathematical models. I include background information about the historical development of the technique and applications in a variety of fields. The main focus here is the application to diseases and therapies, particularly the optimization of combination therapies, and I highlight several such examples. I also describe the basic theory of optimal control, and illustrate each of the steps with an example that optimizes the doses in a combination regimen for leukemia. References are provided for more complex cases. The article is aimed at modelers working in drug development, who have not used optimal control previously. My goal is to make this technique more accessible in the biopharma community.
Improving School Access Control
ERIC Educational Resources Information Center
National Clearinghouse for Educational Facilities, 2008
2008-01-01
Few things are more important for school safety and security than controlling access to buildings and grounds. It is relatively easy to incorporate effective access control measures in new school designs but more difficult in existing schools, where most building and site features cannot be readily altered or reconfigured. The National…
77 FR 551 - Privacy Act of 1974; Amended System of Records
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-05
... Act system of records entitled ``Treasury/BEP .027--Access Control and Alarm Monitoring Systems (ACAMS... .027--Access Control and Alarm Monitoring Systems (ACAMS).'' BEP proposes to amend that system of... records entitled ``BEP .027--Access Control and Alarm Monitoring Systems (ACAMS),'' as follows: Treasury...
Queipo-Ortuño, María Isabel; Seoane, Luisa María; Murri, Mora; Pardo, María; Gomez-Zumaquero, Juan Miguel; Cardona, Fernando; Casanueva, Felipe; Tinahones, Francisco J
2013-01-01
Several evidences indicate that gut microbiota is involved in the control of host energy metabolism. To evaluate the differences in the composition of gut microbiota in rat models under different nutritional status and physical activity and to identify their associations with serum leptin and ghrelin levels. In a case control study, forty male rats were randomly assigned to one of these four experimental groups: ABA group with food restriction and free access to exercise; control ABA group with food restriction and no access to exercise; exercise group with free access to exercise and feed ad libitum and ad libitum group without access to exercise and feed ad libitum. The fecal bacteria composition was investigated by PCR-denaturing gradient gel electrophoresis and real-time qPCR. In restricted eaters, we have found a significant increase in the number of Proteobacteria, Bacteroides, Clostridium, Enterococcus, Prevotella and M. smithii and a significant decrease in the quantities of Actinobacteria, Firmicutes, Bacteroidetes, B. coccoides-E. rectale group, Lactobacillus and Bifidobacterium with respect to unrestricted eaters. Moreover, a significant increase in the number of Lactobacillus, Bifidobacterium and B. coccoides-E. rectale group was observed in exercise group with respect to the rest of groups. We also found a significant positive correlation between the quantity of Bifidobacterium and Lactobacillus and serum leptin levels, and a significant and negative correlation among the number of Clostridium, Bacteroides and Prevotella and serum leptin levels in all experimental groups. Furthermore, serum ghrelin levels were negatively correlated with the quantity of Bifidobacterium, Lactobacillus and B. coccoides-Eubacterium rectale group and positively correlated with the number of Bacteroides and Prevotella. Nutritional status and physical activity alter gut microbiota composition affecting the diversity and similarity. This study highlights the associations between gut microbiota and appetite-regulating hormones that may be important in terms of satiety and host metabolism.
Queipo-Ortuño, María Isabel; Seoane, Luisa María; Murri, Mora; Pardo, María; Gomez-Zumaquero, Juan Miguel; Cardona, Fernando; Casanueva, Felipe; Tinahones, Francisco J.
2013-01-01
Background Several evidences indicate that gut microbiota is involved in the control of host energy metabolism. Objective To evaluate the differences in the composition of gut microbiota in rat models under different nutritional status and physical activity and to identify their associations with serum leptin and ghrelin levels. Methods In a case control study, forty male rats were randomly assigned to one of these four experimental groups: ABA group with food restriction and free access to exercise; control ABA group with food restriction and no access to exercise; exercise group with free access to exercise and feed ad libitum and ad libitum group without access to exercise and feed ad libitum. The fecal bacteria composition was investigated by PCR-denaturing gradient gel electrophoresis and real-time qPCR. Results In restricted eaters, we have found a significant increase in the number of Proteobacteria, Bacteroides, Clostridium, Enterococcus, Prevotella and M. smithii and a significant decrease in the quantities of Actinobacteria, Firmicutes, Bacteroidetes, B. coccoides-E. rectale group, Lactobacillus and Bifidobacterium with respect to unrestricted eaters. Moreover, a significant increase in the number of Lactobacillus, Bifidobacterium and B. coccoides–E. rectale group was observed in exercise group with respect to the rest of groups. We also found a significant positive correlation between the quantity of Bifidobacterium and Lactobacillus and serum leptin levels, and a significant and negative correlation among the number of Clostridium, Bacteroides and Prevotella and serum leptin levels in all experimental groups. Furthermore, serum ghrelin levels were negatively correlated with the quantity of Bifidobacterium, Lactobacillus and B. coccoides–Eubacterium rectale group and positively correlated with the number of Bacteroides and Prevotella. Conclusions Nutritional status and physical activity alter gut microbiota composition affecting the diversity and similarity. This study highlights the associations between gut microbiota and appetite-regulating hormones that may be important in terms of satiety and host metabolism. PMID:23724144
36 CFR 1256.70 - What controls access to national security-classified information?
Code of Federal Regulations, 2010 CFR
2010-07-01
... national security-classified information? 1256.70 Section 1256.70 Parks, Forests, and Public Property... HISTORICAL MATERIALS Access to Materials Containing National Security-Classified Information § 1256.70 What controls access to national security-classified information? (a) The declassification of and public access...
Linking the Pilot Structural Model and Pilot Workload
NASA Technical Reports Server (NTRS)
Bachelder, Edward; Hess, Ronald; Aponso, Bimal; Godfroy-Cooper, Martine
2018-01-01
Behavioral models are developed that closely reproduced pulsive control response of two pilots using markedly different control techniques while conducting a tracking task. An intriguing find was that the pilots appeared to: 1) produce a continuous, internally-generated stick signal that they integrated in time; 2) integrate the actual stick position; and 3) compare the two integrations to either issue or cease a pulse command. This suggests that the pilots utilized kinesthetic feedback in order to sense and integrate stick position, supporting the hypothesis that pilots can access and employ the proprioceptive inner feedback loop proposed by Hess's pilot Structural Model. A Pilot Cost Index was developed, whose elements include estimated workload, performance, and the degree to which the pilot employs kinesthetic feedback. Preliminary results suggest that a pilot's operating point (parameter values) may be based on control style and index minimization.
Cervical Cancer Control for Hispanic Women in Texas: Effective Strategies from Research and Practice
Fernandez, Maria E.; Savas, Lara S.; Lipizzi, Erica; Smith, Jennifer S.; Vernon, Sally W.
2014-01-01
Purpose Hispanic women in Texas have among the highest rates of cervical cancer incidence and mortality in the country. Increasing regular Papanicolaou test screening and HPV vaccination are crucial to reduce the burden of cervical cancer among Hispanics. This paper presents lessons learned from community-based cervical cancer control programs in Texas and highlights effective intervention programs, methods and strategies. Methods We reviewed and summarized cervical cancer control efforts targeting Hispanic women in Texas, focusing on interventions developed by researchers at the University of Texas, School of Public Health. We identified commonalities across programs, highlighted effective methods, and summarized lessons learned to help guide future intervention efforts. Results Community-academic partnerships were fundamental in all steps of program development and implementation. Programs reviewed addressed psychosocial, cultural, and access barriers to cervical cancer control among low-income Hispanic women. Intervention approaches included lay health worker (LHW) and navigation models and used print media, interactive tailored media, photonovellas, client reminders, one-on-one and group education sessions. Conclusions Small media materials combined with LHW and navigation approaches were effective in delivering Pap test screening and HPV vaccination messages and in linking women to services. Common theoretical methods included in these approaches were modeling, verbal persuasion, and facilitating access. Adaptation of programs to an urban environment revealed that intensive navigation was needed to link women with multiple access barriers to health services. Collectively, this review reveals 1) the importance of using a systematic approach for planning and adapting cervical cancer control programs; 2) advantages of collaborative academic-community partnerships to develop feasible interventions with broad reach; 3) the use of small media and LHW approaches and the need for tailored phone navigation in urban settings; and 4) coordination and technical assistance of community-based efforts as a way to maximize resources. PMID:24398135
Modeling of the ground-to-SSFMB link networking features using SPW
NASA Technical Reports Server (NTRS)
Watson, John C.
1993-01-01
This report describes the modeling and simulation of the networking features of the ground-to-Space Station Freedom manned base (SSFMB) link using COMDISCO signal processing work-system (SPW). The networking features modeled include the implementation of Consultative Committee for Space Data Systems (CCSDS) protocols in the multiplexing of digitized audio and core data into virtual channel data units (VCDU's) in the control center complex and the demultiplexing of VCDU's in the onboard baseband signal processor. The emphasis of this work has been placed on techniques for modeling the CCSDS networking features using SPW. The objectives for developing the SPW models are to test the suitability of SPW for modeling networking features and to develop SPW simulation models of the control center complex and space station baseband signal processor for use in end-to-end testing of the ground-to-SSFMB S-band single access forward (SSAF) link.
Location Based Application Availability
NASA Astrophysics Data System (ADS)
Naeem Akram, Raja; Markantonakis, Konstantinos; Mayes, Keith
Smart cards are being integrated into a diverse range of industries: ranging from banking, telecom, transport, home/office access control to health and E-passport. Traditionally, cardholders are required to carry a smart card for each application. However, recent developments in the Near Field Communication (NFC) have renewed the interest in multiple applications for different services on a single device. This paper builds onto the NFC initiative and avoids the smart card ownership issues that hinder the adoption of such devices. The proposal integrates the Global Positioning System with the NFC in mobile phones to provide a ubiquitously and flexible service access model.
An approach for investigation of secure access processes at a combined e-learning environment
NASA Astrophysics Data System (ADS)
Romansky, Radi; Noninska, Irina
2017-12-01
The article discuses an approach to investigate processes for regulation the security and privacy control at a heterogenous e-learning environment realized as a combination of traditional and cloud means and tools. Authors' proposal for combined architecture of e-learning system is presented and main subsystems and procedures are discussed. A formalization of the processes for using different types resources (public, private internal and private external) is proposed. The apparatus of Markovian chains (MC) is used for modeling and analytical investigation of the secure access to the resources is used and some assessments are presented.
78 FR 16757 - Twentieth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-18
... Committee 224, Airport 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... meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...
77 FR 64838 - Sixteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-23
... Committee 224, Airport 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... meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...
77 FR 55894 - Fifteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-11
... Committee 224, Airport 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... meeting of the RTCA Special Committee 224, Airport Security Access Control Systems DATES: The meeting will...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-07-22
... Committee 224, Airport 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... meeting of the RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting...
Analysis of Access Control Policies in Operating Systems
ERIC Educational Resources Information Center
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…
Modular Aero-Propulsion System Simulation
NASA Technical Reports Server (NTRS)
Parker, Khary I.; Guo, Ten-Huei
2006-01-01
The Modular Aero-Propulsion System Simulation (MAPSS) is a graphical simulation environment designed for the development of advanced control algorithms and rapid testing of these algorithms on a generic computational model of a turbofan engine and its control system. MAPSS is a nonlinear, non-real-time simulation comprising a Component Level Model (CLM) module and a Controller-and-Actuator Dynamics (CAD) module. The CLM module simulates the dynamics of engine components at a sampling rate of 2,500 Hz. The controller submodule of the CAD module simulates a digital controller, which has a typical update rate of 50 Hz. The sampling rate for the actuators in the CAD module is the same as that of the CLM. MAPSS provides a graphical user interface that affords easy access to engine-operation, engine-health, and control parameters; is used to enter such input model parameters as power lever angle (PLA), Mach number, and altitude; and can be used to change controller and engine parameters. Output variables are selectable by the user. Output data as well as any changes to constants and other parameters can be saved and reloaded into the GUI later.
Data Services in Support of High Performance Computing-Based Distributed Hydrologic Models
NASA Astrophysics Data System (ADS)
Tarboton, D. G.; Horsburgh, J. S.; Dash, P. K.; Gichamo, T.; Yildirim, A. A.; Jones, N.
2014-12-01
We have developed web-based data services to support the application of hydrologic models on High Performance Computing (HPC) systems. The purposes of these services are to provide hydrologic researchers, modelers, water managers, and users access to HPC resources without requiring them to become HPC experts and understanding the intrinsic complexities of the data services, so as to reduce the amount of time and effort spent in finding and organizing the data required to execute hydrologic models and data preprocessing tools on HPC systems. These services address some of the data challenges faced by hydrologic models that strive to take advantage of HPC. Needed data is often not in the form needed by such models, requiring researchers to spend time and effort on data preparation and preprocessing that inhibits or limits the application of these models. Another limitation is the difficult to use batch job control and queuing systems used by HPC systems. We have developed a REST-based gateway application programming interface (API) for authenticated access to HPC systems that abstracts away many of the details that are barriers to HPC use and enhances accessibility from desktop programming and scripting languages such as Python and R. We have used this gateway API to establish software services that support the delineation of watersheds to define a modeling domain, then extract terrain and land use information to automatically configure the inputs required for hydrologic models. These services support the Terrain Analysis Using Digital Elevation Model (TauDEM) tools for watershed delineation and generation of hydrology-based terrain information such as wetness index and stream networks. These services also support the derivation of inputs for the Utah Energy Balance snowmelt model used to address questions such as how climate, land cover and land use change may affect snowmelt inputs to runoff generation. To enhance access to the time varying climate data used to drive hydrologic models, we have developed services to downscale and re-grid nationally available climate analysis data from systems such as NLDAS and MERRA. These cases serve as examples for how this approach can be extended to other models to enhance the use of HPC for hydrologic modeling.
Robust Informatics Infrastructure Required For ICME: Combining Virtual and Experimental Data
NASA Technical Reports Server (NTRS)
Arnold, Steven M.; Holland, Frederic A. Jr.; Bednarcyk, Brett A.
2014-01-01
With the increased emphasis on reducing the cost and time to market of new materials, the need for robust automated materials information management system(s) enabling sophisticated data mining tools is increasing, as evidenced by the emphasis on Integrated Computational Materials Engineering (ICME) and the recent establishment of the Materials Genome Initiative (MGI). This need is also fueled by the demands for higher efficiency in material testing; consistency, quality and traceability of data; product design; engineering analysis; as well as control of access to proprietary or sensitive information. Further, the use of increasingly sophisticated nonlinear, anisotropic and or multi-scale models requires both the processing of large volumes of test data and complex materials data necessary to establish processing-microstructure-property-performance relationships. Fortunately, material information management systems have kept pace with the growing user demands and evolved to enable: (i) the capture of both point wise data and full spectra of raw data curves, (ii) data management functions such as access, version, and quality controls;(iii) a wide range of data import, export and analysis capabilities; (iv) data pedigree traceability mechanisms; (v) data searching, reporting and viewing tools; and (vi) access to the information via a wide range of interfaces. This paper discusses key principles for the development of a robust materials information management system to enable the connections at various length scales to be made between experimental data and corresponding multiscale modeling toolsets to enable ICME. In particular, NASA Glenn's efforts towards establishing such a database for capturing constitutive modeling behavior for both monolithic and composites materials
2011-11-30
does not display a currently valid OMB control number. 1. REPORT DATE 30 NOV 2011 2. REPORT TYPE 3. DATES COVERED 00-00-2011 to 00-00-2011 4...Appropriate site variables (for purposes of accurate modeling); • Potential queues caused by the access control facility to the south parking...to LoS D LoS Control Delay/Vehicle (sec) Qualitative Description A ≤10 Good progression, few stops, and short cycle lengths B >10 - 20 Good
Theoretical and experimental aspects of chaos control by time-delayed feedback.
Just, Wolfram; Benner, Hartmut; Reibold, Ekkehard
2003-03-01
We review recent developments for the control of chaos by time-delayed feedback methods. While such methods are easily applied even in quite complex experimental context the theoretical analysis yields infinite-dimensional differential-difference systems which are hard to tackle. The essential ideas for a general theoretical approach are sketched and the results are compared to electronic circuits and to high power ferromagnetic resonance experiments. Our results show that the control performance can be understood on the basis of experimentally accessible quantities without resort to any model for the internal dynamics.
Shi, Leiyu; Lee, De-Chih; Liang, Hailun; Zhang, Luwen; Makinen, Marty; Blanchet, Nathan; Kidane, Ruth; Lindelow, Magnus; Wang, Hong; Wu, Shaolong
2015-11-30
Reform of the health care system in urban areas of China has prompted concerns about the utilization of Community Health Centers (CHC). This study examined which of the dominant primary care delivery models, i.e., the public CHC model, the 'gate-keeper' CHC model, or the hospital-owned CHC models, was most effective in enhancing access to and quality of care for patients with chronic illness. The case-comparison design was used to study nine health care organizations in Guangzhou, Dongguan, and Shenzhen cities within Guangdong province, China. 560 patients aged 50 or over with hypertension or diabetes who visited either CHCs or hospitals in these three cities were surveyed by using face-to-face interviews. Bivariate analyses were performed to compare quality and value of care indicators among subjects from the three cities. Multivariate analyses were used to assess the association between type of primary care delivery and quality as well as value of chronic care after controlling for patients' demographic and health status characteristics. Patients from all three cities chose their current health care providers primarily out of concern for quality of care (both provider expertise and adequate medical equipment), patient-centered care, and insurance plan requirement. Compared with patients from Guangzhou, those from Dongguan performed significantly better on most quality and value of care indicators. Most of these indicators remained significantly better even after controlling for patients' demographic and health status characteristics. The Shenzhen model (hospital-owned and -managed CHC) was generally effective in enhancing accessibility and continuity. However, coordination suffered due to seemingly duplicating primary care outpatients at the hospital setting. Significant associations between types of health care facilities and quality of care were also observed such that patients from CHCs were more likely to be satisfied with traveling time and follow-up care by their providers. The study suggested that the Dongguan model (based on insurance mandate and using family practice physicians as 'gate-keepers') seemed to work best in terms of improving access and quality for patients with chronic conditions. The study suggested adequately funded and well-organized primary care system can play a gatekeeping role and has the potential to provide a reasonable level of care to patients.
A Programming Language Supporting First-Class Parallel Environments
1989-01-01
Symmetric Lisp later in the thesis. 1.5.1.2 Procedures as Data - Comparison with Lisp Classical Lisp[48, 54] has been altered and extended in many ways... manangement problems. A resource manager controls access to one or more resources shared by concurrently executing processes. Database transaction systems...symmetric languages are related to languages based on more classical models? 3. What are the kinds of uniformity that the symmetric model supports and what
2015-03-16
shaded region around each total sensitivity value was the maximum uncertainty in that value estimated by the Sobol method. 2.4. Global Sensitivity...Performance We conducted a global sensitivity analysis, using the variance-based method of Sobol , to estimate which parameters controlled the...Hunter, J.D. Matplotlib: A 2D Graphics Environment. Comput. Sci. Eng. 2007, 9, 90–95. 69. Sobol , I. Global sensitivity indices for nonlinear
Enabling Flexible and Continuous Capability Invocation in Mobile Prosumer Environments
Alcarria, Ramon; Robles, Tomas; Morales, Augusto; López-de-Ipiña, Diego; Aguilera, Unai
2012-01-01
Mobile prosumer environments require the communication with heterogeneous devices during the execution of mobile services. These environments integrate sensors, actuators and smart devices, whose availability continuously changes. The aim of this paper is to design a reference architecture for implementing a model for continuous service execution and access to capabilities, i.e., the functionalities provided by these devices. The defined architecture follows a set of software engineering patterns and includes some communication paradigms to cope with the heterogeneity of sensors, actuators, controllers and other devices in the environment. In addition, we stress the importance of the flexibility in capability invocation by allowing the communication middleware to select the access technology and change the communication paradigm when dealing with smart devices, and by describing and evaluating two algorithms for resource access management. PMID:23012526
Frequency control of wind turbine in power system
NASA Astrophysics Data System (ADS)
Xu, Huawei
2018-06-01
In order to improve the stability of the overall frequency of the power system, automatic power generation control and secondary frequency adjustment were applied. Automatic power generation control was introduced into power generation planning. A dual-fed wind generator power regulation model suitable for secondary frequency regulation was established. The results showed that this method satisfied the basic requirements of frequency regulation control of large-scale wind power access power systems and improved the stability and reliability of power system operation. Therefore, this system frequency control method and strategy is relatively simple. The effect is significant. The system frequency can quickly reach a steady state. It is worth applying and promoting.
A knowledge-based system for controlling automobile traffic
NASA Technical Reports Server (NTRS)
Maravas, Alexander; Stengel, Robert F.
1994-01-01
Transportation network capacity variations arising from accidents, roadway maintenance activity, and special events as well as fluctuations in commuters' travel demands complicate traffic management. Artificial intelligence concepts and expert systems can be useful in framing policies for incident detection, congestion anticipation, and optimal traffic management. This paper examines the applicability of intelligent route guidance and control as decision aids for traffic management. Basic requirements for managing traffic are reviewed, concepts for studying traffic flow are introduced, and mathematical models for modeling traffic flow are examined. Measures for quantifying transportation network performance levels are chosen, and surveillance and control strategies are evaluated. It can be concluded that automated decision support holds great promise for aiding the efficient flow of automobile traffic over limited-access roadways, bridges, and tunnels.
Open versus Controlled-Access Data | Office of Cancer Genomics
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
Review of SDDOT's highway access control process
DOT National Transportation Integrated Search
2000-02-01
This report presents the results and recommendations of a review of the South Dakota Department of Transportation's (SDDOT's) highway access control process. This document presents recommendations that improve South Dakota's access policy. The docume...
DOT National Transportation Integrated Search
1974-06-01
The report presents a summary of a study conducted for the Transportation Systems Center of promising access control techniques which are applicable to an aeronautical satellite system. Several frequency division multiple access (FDMA) and time divis...
NASA Astrophysics Data System (ADS)
Coffman, Mitchell Ward
The purpose of this dissertation was to examine the relationship between student access to a computer at home and academic achievement. The 2009 National Assessment of Educational Progress (NAEP) dataset was probed using the National Data Explorer (NDE) to investigate correlations in the subsets of SES, Parental Education, Race, and Gender as it relates to access of a home computer and improved performance scores for U.S. public school grade 12 science students. A causal-comparative approach was employed seeking clarity on the relationship between home access and performance scores. The influence of home access cannot overcome the challenges students of lower SES face. The achievement gap, or a second digital divide, for underprivileged classes of students, including minorities does not appear to contract via student access to a home computer. Nonetheless, in tests for significance, statistically significant improvement in science performance scores was reported for those having access to a computer at home compared to those not having access. Additionally, regression models reported evidence of correlations between and among subsets of controls for the demographic factors gender, race, and socioeconomic status. Variability in these correlations was high; suggesting influence from unobserved factors may have more impact upon the dependent variable. Having access to a computer at home increases performance scores for grade 12 general science students of all races, genders and socioeconomic levels. However, the performance gap is roughly equivalent to the existing performance gap of the national average for science scores, suggesting little influence from access to a computer on academic achievement. The variability of scores reported in the regression analysis models reflects a moderate to low effect, suggesting an absence of causation. These statistical results are accurate and confirm the literature review, whereby having access to a computer at home and the predictor variables were found to have a significant impact on performance scores, although the data presented suggest computer access at home is less influential upon performance scores than poverty and its correlates.
Investigating the Spatial Dimension of Food Access.
Yenerall, Jackie; You, Wen; Hill, Jennie
2017-08-02
The purpose of this article is to investigate the sensitivity of food access models to a dataset's spatial distribution and the empirical definition of food access, which contributes to understanding the mixed findings of previous studies. Data was collected in the Dan River Region in the United States using a telephone survey for individual-level variables ( n = 784) and a store audit for the location of food retailers and grocery store quality. Spatial scanning statistics assessed the spatial distribution of obesity and detected a cluster of grocery stores overlapping with a cluster of obesity centered on a grocery store suggesting that living closer to a grocery store increased the likelihood of obesity. Logistic regression further examined this relationship while controlling for demographic and other food environment variables. Similar to the cluster analysis results, increased distance to a grocery store significantly decreased the likelihood of obesity in the urban subsample (average marginal effects, AME = -0.09, p -value = 0.02). However, controlling for grocery store quality nullified these results (AME = -0.12, p -value = 0.354). Our findings suggest that measuring grocery store accessibility as the distance to the nearest grocery store captures variability in the spatial distribution of the health outcome of interest that may not reflect a causal relationship between the food environment and health.
Investigating the Spatial Dimension of Food Access
Yenerall, Jackie; You, Wen
2017-01-01
The purpose of this article is to investigate the sensitivity of food access models to a dataset’s spatial distribution and the empirical definition of food access, which contributes to understanding the mixed findings of previous studies. Data was collected in the Dan River Region in the United States using a telephone survey for individual-level variables (n = 784) and a store audit for the location of food retailers and grocery store quality. Spatial scanning statistics assessed the spatial distribution of obesity and detected a cluster of grocery stores overlapping with a cluster of obesity centered on a grocery store suggesting that living closer to a grocery store increased the likelihood of obesity. Logistic regression further examined this relationship while controlling for demographic and other food environment variables. Similar to the cluster analysis results, increased distance to a grocery store significantly decreased the likelihood of obesity in the urban subsample (average marginal effects, AME = −0.09, p-value = 0.02). However, controlling for grocery store quality nullified these results (AME = −0.12, p-value = 0.354). Our findings suggest that measuring grocery store accessibility as the distance to the nearest grocery store captures variability in the spatial distribution of the health outcome of interest that may not reflect a causal relationship between the food environment and health. PMID:28767093
Health information security: a case study of three selected medical centers in iran.
Hajrahimi, Nafiseh; Dehaghani, Sayed Mehdi Hejazi; Sheikhtaheri, Abbas
2013-03-01
Health Information System (HIS) is considered a unique factor in improving the quality of health care activities and cost reduction, but today with the development of information technology and use of internet and computer networks, patients' electronic records and health information systems have become a source for hackers. This study aims at checking health information security of three selected medical centers in Iran using AHP fuzzy and TOPSIS compound model. To achieve that security measures were identified, based on the research literature and decision making matrix using experts' points of view. Among the 27 indicators, seven indicators were selected as effective indicators and Fuzzy AHP technique was used to determine the importance of security indicators. Based on the comparisons made between the three selected medical centers to assess the security of health information, it is concluded that Chamran hospital has the most acceptable level of security and attention in three indicators of "verification and system design, user access management, access control system", Al Zahra Hospital in two indicators of "access management and network access control" and Amin Hospital in "equipment safety and system design". In terms of information security, Chamran Hospital ranked first, Al-Zahra Hospital ranked second and Al- Zahra hospital has the third place.
A Framework for Translating a High Level Security Policy into Low Level Security Mechanisms
NASA Astrophysics Data System (ADS)
Hassan, Ahmed A.; Bahgat, Waleed M.
2010-01-01
Security policies have different components; firewall, active directory, and IDS are some examples of these components. Enforcement of network security policies to low level security mechanisms faces some essential difficulties. Consistency, verification, and maintenance are the major ones of these difficulties. One approach to overcome these difficulties is to automate the process of translation of high level security policy into low level security mechanisms. This paper introduces a framework of an automation process that translates a high level security policy into low level security mechanisms. The framework is described in terms of three phases; in the first phase all network assets are categorized according to their roles in the network security and relations between them are identified to constitute the network security model. This proposed model is based on organization based access control (OrBAC). However, the proposed model extend the OrBAC model to include not only access control policy but also some other administrative security policies like auditing policy. Besides, the proposed model enables matching of each rule of the high level security policy with the corresponding ones of the low level security policy. Through the second phase of the proposed framework, the high level security policy is mapped into the network security model. The second phase could be considered as a translation of the high level security policy into an intermediate model level. Finally, the intermediate model level is translated automatically into low level security mechanism. The paper illustrates the applicability of proposed approach through an application example.
An employer's experience with infertility coverage: a case study.
Silverberg, Kaylen; Meletiche, Dennis; Del Rosario, Gina
2009-12-01
A case study of Southwest Airlines, a Fortune 500 company, demonstrates that a well-designed infertility coverage plan can control resource use. This successful model could be used by employers who wish to ensure that their employees have access to high-quality, cost-effective infertility services in a managed-care environment.
Possibilities and Limitations of Cable TV for Adult Education.
ERIC Educational Resources Information Center
Niemi, John A.
The paper investigates various organizational models of cable TV ownership and control, legislation in Canada and the United States regarding cable systems, and the potential of cable as an information network for adult education. With a view to giving everyone access to the cable medium and an opportunity to participate, advantages and…
Openness, Web 2.0 Technology, and Open Science
ERIC Educational Resources Information Center
Peters, Michael A.
2010-01-01
Open science is a term that is being used in the literature to designate a form of science based on open source models or that utilizes principles of open access, open archiving and open publishing to promote scientific communication. Open science increasingly also refers to open governance and more democratized engagement and control of science…
2013-03-01
1989. Evaluation of the cotton fabric model for screening topical mosquito repellents . J Am Mosq Control Assoc 5:73–76. WHO [World Health Organization...institutions, research libraries, and research funders in the common goal of maximizing access to critical research. High-Throughput Mosquito and Fly Bioassay...A. Allan , Todd W. Walker , Christopher J. Geden , Jerome A. Hogsette , and Kenneth J. Linthicum Source: Journal of the American Mosquito Control
Progress in Guidance and Control Research for Space Access and Hypersonic Vehicles (Preprint)
2006-09-01
affect range capabilities. In 2003 an integrated adaptive guidance control and trajectory re- shaping algorithm was flight demonstrated using in-flight...21] which tied for the best scores as well as a Linear Quadratic Regulator[22], Predictor - Corrector [23], and Shuttle-like entry[24] guidance method...Accurate knowledge of mass, center- of-gravity and moments of inertia improves the perfor- mance of not only IAG& C algorithms but also model based
ERIC Educational Resources Information Center
Brandenburg, Sara A., Ed.; Vanderheiden, Gregg C., Ed.
One of a series of three resource guides concerned with communication, control, and computer access for disabled and elderly individuals, the directory focuses on switches and environmental controls. The book's three chapters each cover products with the same primary function. Cross reference indexes allow access to listings of products by…
Modeling livestock population structure: a geospatial database for Ontario swine farms.
Khan, Salah Uddin; O'Sullivan, Terri L; Poljak, Zvonimir; Alsop, Janet; Greer, Amy L
2018-01-30
Infectious diseases in farmed animals have economic, social, and health consequences. Foreign animal diseases (FAD) of swine are of significant concern. Mathematical and simulation models are often used to simulate FAD outbreaks and best practices for control. However, simulation outcomes are sensitive to the population structure used. Within Canada, access to individual swine farm population data with which to parameterize models is a challenge because of privacy concerns. Our objective was to develop a methodology to model the farmed swine population in Ontario, Canada that could represent the existing population structure and improve the efficacy of simulation models. We developed a swine population model based on the factors such as facilities supporting farm infrastructure, land availability, zoning and local regulations, and natural geographic barriers that could affect swine farming in Ontario. Assigned farm locations were equal to the swine farm density described in the 2011 Canadian Census of Agriculture. Farms were then randomly assigned to farm types proportional to the existing swine herd types. We compared the swine population models with a known database of swine farm locations in Ontario and found that the modeled population was representative of farm locations with a high accuracy (AUC: 0.91, Standard deviation: 0.02) suggesting that our algorithm generated a reasonable approximation of farm locations in Ontario. In the absence of a readily accessible dataset providing details of the relative locations of swine farms in Ontario, development of a model livestock population that captures key characteristics of the true population structure while protecting privacy concerns is an important methodological advancement. This methodology will be useful for individuals interested in modeling the spread of pathogens between farms across a landscape and using these models to evaluate disease control strategies.
A Web-Based Remote Access Laboratory Using SCADA
ERIC Educational Resources Information Center
Aydogmus, Z.; Aydogmus, O.
2009-01-01
The Internet provides an opportunity for students to access laboratories from outside the campus. This paper presents a Web-based remote access real-time laboratory using SCADA (supervisory control and data acquisition) control. The control of an induction motor is used as an example to demonstrate the effectiveness of this remote laboratory,…
ERIC Educational Resources Information Center
Antony, Laljith
2016-01-01
Failing to prevent leaks of confidential and proprietary information to unauthorized users from software applications is a major challenge that companies face. Access control policies defined in software applications with access control mechanisms are unable to prevent information leaks from software applications to unauthorized users. Role-based…
76 FR 67019 - Tenth Meeting: RTCA Special Committee 224, Airport Security Access Control
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-28
... 224, Airport Security Access Control AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 224, Airport Security Access Control. SUMMARY: The... (Pub. L. 92-463, 5 U.S.C., App.), notice is hereby given for a Special Committee 224, Airport Security...
Johnson, Don; Garcia-Blanco, Jose; Burgert, James; Fulton, Lawrence; Kadilak, Patrick; Perry, Katherine; Burke, Jeffrey
2015-09-01
Cardiopulmonary Resuscitation (CPR), defibrillation, and epinephrine administration are pillars of advanced cardiac life support (ACLS). Intraosseous (IO) access is an alternative route for epinephrine administration when intravenous (IV) access is unobtainable. Previous studies indicate the pharmacokinetics of epinephrine administration via IO and IV routes differ, but it is not known if the difference influences return of spontaneous circulation (ROSC). The purpose of this prospective, experimental study was to determine the effects of humeral IO (HIO) and IV epinephrine administration during cardiac arrest on pharmacokinetics, ROSC, and odds of survival. Swine (N = 21) were randomized into 3 groups: humeral IO (HIO), peripheral IV (IV) and CPR/defibrillation control. Cardiac arrest was induced under general anesthesia. The swine remained in arrest for 2 min without intervention. Chest compressions were initiated and continued for 2 min. Epinephrine was administered and serial blood samples collected for pharmacokinetic analysis over 4 min. Defibrillation and epinephrine administration proceeded according to ACLS guidelines continuing for 20 min or until ROSC. Seven HIO swine, 4 IV swine, and no control swine had ROSC. There were no significant differences in ROSC, maximum concentration; except at 30 s, and time-to-concentration-maximum between the HIO and IV groups. Significant differences existed between the experimental groups and the control. The HIO delivers a higher concentration of epinephrine than the IV route at 30 s which may be a survival advantage. Clinicians may consider using the IO route to administer epinephrine during CA when there is no preexisting IV access or when IV access is unobtainable.
Johnson, Don; Garcia-Blanco, Jose; Burgert, James; Fulton, Lawrence; Kadilak, Patrick; Perry, Katherine; Burke, Jeffrey
2015-01-01
Cardiopulmonary Resuscitation (CPR), defibrillation, and epinephrine administration are pillars of advanced cardiac life support (ACLS). Intraosseous (IO) access is an alternative route for epinephrine administration when intravenous (IV) access is unobtainable. Previous studies indicate the pharmacokinetics of epinephrine administration via IO and IV routes differ, but it is not known if the difference influences return of spontaneous circulation (ROSC). The purpose of this prospective, experimental study was to determine the effects of humeral IO (HIO) and IV epinephrine administration during cardiac arrest on pharmacokinetics, ROSC, and odds of survival. Swine (N = 21) were randomized into 3 groups: humeral IO (HIO), peripheral IV (IV) and CPR/defibrillation control. Cardiac arrest was induced under general anesthesia. The swine remained in arrest for 2 min without intervention. Chest compressions were initiated and continued for 2 min. Epinephrine was administered and serial blood samples collected for pharmacokinetic analysis over 4 min. Defibrillation and epinephrine administration proceeded according to ACLS guidelines continuing for 20 min or until ROSC. Seven HIO swine, 4 IV swine, and no control swine had ROSC. There were no significant differences in ROSC, maximum concentration; except at 30 s, and time-to-concentration-maximum between the HIO and IV groups. Significant differences existed between the experimental groups and the control. The HIO delivers a higher concentration of epinephrine than the IV route at 30 s which may be a survival advantage. Clinicians may consider using the IO route to administer epinephrine during CA when there is no preexisting IV access or when IV access is unobtainable. PMID:26468375
LaPelle, Nancy R; Luckmann, Roger; Simpson, E Hatheway; Martin, Elaine R
2006-01-01
Background Movement towards evidence-based practices in many fields suggests that public health (PH) challenges may be better addressed if credible information about health risks and effective PH practices is readily available. However, research has shown that many PH information needs are unmet. In addition to reviewing relevant literature, this study performed a comprehensive review of existing information resources and collected data from two representative PH groups, focusing on identifying current practices, expressed information needs, and ideal systems for information access. Methods Nineteen individual interviews were conducted among employees of two domains in a state health department – communicable disease control and community health promotion. Subsequent focus groups gathered additional data on preferences for methods of information access and delivery as well as information format and content. Qualitative methods were used to identify themes in the interview and focus group transcripts. Results Informants expressed similar needs for improved information access including single portal access with a good search engine; automatic notification regarding newly available information; access to best practice information in many areas of interest that extend beyond biomedical subject matter; improved access to grey literature as well as to more systematic reviews, summaries, and full-text articles; better methods for indexing, filtering, and searching for information; and effective ways to archive information accessed. Informants expressed a preference for improving systems with which they were already familiar such as PubMed and listservs rather than introducing new systems of information organization and delivery. A hypothetical ideal model for information organization and delivery was developed based on informants' stated information needs and preferred means of delivery. Features of the model were endorsed by the subjects who reviewed it. Conclusion Many critical information needs of PH practitioners are not being met efficiently or at all. We propose a dual strategy of: 1) promoting incremental improvements in existing information delivery systems based on the expressed preferences of the PH users of the systems and 2) the concurrent development and rigorous evaluation of new models of information organization and delivery that draw on successful resources already operating to deliver information to clinical medical practitioners. PMID:16597331
Hamlet, Jason R [Albuquerque, NM; Robertson, Perry J [Albuquerque, NM; Pierson, Lyndon G [Albuquerque, NM; Olsberg, Ronald R [Albuquerque, NM
2012-02-28
A deflate decompressor includes at least one decompressor unit, a memory access controller, a feedback path, and an output buffer unit. The memory access controller is coupled to the decompressor unit via a data path and includes a data buffer to receive the data stream and temporarily buffer a first portion the data stream. The memory access controller transfers fixed length data units of the data stream from the data buffer to the decompressor unit with reference to a memory pointer pointing into the memory buffer. The feedback path couples the decompressor unit to the memory access controller to feed back decrement values to the memory access controller for updating the memory pointer. The decrement values each indicate a number of bits unused by the decompressor unit when decoding the fixed length data units. The output buffer unit buffers a second portion of the data stream after decompression.
Shah, Rahman; Askari, Reza; Haji, Showkat A; Rashid, Abdul
2017-12-01
Recently, several meta-analyses of randomized controlled trials (RCTs) have shown that transradial access (TRA) reduces mortality compared to transfemoral access (TFA). However, a critical appraisal of these RCTs suggests that the findings could have resulted from a greater incidence of adverse events in the TFA groups rather than a beneficial effect of TRA. Scientific databases and websites were searched for RCTs. Patients were divided into groups based on access type and whether the operator was a radial expert (RE) or non-radial expert (NRE). The groups were TFA-RE, TFA-NRE, TRA-RE, and TRA-NRE. Both a traditional meta-analysis and a network meta-analysis using mixed-treatment comparison models were performed. Data from 13 trials including 15,615 patients were analyzed. The mortality rate for TFA-RE (3.54%) was more than double compared to TFA-NRE (1.61%). In pairwise meta-analysis, TFA-RE was associated with increased risk of mortality (RR: 1.72, 95% CI: 1.13-2.62; p=0.011) compared to TFA-NRE. In subgroup analysis, TFA-RE was associated with increased mortality (RR: 1.70, 95% CI: 1.24-2.34; p=0.001) compared to TRA, but TRA-NRE was not. Similarly, in mixed comparison models, TFA-RE was associated with increased mortality compared to TRA-NRE, TRA-RE, and TFA-NRE, but TFA-NRE was not, compared to TRA-RE and TRA-NRE. Recently-reported survival differences between TRA and TFA may have been driven by adverse events in the TFA groups of the RCTs rather than a beneficial effect of TRA. This issue needs further investigation before labeling radial access a lifesaving procedure in invasively-managed patients with ACS. Published by Elsevier B.V.
Rational Modular RNA Engineering Based on In Vivo Profiling of Structural Accessibility.
Leistra, Abigail N; Amador, Paul; Buvanendiran, Aishwarya; Moon-Walker, Alex; Contreras, Lydia M
2017-12-15
Bacterial small RNAs (sRNAs) have been established as powerful parts for controlling gene expression. However, development and application of engineered sRNAs has primarily focused on regulating novel synthetic targets. In this work, we demonstrate a rational modular RNA engineering approach that uses in vivo structural accessibility measurements to tune the regulatory activity of a multisubstrate sRNA for differential control of its native target network. Employing the CsrB global sRNA regulator as a model system, we use published in vivo structural accessibility data to infer the contribution of its local structures (substructures) to function and select a subset for engineering. We then modularly recombine the selected substructures, differentially representing those of presumed high or low functional contribution, to build a library of 21 CsrB variants. Using fluorescent translational reporter assays, we demonstrate that the CsrB variants achieve a 5-fold gradient of control of well-characterized Csr network targets. Interestingly, results suggest that less conserved local structures within long, multisubstrate sRNAs may represent better targets for rational engineering than their well-conserved counterparts. Lastly, mapping the impact of sRNA variants on a signature Csr network phenotype indicates the potential of this approach for tuning the activity of global sRNA regulators in the context of metabolic engineering applications.
Khater, Nazih; Shen, Jim; Arenas, Javier; Keheila, Mohamed; Alsyouf, Muhannad; Martin, Jacob A; Lightfoot, Michelle A; Li, Roger; Olgin, Gaudencio; Smith, Jason C; Baldwin, D Duane
2016-11-01
Traditional techniques for obtaining percutaneous renal access utilize continuous fluoroscopy. In an attempt to minimize radiation exposure, we describe a novel laser direct alignment radiation reduction technique (DARRT) for percutaneous access and test it in a bench-top model. In this randomized-controlled bench-top study, 20 medical personnel obtained renal accesses using both the conventional bullseye technique and the laser DARRT. The primary endpoint was total fluoroscopy time. Secondary endpoints included insertion time, puncture attempts, course corrections, and subjective procedural difficulty. In the laser DARRT, fluoroscopy was used with the C-arm positioned with the laser beam at a 30° angle. The access needle and hub were aligned with the laser beam. Effective caliceal puncture was confirmed with fluoroscopy and direct vision. The Paired samples Wilcoxon signed rank test was used for statistical analysis with significance at p < 0.05. A total of 120 needle placements were recorded. Fluoroscopy time for needle access using the laser DARRT was significantly lower than the bullseye technique in all groups as follows: attendings (7.09 vs 18.51 seconds; p < 0.001), residents (6.55 vs 13.93 seconds; p = 0.001), and medical students (6.69 vs 20.22 seconds; p < 0.001). Students rated the laser DARRT easier to use (2.56 vs 4.89; p < 0.001). No difference was seen in total access time, puncture attempts, or course corrections between techniques. The laser DARRT reduced fluoroscopy time by 63%, compared with the conventional bullseye technique. The least experienced users found the laser DARRT significantly easier to learn. This novel technique is promising and merits additional testing in animal and human models.
Unified Information Access in Product Creation with an Integrated Control Desk
NASA Astrophysics Data System (ADS)
Wrasse, Kevin; Diener, Holger; Hayka, Haygazun; Stark, Rainer
2017-06-01
Customers demand for individualized products leads to a large variety of different products in small series and single-unit production. A high flexibility pressure in product creation is one result of this trend. In order to counteract the pressure, the information steadily increasing by Industry 4.0 must be made available at the workplace. Additionally, a better exchange of information between product development, production planning and production is necessary. The improvement of individual systems, like CAD, PDM, ERP and MES, can only achieve this to a limited extent. Since they mostly use systems from different manufacturers, the necessary deeper integration of information is only feasible for SMEs to a limited extend. The presented control desk helps to ensure a more flexible product creation as well as information exchange. It captures information from different IT systems in the production process and presents them integrated, task-oriented and oriented to the user’s mental model, e.g. information of the production combined with the 3D model of product parts, or information about product development on the 3D model of the production. The solution is a digital 3D model of the manufacturing environment, which is enriched by billboards for a quick information overview and web service windows to access detailed MES and PDM information. By this, the level of abstraction can be reduced and reacts to changed requirements in the short term, making informed decisions. The interaction with the control stands utilizes the touch skills of mobile and fixed systems such as smartphones, tablets and multitouch tables.
Method for Evaluation of Outage Probability on Random Access Channel in Mobile Communication Systems
NASA Astrophysics Data System (ADS)
Kollár, Martin
2012-05-01
In order to access the cell in all mobile communication technologies a so called random-access procedure is used. For example in GSM this is represented by sending the CHANNEL REQUEST message from Mobile Station (MS) to Base Transceiver Station (BTS) which is consequently forwarded as an CHANNEL REQUIRED message to the Base Station Controller (BSC). If the BTS decodes some noise on the Random Access Channel (RACH) as random access by mistake (so- called ‘phantom RACH') then it is a question of pure coincidence which èstablishment cause’ the BTS thinks to have recognized. A typical invalid channel access request or phantom RACH is characterized by an IMMEDIATE ASSIGNMENT procedure (assignment of an SDCCH or TCH) which is not followed by sending an ESTABLISH INDICATION from MS to BTS. In this paper a mathematical model for evaluation of the Power RACH Busy Threshold (RACHBT) in order to guaranty in advance determined outage probability on RACH is described and discussed as well. It focuses on Global System for Mobile Communications (GSM) however the obtained results can be generalized on remaining mobile technologies (
Boisson, Sophie; Willis, Rebecca; Bakhtiari, Ana; al-Khatib, Tawfik; Amer, Khaled; Batcho, Wilfrid; Courtright, Paul; Dejene, Michael; Goepogui, Andre; Kalua, Khumbo; Kebede, Biruck; Macleod, Colin K.; Madeleine, Kouakou IIunga Marie; Mbofana, Mariamo Saide Abdala; Mpyet, Caleb; Ndjemba, Jean; Olobio, Nicholas; Pavluck, Alexandre L.; Sokana, Oliver; Southisombath, Khamphoua; Taleo, Fasihah
2018-01-01
Background Facial cleanliness and sanitation are postulated to reduce trachoma transmission, but there are no previous data on community-level herd protection thresholds. We characterize associations between active trachoma, access to improved sanitation facilities, and access to improved water sources for the purpose of face washing, with the aim of estimating community-level or herd protection thresholds. Methods and findings We used cluster-sampled Global Trachoma Mapping Project data on 884,850 children aged 1–9 years from 354,990 households in 13 countries. We employed multivariable mixed-effects modified Poisson regression models to assess the relationships between water and sanitation coverage and trachomatous inflammation—follicular (TF). We observed lower TF prevalence among those with household-level access to improved sanitation (prevalence ratio, PR = 0.87; 95%CI: 0.83–0.91), and household-level access to an improved washing water source in the residence/yard (PR = 0.81; 95%CI: 0.75–0.88). Controlling for household-level water and latrine access, we found evidence of community-level protection against TF for children living in communities with high sanitation coverage (PR80–90% = 0.87; 95%CI: 0.73–1.02; PR90–100% = 0.76; 95%CI: 0.67–0.85). Community sanitation coverage levels greater than 80% were associated with herd protection against TF (PR = 0.77; 95%CI: 0.62–0.97)—that is, lower TF in individuals whose households lacked individual sanitation but who lived in communities with high sanitation coverage. For community-level water coverage, there was no apparent threshold, although we observed lower TF among several of the higher deciles of community-level water coverage. Conclusions Our study provides insights into the community water and sanitation coverage levels that might be required to best control trachoma. Our results suggest access to adequate water and sanitation can be important components in working towards the 2020 target of eliminating trachoma as a public health problem. PMID:29357365
Fertility Effects of Abortion and Birth Control Pill Access for Minors
GULDI, MELANIE
2008-01-01
This article empirically assesses whether age-restricted access to abortion and the birth control pill influence minors’ fertility in the United States. There is not a strong consensus in previous literature regarding the relationship between laws restricting minors’ access to abortion and minors’ birthrates. This is the first study to recognize that state laws in place prior to the 1973 Roe v. Wade decision enabled minors to legally consent to surgical treatment—including abortion—in some states but not in others, and to construct abortion access variables reflecting this. In this article, age-specific policy variables measure either a minor’s legal ability to obtain an abortion or to obtain the birth control pill without parental involvement. I find fairly strong evidence that young women’s birthrates dropped as a result of abortion access as well as evidence that birth control pill access led to a drop in birthrates among whites. PMID:19110899
Fertility effects of abortion and birth control pill access for minors.
Guldi, Melanie
2008-11-01
This article empirically assesses whether age-restricted access to abortion and the birth control pill influence minors' fertility in the United States. There is not a strong consensus in previous literature regarding the relationship between laws restricting minors' access to abortion and minors' birth rates. This is the first study to recognize that state laws in place prior to the 1973 Roe v. Wade decision enabled minors to legally consent to surgical treatment-including abortion-in some states but not in others, and to construct abortion access variables reflecting this. In this article, age-specific policy variables measure either a minor's legal ability to obtain an abortion or to obtain the birth control pill without parental involvement. I find fairly strong evidence that young women's birth rates dropped as a result of abortion access as well as evidence that birth control pill access led to a drop in birth rates among whites.
Modeling spatial accessibility of immigrants to culturally diverse family physicians.
Wanga, Lu; Roisman, Deborah
2011-01-01
This article uses accessibility as an analytical tool to examine health care access among immigrants in a multicultural urban setting. It applies and improves on two widely used accessibility models—the gravity model and the two-step floating catchment area model—in measuring spatial accessibility by Mainland Chinese immigrants in the Toronto Census Metropolitan Area. Empirical data on physician-seeking behaviors are collected through two rounds of questionnaire surveys. Attention is focused on journey to physician location and utilization of linguistically matched family physicians. Based on the survey data, a two-zone accessibility model is developed by relaxing the travel threshold and distance impedance parameters that are traditionally treated as a constant in the accessibility models. General linear models are used to identify relationships among spatial accessibility, geography, and socioeconomic characteristics of Mainland Chinese immigrants. The results suggest a spatial mismatch in the supply of and demand for culturally sensitive care, and residential location is the primary factor that determines spatial accessibility to family physicians. The article yields important policy implications.
Blakeman, Tom; Blickem, Christian; Kennedy, Anne; Reeves, David; Bower, Peter; Gaffney, Hannah; Gardner, Caroline; Lee, Victoria; Jariwala, Praksha; Dawson, Shoba; Mossabir, Rahena; Brooks, Helen; Richardson, Gerry; Spackman, Eldon; Vassilev, Ivaylo; Chew-Graham, Carolyn; Rogers, Anne
2014-01-01
Background Implementation of self-management support in traditional primary care settings has proved difficult, encouraging the development of alternative models which actively link to community resources. Chronic kidney disease (CKD) is a common condition usually diagnosed in the presence of other co-morbidities. This trial aimed to determine the effectiveness of an intervention to provide information and telephone-guided access to community support versus usual care for patients with stage 3 CKD. Methods and Findings In a pragmatic, two-arm, patient level randomised controlled trial 436 patients with a diagnosis of stage 3 CKD were recruited from 24 general practices in Greater Manchester. Patients were randomised to intervention (215) or usual care (221). Primary outcome measures were health related quality of life (EQ-5D health questionnaire), blood pressure control, and positive and active engagement in life (heiQ) at 6 months. At 6 months, mean health related quality of life was significantly higher for the intervention group (adjusted mean difference = 0.05; 95% CI = 0.01, 0.08) and blood pressure was controlled for a significantly greater proportion of patients in the intervention group (adjusted odds-ratio = 1.85; 95% CI = 1.25, 2.72). Patients did not differ significantly in positive and active engagement in life. The intervention group reported a reduction in costs compared with control. Conclusions An intervention to provide tailored information and telephone-guided access to community resources was associated with modest but significant improvements in health related quality of life and better maintenance of blood pressure control for patients with stage 3 CKD compared with usual care. However, further research is required to identify the mechanisms of action of the intervention. Trial Registration Controlled-Trials.com ISRCTN45433299 PMID:25330169
Hanna, Timothy P; Kangolle, Alfred C T
2010-10-13
Cancer is a rapidly increasing problem in developing countries. Access, quality and efficiency of cancer services in developing countries must be understood to advance effective cancer control programs. Health services research can provide insights into these areas. This article provides an overview of oncology health services in developing countries. We use selected examples from peer-reviewed literature in health services research and relevant publicly available documents. In spite of significant limitations in the available data, it is clear there are substantial barriers to access to cancer control in developing countries. This includes prevention, early detection, diagnosis/treatment and palliation. There are also substantial limitations in the quality of cancer control and a great need to improve economic efficiency. We describe how the application of health data may assist in optimizing (1) Structure: strengthening planning, collaboration, transparency, research development, education and capacity building. (2) PROCESS: enabling follow-up, knowledge translation, patient safety and quality assurance. (3) OUTCOME: facilitating evaluation, monitoring and improvement of national cancer control efforts. There is currently limited data and capacity to use this data in developing countries for these purposes. There is an urgent need to improve health services for cancer control in developing countries. Current resources and much-needed investments must be optimally managed. To achieve this, we would recommend investment in four key priorities: (1) Capacity building in oncology health services research, policy and planning relevant to developing countries. (2) Development of high-quality health data sources. (3) More oncology-related economic evaluations in developing countries. (4) Exploration of high-quality models of cancer control in developing countries. Meeting these needs will require national, regional and international collaboration as well as political leadership. Horizontal integration with programs for other diseases will be important.
Sensorless Estimation and Nonlinear Control of a Rotational Energy Harvester
NASA Astrophysics Data System (ADS)
Nunna, Kameswarie; Toh, Tzern T.; Mitcheson, Paul D.; Astolfi, Alessandro
2013-12-01
It is important to perform sensorless monitoring of parameters in energy harvesting devices in order to determine the operating states of the system. However, physical measurements of these parameters is often a challenging task due to the unavailability of access points. This paper presents, as an example application, the design of a nonlinear observer and a nonlinear feedback controller for a rotational energy harvester. A dynamic model of a rotational energy harvester with its power electronic interface is derived and validated. This model is then used to design a nonlinear observer and a nonlinear feedback controller which yield a sensorless closed-loop system. The observer estimates the mechancial quantities from the measured electrical quantities while the control law sustains power generation across a range of source rotation speeds. The proposed scheme is assessed through simulations and experiments.
Stably accessing octave-spanning microresonator frequency combs in the soliton regime.
Li, Qing; Briles, Travis C; Westly, Daron A; Drake, Tara E; Stone, Jordan R; Ilic, B Robert; Diddams, Scott A; Papp, Scott B; Srinivasan, Kartik
2017-02-01
Microresonator frequency combs can be an enabling technology for optical frequency synthesis and timekeeping in low size, weight, and power architectures. Such systems require comb operation in low-noise, phase-coherent states such as solitons, with broad spectral bandwidths (e.g., octave-spanning) for self-referencing to detect the carrier-envelope offset frequency. However, accessing such states is complicated by thermo-optic dispersion. For example, in the Si 3 N 4 platform, precisely dispersion-engineered structures can support broadband operation, but microsecond thermal time constants often require fast pump power or frequency control to stabilize the solitons. In contrast, here we consider how broadband soliton states can be accessed with simple pump laser frequency tuning, at a rate much slower than the thermal dynamics. We demonstrate octave-spanning soliton frequency combs in Si 3 N 4 microresonators, including the generation of a multi-soliton state with a pump power near 40 mW and a single-soliton state with a pump power near 120 mW. We also develop a simplified two-step analysis to explain how these states are accessed without fast control of the pump laser, and outline the required thermal properties for such operation. Our model agrees with experimental results as well as numerical simulations based on a Lugiato-Lefever equation that incorporates thermo-optic dispersion. Moreover, it also explains an experimental observation that a member of an adjacent mode family on the red-detuned side of the pump mode can mitigate the thermal requirements for accessing soliton states.
Dowrick, Christopher; Bower, Peter; Chew-Graham, Carolyn; Lovell, Karina; Edwards, Suzanne; Lamb, Jonathan; Bristow, Katie; Gabbay, Mark; Burroughs, Heather; Beatty, Susan; Waheed, Waquas; Hann, Mark; Gask, Linda
2016-02-17
Many people with mental distress are disadvantaged because care is not available or does not address their needs. In order to increase access to high quality primary mental health care for under-served groups, we created a model of care with three discrete elements: community engagement, primary care training and tailored wellbeing interventions. We have previously demonstrated the individual impact of each element of the model. Here we assess the effectiveness of the combined model in increasing access to and improving the quality of primary mental health care. We test the assumptions that access to the wellbeing interventions is increased by the presence of community engagement and primary care training; and that quality of primary mental health care is increased by the presence of community engagement and the wellbeing interventions. We implemented the model in four under-served localities in North-West England, focusing on older people and minority ethnic populations. Using a quasi-experimental design with no-intervention comparators, we gathered a combination of quantitative and qualitative information. Quantitative information, including referral and recruitment rates for the wellbeing interventions, and practice referrals to mental health services, was analysed descriptively. Qualitative information derived from interview and focus group responses to topic guides from more than 110 participants. Framework analysis was used to generate findings from the qualitative data. Access to the wellbeing interventions was associated with the presence of the community engagement and the primary care training elements. Referrals to the wellbeing interventions were associated with community engagement, while recruitment was associated with primary care training. Qualitative data suggested that the mechanisms underlying these associations were increased awareness and sense of agency. The quality of primary mental health care was enhanced by information gained from our community mapping activities, and by the offer of access to the wellbeing interventions. There were variable benefits from health practitioner participation in community consultative groups. We also found that participation in the wellbeing interventions led to increased community engagement. We explored the interactions between elements of a multilevel intervention and identified important associations and underlying mechanisms. Further research is needed to test the generalisability of the model. Current Controlled Trials, reference ISRCTN68572159 . Registered 25 February 2013.
Engelhardt, Christopher R; Mazurek, Micah O
2014-07-01
Environmental correlates of problem behavior among individuals with autism spectrum disorder remain relatively understudied. The current study examined the contribution of in-room (i.e. bedroom) access to a video game console as one potential correlate of problem behavior among a sample of 169 boys with autism spectrum disorder (ranging from 8 to 18 years of age). Parents of these children reported on (1) whether they had specific rules regulating their child's video game use, (2) whether their child had in-room access to a variety of screen-based media devices (television, computer, and video game console), and (3) their child's oppositional behaviors. Multivariate regression models showed that in-room access to a video game console predicted oppositional behavior while controlling for in-room access to other media devices (computer and television) and relevant variables (e.g. average number of video game hours played per day). Additionally, the association between in-room access to a video game console and oppositional behavior was particularly large when parents reported no rules on their child's video game use. The current findings indicate that both access and parental rules regarding video games warrant future experimental and longitudinal research as they relate to problem behavior in boys with autism spectrum disorder. © The Author(s) 2013.
50 CFR 648.262 - Effort-control program for red crab limited access vessels.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Effort-control program for red crab... UNITED STATES Management Measures for the Atlantic Deep-Sea Red Crab Fishery § 648.262 Effort-control program for red crab limited access vessels. (a) General. A vessel issued a limited access red crab permit...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-02
... will have expanded access to Pell grants; or (2) a control group, which will not have access. Within both substudies, the treatment group will be very similar to the control at the time of random... between treatment and control group members can then be attributed to Pell grant access. The first...
Report #2006-P-00005, December 14, 2005. Controls needed to be improved in areas such as visitor access to facilities, use of contractor access badges, and general physical access to the NCC, computer rooms outside the NCC, and media storage rooms.
Aircraft Material Fire Test Handbook
1990-09-01
becomes extinguished for any period that exceeds 3 sec. A circuit for a satisfactory device is sketched in Figure 5-4. 5.3.8.2 Upper Pilot Burner An...34A model 470 Series Power controller manufactured by Eurotherm, a Model 3AEV 1B IOC I Triac manufactured by General Electric Co, or equivalent have...Compartment (galley or lavatory module ) An enclosure or shell structure with access provisions, such as a waste chute opening or doors, designed for
Tunable Superfluidity and Quantum Magnetism with Ultracold Polar Molecules
2011-09-08
generalization of the t-J model that we refer to as the anisotropic t-J-V-W model. Dipole-dipole interactions that give rise to this model are orders...controlled by the ratio between the Rabi frequency and the detuning of a þ-polarized microwave field acting on the j0i j1i tran- sition [27]. In 40K87Rb...field coupling jm0i and jm1i and performing an adiabatic passage from an easily accessible state to the desired ground state by tuning the Rabi
Experience with ActiveX control for simple channel access
DOE Office of Scientific and Technical Information (OSTI.GOV)
Timossi, C.; Nishimura, H.; McDonald, J.
2003-05-15
Accelerator control system applications at Berkeley Lab's Advanced Light Source (ALS) are typically deployed on operator consoles running Microsoft Windows 2000 and utilize EPICS[2]channel access for data access. In an effort to accommodate the wide variety of Windows based development tools and developers with little experience in network programming, ActiveX controls have been deployed on the operator stations. Use of ActiveX controls for use in the accelerator control environment has been presented previously[1]. Here we report on some of our experiences with the use and development of these controls.
49 CFR 1542.207 - Access control systems.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Transportation Other Regulations Relating to Transportation (Continued) TRANSPORTATION SECURITY ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Operations § 1542.207 Access control... original access medium, if the airport operator follows measures and procedures in the security program...
49 CFR 1542.207 - Access control systems.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Transportation Other Regulations Relating to Transportation (Continued) TRANSPORTATION SECURITY ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Operations § 1542.207 Access control... original access medium, if the airport operator follows measures and procedures in the security program...
49 CFR 1542.207 - Access control systems.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Transportation Other Regulations Relating to Transportation (Continued) TRANSPORTATION SECURITY ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Operations § 1542.207 Access control... original access medium, if the airport operator follows measures and procedures in the security program...
49 CFR 1542.207 - Access control systems.
Code of Federal Regulations, 2011 CFR
2011-10-01
... Transportation Other Regulations Relating to Transportation (Continued) TRANSPORTATION SECURITY ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Operations § 1542.207 Access control... original access medium, if the airport operator follows measures and procedures in the security program...
49 CFR 1542.207 - Access control systems.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Transportation Other Regulations Relating to Transportation (Continued) TRANSPORTATION SECURITY ADMINISTRATION, DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Operations § 1542.207 Access control... original access medium, if the airport operator follows measures and procedures in the security program...
Strohäker, Tanja; Becker, Tilman
2018-02-28
An exclusion system for gambling arcades has been introduced recently in the state of Hesse. The aim of this paper is to identify significant predictors that are useful in explaining the variation of exclusions between different Hessian communities. Next to socio-demographic factors, we control for three different accessibility variables in two models: the number of electronic gambling machines (EGMs) in model I, and the number of locations and density of gambling machines at a location in model II. We disentangle the association between EGMs and exclusions of model I into a location and a clustering effect. Considering the socio-demographic variables, the explanatory power of our cross-sectional models is rather low. Only the age group of the 30-39 years old and those who are not in a partnership (in model I) yield significant results. As self-exclusion systems reduce availability for the group of vulnerable players, this analysis provides evidence for the assumption that the two groups-pathological gamblers and vulnerable players-seem to have little overlap concerning sociodemographic characteristics. The accessibility variables, on the other hand, turn out to be significantly associated with the number of exclusions. All three of them are statistically significant and their association is positive. The results of model II show that the location effect is more pronounced then the clustering effect of EGMs, i.e. the effect of an additional single-licensed arcade on the number of exclusions is stronger than the increase in the number of license at one location.
NCPP's Use of Standard Metadata to Promote Open and Transparent Climate Modeling
NASA Astrophysics Data System (ADS)
Treshansky, A.; Barsugli, J. J.; Guentchev, G.; Rood, R. B.; DeLuca, C.
2012-12-01
The National Climate Predictions and Projections (NCPP) Platform is developing comprehensive regional and local information about the evolving climate to inform decision making and adaptation planning. This includes both creating and providing tools to create metadata about the models and processes used to create its derived data products. NCPP is using the Common Information Model (CIM), an ontology developed by a broad set of international partners in climate research, as its metadata language. This use of a standard ensures interoperability within the climate community as well as permitting access to the ecosystem of tools and services emerging alongside the CIM. The CIM itself is divided into a general-purpose (UML & XML) schema which structures metadata documents, and a project or community-specific (XML) Controlled Vocabulary (CV) which constraints the content of metadata documents. NCPP has already modified the CIM Schema to accommodate downscaling models, simulations, and experiments. NCPP is currently developing a CV for use by the downscaling community. Incorporating downscaling into the CIM will lead to several benefits: easy access to the existing CIM Documents describing CMIP5 models and simulations that are being downscaled, access to software tools that have been developed in order to search, manipulate, and visualize CIM metadata, and coordination with national and international efforts such as ES-DOC that are working to make climate model descriptions and datasets interoperable. Providing detailed metadata descriptions which include the full provenance of derived data products will contribute to making that data (and, the models and processes which generated that data) more open and transparent to the user community.
Performance Analysis of the IEEE 802.11p Multichannel MAC Protocol in Vehicular Ad Hoc Networks
2017-01-01
Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. The safety applications require timely and reliable transmissions, while the non-safety applications require efficient and high throughput. In the IEEE 1609.4 protocol, operating interval is divided into alternating Control Channel (CCH) interval and Service Channel (SCH) interval with an identical length. During the CCH interval, nodes transmit safety-related messages and control messages, and Enhanced Distributed Channel Access (EDCA) mechanism is employed to allow four Access Categories (ACs) within a station with different priorities according to their criticality for the vehicle’s safety. During the SCH interval, the non-safety massages are transmitted. An analytical model is proposed in this paper to evaluate performance, reliability and efficiency of the IEEE 802.11p and IEEE 1609.4 protocols. The proposed model improves the existing work by taking serval aspects and the character of multichannel switching into design consideration. Extensive performance evaluations based on analysis and simulation help to validate the accuracy of the proposed model and analyze the capabilities and limitations of the IEEE 802.11p and IEEE 1609.4 protocols, and enhancement suggestions are given. PMID:29231882
Performance Analysis of the IEEE 802.11p Multichannel MAC Protocol in Vehicular Ad Hoc Networks.
Song, Caixia
2017-12-12
Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. The safety applications require timely and reliable transmissions, while the non-safety applications require efficient and high throughput. In the IEEE 1609.4 protocol, operating interval is divided into alternating Control Channel (CCH) interval and Service Channel (SCH) interval with an identical length. During the CCH interval, nodes transmit safety-related messages and control messages, and Enhanced Distributed Channel Access (EDCA) mechanism is employed to allow four Access Categories (ACs) within a station with different priorities according to their criticality for the vehicle's safety. During the SCH interval, the non-safety massages are transmitted. An analytical model is proposed in this paper to evaluate performance, reliability and efficiency of the IEEE 802.11p and IEEE 1609.4 protocols. The proposed model improves the existing work by taking serval aspects and the character of multichannel switching into design consideration. Extensive performance evaluations based on analysis and simulation help to validate the accuracy of the proposed model and analyze the capabilities and limitations of the IEEE 802.11p and IEEE 1609.4 protocols, and enhancement suggestions are given.
Fang, Ya; Shi, Leiyu
2017-01-01
Background The digital divide persists despite broad accessibility of mobile tools. The relationship between the digital divide and health disparities reflects social status in terms of access to resources and health outcomes; however, data on this relationship are limited from developing countries such as China. Objective The aim of this study was to examine the current rates of access to mobile tools (Internet use and mobile phone ownership) among older Chinese individuals (aged ≥45 years), the predictors of access at individual and community levels, and the relationship between access to mobile tools and health outcomes. Methods We drew cross-sectional data from a national representative survey, the China Health and Retirement Longitudinal Study (CHARLS), which focused on the older population (aged ≥45 years). We used two-level mixed logistic regression models, controlling for unobserved heterogeneity at the community and individual levels for data analysis. In addition to individual-level socioeconomic status (SES), we included community-level resources such as neighborhood amenities, health care facilities, and community organizations. Health outcomes were measured by self-reported health and absence of disability based on validated scales. Results Among the 18,215 participants, 6.51% had used the Internet in the past month, and 83% owned a mobile phone. In the multivariate models, Internet use was strongly associated with SES, rural or urban residence, neighborhood amenities, community resources, and geographic region. Mobile phone ownership was strongly associated with SES and rural/urban residence but not so much with neighborhood amenities and community resources. Internet use was a significant predictor of self-reported health status, and mobile phone ownership was significantly associated with having disability even after controlling for potential confounders at the individual and community levels. Conclusions This study is one of the first to examine digital divide and its relationship with health disparities in China. The data showed a significant digital divide in China, especially in the older population. Internet access is still limited to people with higher SES; however, the mobile phone has been adopted by the general population. The digital divide is associated with not only individual SES but also community resources. Future electronic health (eHealth) programs need to consider the accessibility of mobile tools and develop culturally appropriate programs for various social groups. PMID:28893724
NASA Astrophysics Data System (ADS)
Wagh, Aditi
Two strands of work motivate the three studies in this dissertation. Evolutionary change can be viewed as a computational complex system in which a small set of rules operating at the individual level result in different population level outcomes under different conditions. Extensive research has documented students' difficulties with learning about evolutionary change (Rosengren et al., 2012), particularly in terms of levels slippage (Wilensky & Resnick, 1999). Second, though building and using computational models is becoming increasingly common in K-12 science education, we know little about how these two modalities compare. This dissertation adopts agent-based modeling as a representational system to compare these modalities in the conceptual context of micro-evolutionary processes. Drawing on interviews, Study 1 examines middle-school students' productive ways of reasoning about micro-evolutionary processes to find that the specific framing of traits plays a key role in whether slippage explanations are cued. Study 2, which was conducted in 2 schools with about 150 students, forms the crux of the dissertation. It compares learning processes and outcomes when students build their own models or explore a pre-built model. Analysis of Camtasia videos of student pairs reveals that builders' and explorers' ways of accessing rules, and sense-making of observed trends are of a different character. Builders notice rules through available blocks-based primitives, often bypassing their enactment while explorers attend to rules primarily through the enactment. Moreover, builders' sense-making of observed trends is more rule-driven while explorers' is more enactment-driven. Pre and posttests reveal that builders manifest a greater facility with accessing rules, providing explanations manifesting targeted assembly. Explorers use rules to construct explanations manifesting non-targeted assembly. Interviews reveal varying degrees of shifts away from slippage in both modalities, with students who built models not incorporating slippage explanations in responses. Study 3 compares these modalities with a control using traditional activities. Pre and posttests reveal that the two modalities manifested greater facility with accessing and assembling rules than the control. The dissertation offers implications for the design of learning environments for evolutionary change, design of the two modalities based on their strengths and weaknesses, and teacher training for the same.
Tether Elevator Crawler Systems (TECS)
NASA Technical Reports Server (NTRS)
Swenson, Frank R.
1987-01-01
One of the needs of the experimenters on the space station is access to steady and controlled-variation microgravity environments. A method of providing these environments is to place the experiment on a tether attached to the space station. This provides a high degree of isolation from structural oscillations and vibrations. Crawlers can move these experiments along the tethers to preferred locations, much like an elevator. This report describes the motion control laws developed for these crawlers and the testing of laboratory models of these tether elevator crawlers.
Kollannoor-Samuel, Grace; Vega-López, Sonia; Chhabra, Jyoti; Segura-Pérez, Sofia; Damio, Grace; Pérez-Escamilla, Rafael
2012-08-01
Racial/ethnic minorities are disproportionately affected by barriers to health care access and utilization. The primary objective was to test for an independent association between household food insecurity and health care access/utilization. In this cross-sectional survey, 211 Latinos (predominantly, Puerto-Ricans) with type 2 diabetes (T2D) were interviewed at their homes. Factor analyses identified four barriers for health care access/utilization: enabling factor, doctor access, medication access and forgetfulness. Multivariate logistic regression models examined the association between each of the barrier factors and food insecurity controlling for sociodemographic, cultural, psychosocial, and diabetes self-care variables. Higher food insecurity score was a risk factor for experiencing enabling factor (OR = 1.46; 95% CI = 1.17-1.82), medication access (OR = 1.26; 95 CI% = 1.06-1.50), and forgetfulness (OR = 1.22; 95 CI% = 1.04-1.43) barriers. Higher diabetes management self-efficacy was protective against all four barriers. Other variables associated with one or more barriers were health insurance, perceived health, depression, blood glucose, age and education. Findings suggest that addressing barriers such as food insecurity, low self-efficacy, lack of health insurance, and depression could potentially result in better health care access and utilization among low income Puerto-Ricans with T2D.
Access control for electronic patient records.
Glagola, M J
1998-01-01
The transition from hardcopy records to electronic records is in the forefront for healthcare today. For healthcare facilities, a major issue is determining who can access patients' medical information and how access to this information can be controlled. There are three components to access control: identification, authentication and authorization. Checking proof of identity is a means of authenticating someone--through a driver's license, passport or their fingerprints. Similar processes are needed in a computer environment, through the use of passwords, one-time passwords or smartcards, encryption and kerberos, and call-back procedures. New in the area of access control are biometric devices, which are hardware/software combinations that digitize a physical characteristic and compare the sample with previously stored samples. Fingerprints, voiceprints and facial features are examples. Their cost is currently prohibitive, but in time, they may become more common. Digital certificates and certification authorities are other means used to authenticate identify. When a system challenges a user's identity at log on, the user provides a certification that tells the system to go to the issuing certification authority and find proof the user's claim is valid. Low-level certifications offer little value for sensitive data, but high-level certification is now being introduced. It requires more specific, detailed information on the applicant. Authorization, the final component of access control, establishes what a specific user can and cannot access. To have effective access control, transaction logging and system monitoring are needed to ensure the various techniques are being used and performing properly.
Reports of insurance-based discrimination in health care and its association with access to care.
Han, Xinxin; Call, Kathleen Thiede; Pintor, Jessie Kemmick; Alarcon-Espinoza, Giovann; Simon, Alisha Baines
2015-07-01
We examined reports of insurance-based discrimination and its association with insurance type and access to care in the early years of the Patient Protection and Affordable Care Act. We used data from the 2013 Minnesota Health Access Survey to identify 4123 Minnesota adults aged 18 to 64 years who reported about their experiences of insurance-based discrimination. We modeled the association between discrimination and insurance type and predicted odds of having reduced access to care among those reporting discrimination, controlling for sociodemographic factors. Data were weighted to represent the state's population. Reports of insurance-based discrimination were higher among uninsured (25%) and publicly insured (21%) adults than among privately insured adults (3%), which held in the regression analysis. Those reporting discrimination had higher odds of lacking a usual source of care, lacking confidence in getting care, forgoing care because of cost, and experiencing provider-level barriers than those who did not. Further research and policy interventions are needed to address insurance-based discrimination in health care settings.
Studying "exposure" to firearms: household ownership v access
Ikeda, R; Dahlberg, L; Kresnow, M; Sacks, J; Mercy, J
2003-01-01
Background: Firearm ownership has often been used to measure access to weapons. However, persons who own a firearm may not have access to it and conversely, persons who do not own a firearm may be able to access one quickly. Objectives: To examine whether using firearm ownership is a reasonable proxy for access by describing the demographic characteristics associated with ownership and access. Methods: Data are from the 1994 Injury Control and Risk Survey, a national, random digit dial survey. Information about household firearm ownership and ready access to a loaded firearm were collected and weighted to provide national estimates. Adjusted odds ratios for three separate models were calculated using logistic regression. Results: A total of 1353 (27.9%) respondents reported both having a firearm in the household and ready access to one. An additional 313 respondents (8.1%) reported having a firearm, but were not able to access these weapons. Another 421 respondents (7.2%) did not have a firearm in or around their home, yet reported being able to retrieve and fire one within 10 minutes. Based on the logistic regression findings, the demographic characteristics of this latter group are quite different from those who report ownership. Those who do not have a firearm, but report ready access to one, are more likely to be ethnic minorities, single, and living in attached homes. Conclusions: Asking only about the presence of a firearm in a household may miss some respondents with ready access to a loaded firearm. More importantly, those who do not own a firearm, but report ready access to one, appear to be qualitatively different from those who report ownership. Caution should be exercised when using measures of ownership as a proxy for access. PMID:12642560
User-Centered Indexing for Adaptive Information Access
NASA Technical Reports Server (NTRS)
Chen, James R.; Mathe, Nathalie
1996-01-01
We are focusing on information access tasks characterized by large volume of hypermedia connected technical documents, a need for rapid and effective access to familiar information, and long-term interaction with evolving information. The problem for technical users is to build and maintain a personalized task-oriented model of the information to quickly access relevant information. We propose a solution which provides user-centered adaptive information retrieval and navigation. This solution supports users in customizing information access over time. It is complementary to information discovery methods which provide access to new information, since it lets users customize future access to previously found information. It relies on a technique, called Adaptive Relevance Network, which creates and maintains a complex indexing structure to represent personal user's information access maps organized by concepts. This technique is integrated within the Adaptive HyperMan system, which helps NASA Space Shuttle flight controllers organize and access large amount of information. It allows users to select and mark any part of a document as interesting, and to index that part with user-defined concepts. Users can then do subsequent retrieval of marked portions of documents. This functionality allows users to define and access personal collections of information, which are dynamically computed. The system also supports collaborative review by letting users share group access maps. The adaptive relevance network provides long-term adaptation based both on usage and on explicit user input. The indexing structure is dynamic and evolves over time. Leading and generalization support flexible retrieval of information under similar concepts. The network is geared towards more recent information access, and automatically manages its size in order to maintain rapid access when scaling up to large hypermedia space. We present results of simulated learning experiments.
Review of manual control methods for handheld maneuverable instruments.
Fan, Chunman; Dodou, Dimitra; Breedveld, Paul
2013-06-01
By the introduction of new technologies, surgical procedures have been varying from free access in open surgery towards limited access in minimal access surgery. Improving access to difficult-to-reach anatomic sites, e.g. in neurosurgery or percutaneous interventions, needs advanced maneuverable instrumentation. Advances in maneuverable technology require the development of dedicated methods enabling surgeons to stay in direct, manual control of these complex instruments. This article gives an overview of the state-of-the-art in the development of manual control methods for handheld maneuverable instruments. It categorizes the manual control methods in three levels: a) number of steerable segments, b) number of Degrees Of Freedom (DOF), and c) coupling between control motion of the handle and steering motion of the tip. The literature research was completed by using Web of Science, Scopus and PubMed. The study shows that in controlling single steerable segments, direct as well as indirect control methods have been developed, whereas in controlling multiple steerable segments, a gradual shift can be noticed from parallel and serial control to integrated control. The development of multi-segmented maneuverable instruments is still at an early stage, and an intuitive and effective method to control them has to become a primary focus in the domain of minimal access surgery.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-16
... the firm controls access to market data and not for external interrogation devices or internal interrogation devices for which a vendor (and not the firm) controls access to market data. This program better... that its employees use and in respect of which the firm controls access to market data. The...
On the Design of a Comprehensive Authorisation Framework for Service Oriented Architecture (SOA)
2013-07-01
Authentication Server AZM Authorisation Manager AZS Authorisation Server BP Business Process BPAA Business Process Authorisation Architecture BPAD Business...Internet Protocol Security JAAS Java Authentication and Authorisation Service MAC Mandatory Access Control RBAC Role Based Access Control RCA Regional...the authentication process, make authorisation decisions using application specific access control functions that results in the practice of
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-27
... anonymous access system, and EPA will not know your identity or contact information unless you provide it in... control measures. Section 110(a)(2)(B): Ambient air quality monitoring/data system. Section 110(a)(2)(C... significant deterioration (PSD) and visibility protection. Section 110(a)(2)(K): Air quality modeling and...
Adaptive, Tactical Mesh Networking: Control Base MANET Model
2010-09-01
pp. 316–320 Available: IEEE Xplore , http://ieeexplore.ieee.org [Accessed: June 9, 2010]. [5] N. Sidiropoulos, “Multiuser Transmit Beamforming...Mobile Mesh Segments of TNT Testbed .......... 11 Figure 5. Infrastructure and Ad Hoc Mode of IEEE 802.11................................ 13 Figure...6. The Power Spectral Density of OFDM................................................ 14 Figure 7. A Typical IEEE 802.16 Network
Toward a Model for the Conceptual Understanding of Personal Learning Environments: A Case Study
ERIC Educational Resources Information Center
Ivanova, Malinka; Chatti, Mohamed Amine
2011-01-01
The development of Personal Learning Environments (PLEs) is in the scope of research groups and educators aiming to propose suitable mechanisms for the organization of self-controlled and self-directed learning, providing students with tools and services for access to content and human intelligence inside and outside the educational institutions.…
Bounded and Unbounded Knowledge: Teaching and Learning in a Web 2 World
ERIC Educational Resources Information Center
Nagy, Judy; Bigum, Chris
2007-01-01
In the recent past, the proliferation of digitally available content heralded the beginning of serious problems for the business models of publishers. The ease with which content can be accessed, copied and distributed disrupts the control of those whose role has been to manage and profit from the intellectual property rights of content producers.…
Securing Secrets and Managing Trust in Modern Computing Applications
ERIC Educational Resources Information Center
Sayler, Andy
2016-01-01
The amount of digital data generated and stored by users increases every day. In order to protect this data, modern computing systems employ numerous cryptographic and access control solutions. Almost all of such solutions, however, require the keeping of certain secrets as the basis of their security models. How best to securely store and control…
2017-03-03
When a neighbor receives one of these packets, it waits until the end of the transmit time and then responds with its own hello packet, containing its...and 3 respond with their own hello packet. Location Tracking Another important feature is location tracking. Due to node mobility, it is vital that
Simulation and Modeling of a New Medium Access Control Scheme for Multi-Beam Directional Networking
2017-03-03
of these packets, it waits until the end of the transmit time and then responds with its own hello packet, containing its own location, as well as...own hello packet. Location Tracking Another important feature is location tracking. Due to node mobility, it is vital that each node tracks the
Haynes-Maslow, Lindsey; Leone, Lucia A
2017-08-09
Inequitable access to healthy food may contribute to health disparities. This study examines the relationship between the prevalence of adult diabetes and food access in the U.S. by county economic/racial composition. An ecological study from 2012 was used to estimate the relationship between diabetes and retail food outlet access. County diabetes prevalence was measured based on individual responses to the Behavioral Risk Factor Surveillance Survey question, "Have you ever been told by a doctor that you have diabetes?" If the answer was "yes" individuals were classified as having diabetes. Retail food outlets included grocery stores, supercenters, farmer's markets, full-service restaurants, fast food restaurants and convenience stores. Counties were categorized as "high-poverty" or "low-poverty". Counties were categorized as low (< 4.6%), medium (4.6%-31.0%), and high (> 31.0%) percent minority residents. Multiple linear regression models estimated the association between retail food outlets and diabetes, controlling for confounders, and testing for interactions between retail food outlets and county racial composition. Regression models were conditioned on county economic composition. Data were analyzed in 2016. Density of retail foods outlets varied greatly by county economic and racial composition; counties with medium-minority populations had the least access to grocery stores and the highest access to fast food restaurants and convenience stores. Low poverty/low-minority population counties had the greatest access to farmer's markets and grocery stores. For low poverty/low-minority counties, grocery stores were associated with decreased of diabetes prevalence. Supercenters were associated with an increase in diabetes prevalence for high-poverty/low-minority counties. Only low poverty/medium-minority counties had a statistically significant relationship between farmer's markets and diabetes prevalence. Fast food restaurants were found to be positively associated with diabetes prevalence in all counties except high poverty/medium-minority. However, only low poverty/low-minority counties had a statistically significant relationship. Across all models, access to full service restaurants were significantly associated with lower prevalence of diabetes. Generally, access to convenience stores were associated with increased diabetes prevalence, except for high poverty/low-minority counties. The food environment is more strongly associated with diabetes prevalence for wealthier counties with a lower proportion of minority residents. This is important given efforts to increase food access in vulnerable communities. Availability of healthier food may not be enough to change health outcomes.
Toward Privacy-preserving Content Access Control for Information Centric Networking
2014-03-01
REPORT Toward Privacy-preserving Content Access Control for Information Centric Networking 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: Information...regardless the security mechanisms provided by different content hosting servers. However, using ABE has a drawback that the enforced content access...Encryption (ABE) is a flexible approach to enforce the content access policies regardless the security mechanisms provided by different content hosting
Approach to spatial information security based on digital certificate
NASA Astrophysics Data System (ADS)
Cong, Shengri; Zhang, Kai; Chen, Baowen
2005-11-01
With the development of the online applications of geographic information systems (GIS) and the spatial information services, the spatial information security becomes more important. This work introduced digital certificates and authorization schemes into GIS to protect the crucial spatial information combining the techniques of the role-based access control (RBAC), the public key infrastructure (PKI) and the privilege management infrastructure (PMI). We investigated the spatial information granularity suited for sensitivity marking and digital certificate model that fits the need of GIS security based on the semantics analysis of spatial information. It implements a secure, flexible, fine-grained data access based on public technologies in GIS in the world.
Routes to DNA accessibility: alternative pathways for nucleosome unwinding.
Schlingman, Daniel J; Mack, Andrew H; Kamenetska, Masha; Mochrie, Simon G J; Regan, Lynne
2014-07-15
The dynamic packaging of DNA into chromatin is a key determinant of eukaryotic gene regulation and epigenetic inheritance. Nucleosomes are the basic unit of chromatin, and therefore the accessible states of the nucleosome must be the starting point for mechanistic models regarding these essential processes. Although the existence of different unwound nucleosome states has been hypothesized, there have been few studies of these states. The consequences of multiple states are far reaching. These states will behave differently in all aspects, including their interactions with chromatin remodelers, histone variant exchange, and kinetic properties. Here, we demonstrate the existence of two distinct states of the unwound nucleosome, which are accessible at physiological forces and ionic strengths. Using optical tweezers, we measure the rates of unwinding and rewinding for these two states and show that the rewinding rates from each state are different. In addition, we show that the probability of unwinding into each state is dependent on the applied force and ionic strength. Our results demonstrate not only that multiple unwound states exist but that their accessibility can be differentially perturbed, suggesting possible roles for these states in gene regulation. For example, different histone variants or modifications may facilitate or suppress access to DNA by promoting unwinding into one state or the other. We anticipate that the two unwound states reported here will be the basis for future models of eukaryotic transcriptional control. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.
Fone, David L; Christie, Stephen; Lester, Nathan
2006-04-13
Assessment of the spatial accessibility of hospital accident and emergency departments as perceived by local residents has not previously been investigated. Perceived accessibility may affect where, when, and whether potential patients attend for treatment. Using data on 11,853 respondents to a population survey in Caerphilly county borough, Wales, UK, we present an analysis comparing the accessibility of accident and emergency departments as reported by local residents and drive-time to the nearest accident and emergency department modelled using a geographical information system (GIS). Median drive-times were significantly shorter in the lowest perceived access category and longer in the best perceived access category (p < 0.001). The perceived access and GIS modelled drive-time variables were positively correlated (Spearman's rank correlation coefficient, r = 0.38, p < 0.01). The strongest correlation was found for respondents living in areas in which nearly all households had a car or van (r = 0.47, p < 0.01). Correlations were stronger among respondents reporting good access to public transport and among those reporting a recent accident and emergency attendance for injury treatment compared to other respondents. Correlation coefficients did not vary substantially by levels of household income. Drive-time, road distance and straight-line distance were highly inter-correlated and substituting road distance or straight-line distance as the GIS modelled spatial accessibility measure only marginally decreased the magnitude of the correlations between perceived and GIS modelled access. This study provides evidence that the accessibility of hospital-based health care services as perceived by local residents is related to measures of spatial accessibility modelled using GIS. For studies that aim to model geographical separation in a way that correlates well with the perception of local residents, there may be minimal advantage in using sophisticated measures. Straight-line distance, which can be calculated without GIS, may be as good as GIS-modelled drive-time or distance for this purpose. These findings will be of importance to health policy makers and local planners who seek to obtain local information on access to services through focussed assessments of residents' concerns over accessibility and GIS modelling.
Accession Gaming Model (AGAM).
1980-08-01
k D-A009 160 NAVY PERSONNEL RESEARCH AND DEVELOPMENT CENTER SAN 0--ETC F/6 5/9 ACCESSION GAMING MODEL (AGAM).(U) UA 80 A WHISNAN, Y YEN, M...RECIPIENT’SCATALOG NUMBER NPRDC-TR_8 - vA - c I _ _ _ _ _ _ _ *:TITLE (and Suabitle) S. TYPE OF REPORT& PERIOD COVERED /ACCESSION GAMING MODEL (AG AM) ’C Final FY79 S...billet, trained personnel, and untrained personnel requirements, and the development of an Accession Gaming Model (AGAM), an optimization model that
Breaking and Fixing Origin-Based Access Control in Hybrid Web/Mobile Application Frameworks
Georgiev, Martin; Jana, Suman; Shmatikov, Vitaly
2014-01-01
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 and explain why they are ineffectual. We then present NoFrak, a capability-based defense against fracking attacks. NoFrak is platform-independent, compatible with any framework and embedded browser, requires no changes to the code of the existing hybrid apps, and does not break their advertising-supported business model. PMID:25485311
Ruiz-Rodriguez, Ernesto; Asfour, Ahmed; Lolay, Georges; Ziada, Khaled M.; Abdel-Latif, Ahmed K.
2016-01-01
Objectives Radial artery access (RA) for left heart catheterization and percutaneous coronary interventions (PCIs) has been demonstrated to be safe and effective. Despite consistent data showing less bleeding complications compared with femoral artery access (FA), it continues to be underused in the United States, particularly in patients with acute coronary syndrome (ACS) in whom aggressive anticoagulation and platelet inhibition regimens are needed. This systematic review and meta-analysis aims to compare major cardiovascular outcomes and safety endpoints in patients with ACS managed with PCI using radial versus femoral access. Methods Randomized controlled trials and cohort studies comparing RA versus FA in patients with ACS were analyzed. Our primary outcomes were mortality, major adverse cardiac event, major bleeding, and access-related complications. A fixed-effects model was used for the primary analyses. Results Fifteen randomized controlled trials and 17 cohort studies involving 44,854 patients with ACS were identified. Compared with FA, RA was associated with a reduction in major bleeding (odds ratio [OR] 0.45, 95% confidence interval [CI] 0.33–0.61; P < 0.001), access-related complications (OR 0.27, 95% CI 0.18–0.39; P < 0.001), mortality (OR 0.64, 95% CI 0.54–0.75; P < 0.001), and major adverse cardiac event (OR 0.70, 95% CI 0.57–0.85; P < 0.001). These significant reductions were consistent across different study designs and clinical presentations. Conclusions Based on this large meta-analysis, RA for primary PCI in the setting of ACS is associated with reduction in cardiac and safety endpoints when compared with FA in both urgent and elective procedures. This should encourage a wider adoption of this technique among centers and interventional cardiologists. PMID:26741877
The control of purity and stoichiometry of compound semiconductors by high vapor pressure transport
NASA Technical Reports Server (NTRS)
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).
Patient-reported access to primary care in Ontario: effect of organizational characteristics.
Muggah, Elizabeth; Hogg, William; Dahrouge, Simone; Russell, Grant; Kristjansson, Elizabeth; Muldoon, Laura; Devlin, Rose Anne
2014-01-01
To describe patient-reported access to primary health care across 4 organizational models of primary care in Ontario, and to explore how access is associated with patient, provider, and practice characteristics. Cross-sectional survey. One hundred thirty-seven randomly selected primary care practices in Ontario using 1 of 4 delivery models (fee for service, established capitation, reformed capitation, and community health centres). Patients included were at least 18 years of age, were not severely ill or cognitively impaired, were not known to the survey administrator, had consenting providers at 1 of the participating primary care practices, and were able to communicate in English or French either directly or through a translator. Patient-reported access was measured by a 4-item scale derived from the previously validated adult version of the Primary Care Assessment Tool. Questions were asked about physician availability during and outside of regular office hours and access to health information via telephone. Responses to the scale were normalized, with higher scores reflecting greater patient-reported access. Linear regressions were used to identify characteristics independently associated with access to care. Established capitation model practices had the highest patient-reported access, although the difference in scores between models was small. Our multilevel regression model identified several patient factors that were significantly (P = .05) associated with higher patient-reported access, including older age, female sex, good-to-excellent self-reported health, less mental health disability, and not working. Provider experience (measured as years since graduation) was the only provider or practice characteristic independently associated with improved patient-reported access. This study adds to what is known about access to primary care. The study found that established capitation models outperformed all the other organizational models, including reformed capitation models, independent of provider and practice variables save provider experience. This suggests that the capitation models might provide better access to care and that it might take time to realize the benefits of organizational reforms.
Wimmer, Mark H; Heffner, Kenneth; Smithers, Michael; Culley, Richard; Coyner, Jennifer; Loughren, Michael; Johnson, Don
2016-01-01
The American Heart Association (AHA) recommends intravenous (IV) or intraosseous (IO) vasopressin in Advanced Cardiac Life Support (ACLS). Obtaining IV access in hypovolemic cardiac arrest patients can be difficult, and IO access is often obtained in these life threatening situations. No studies have been conducted to determine the effects of humeral IO (HIO) access with vasopressin in the return of spontaneous circulation (ROSC). Our study compared the kinetics of vasopressin and ROSC with HIO with IV access in the hypovolemic swine model. Twenty-two Yorkshire swine were divided into three groups: HIO (n = 7), IV (n = 8), and a control group (n = 7). The IV and HIO group received vasopressin and cardiopulmonary resuscitation (CPR), while the control group received only CPR. All subjects were exsanguinated 31 percent of their blood volume, placed in cardiac arrest, and resuscitated per ACLS. Subjects that achieved ROSC were then monitored for 20 minutes. Blood samples (10 mL) collected at 0.5, 1, 1.5, 2, 2.5, 3, and 4 minutes after vasopressin injection and analyzed for maximum concentration (Cmax) and time to maximum concentration (Tmax). Data were analyzed using a multivariate analysis of variance (MANOVA) and a Fisher's Exact Test. ROSC was achieved in every subject that received vasopressin via the HIO route. Data analysis using a MANOVA pairwise comparison revealed no difference between mean Cmax (p = 0.601) and Tmax (p = 0.771) of vasopressin administered IV versus HIO routes. Analysis of the mean serum concentrations at time intervals using a repeated measures analysis of variance found no difference (p > 0.05). A Fisher's Exact Test revealed no difference in rate of ROSC between HIO and IV groups (p > 0.05). Odds ratio determined that there was a 33 times higher chance of survival among HIO subjects versus control (CPR and Defibrillation; p = 0.03) and no difference in the survivability of the HIO or IV groups (p = 0.52). The data from this study strongly suggest that there is no significant difference in ROSC, time to ROSC, hemodynamics, or pharmacokinetics between HIO vasopressin and IV vasopressin. This research reinforces current AHA guidelines recommending the use of HIO route early over delaying care awaiting IV access.
Nøst, Torunn Hatlen; Steinsbekk, Aslak; Bratås, Ola; Grønning, Kjersti
2016-07-18
People struggling with chronic pain may benefit from different types of non-pharmacological interventions such as self-management courses. Self-management courses aim to increase participants' skills and knowledge in managing chronic conditions. Community health-care services in Norway have increasingly established Healthy Life Centres (HLCs) to offer easily accessible interventions to people in need of support to better handle a life with chronic illness. The aim of this trial is to investigate the expectations, effect and experience of an easily accessible, group-based self-management course delivered at a HLC for people with chronic pain. This is an open pragmatic two-armed randomised controlled trial with an embedded qualitative study. The intervention is a self-management course comprising education, discussions, exchange of experiences between the participants, and physical movement exercises. The control group is offered a drop-in outdoor physical activity. The intervention period is 6 weeks. The primary outcome is patient activation measured by the patient activation measure (PAM). The secondary outcomes include measures of self-efficacy, pain and quality of life. Data will be collected at baseline, and after 3, 6 and 12 months. Using a mixed linear model, the number needed in each arm to achieve a power of 80 % becomes 55. To allow for dropout, the aim is to include 120 participants. Analysis will be done using mixed linear models. In the embedded qualitative study, we will perform semi-structured face-to-face interviews with a sample from both trial arms before randomisation and after 3 and 12 months. The topics elaborated will be motivation for participation and experiences with the activity related to possible changes in managing and coping with chronic pain. There is need for more knowledge on interventions delivering self-care support in an easily accessible way that aim to reach those in need of this kind of health service. This trial will produce important knowledge on the effect and the experiences of participants in such an easily accessible self-management course delivered in Norwegian public primary care. ClinicalTrials.gov: NCT02531282 . Registered on 21 August 2015.
Ke, Chih-Kun; Lin, Zheng-Hua
2015-09-01
The progress of information and communication technologies (ICT) has promoted the development of healthcare which has enabled the exchange of resources and services between organizations. Organizations want to integrate mobile devices into their hospital information systems (HIS) due to the convenience to employees who are then able to perform specific healthcare processes from any location. The collection and merage of healthcare data from discrete mobile devices are worth exploring possible ways for further use, especially in remote districts without public data network (PDN) to connect the HIS. In this study, we propose an optimal mobile service which automatically synchronizes the telecare file resources among discrete mobile devices. The proposed service enforces some technical methods. The role-based access control model defines the telecare file resources accessing mechanism; the symmetric data encryption method protects telecare file resources transmitted over a mobile peer-to-peer network. The multi-criteria decision analysis method, ELECTRE (Elimination Et Choice Translating Reality), evaluates multiple criteria of the candidates' mobile devices to determine a ranking order. This optimizes the synchronization of telecare file resources among discrete mobile devices. A prototype system is implemented to examine the proposed mobile service. The results of the experiment show that the proposed mobile service can automatically and effectively synchronize telecare file resources among discrete mobile devices. The contribution of this experiment is to provide an optimal mobile service that enhances the security of telecare file resource synchronization and strengthens an organization's mobility.
Searchable attribute-based encryption scheme with attribute revocation in cloud storage.
Wang, Shangping; Zhao, Duqiao; Zhang, Yaling
2017-01-01
Attribute based encryption (ABE) is a good way to achieve flexible and secure access control to data, and attribute revocation is the extension of the attribute-based encryption, and the keyword search is an indispensable part for cloud storage. The combination of both has an important application in the cloud storage. In this paper, we construct a searchable attribute-based encryption scheme with attribute revocation in cloud storage, the keyword search in our scheme is attribute based with access control, when the search succeeds, the cloud server returns the corresponding cipher text to user and the user can decrypt the cipher text definitely. Besides, our scheme supports multiple keywords search, which makes the scheme more practical. Under the assumption of decisional bilinear Diffie-Hellman exponent (q-BDHE) and decisional Diffie-Hellman (DDH) in the selective security model, we prove that our scheme is secure.
Two Mechanisms to Avoid Control Conflicts Resulting from Uncoordinated Intent
NASA Technical Reports Server (NTRS)
Mishkin, Andrew H.; Dvorak, Daniel L.; Wagner, David A.; Bennett, Matthew B.
2013-01-01
This software implements a real-time access control protocol that is intended to make all connected users aware of the presence of other connected users, and which of them is currently in control of the system. Here, "in control" means that a single user is authorized and enabled to issue instructions to the system. The software The software also implements a goal scheduling mechanism that can detect situations where plans for the operation of a target system proposed by different users overlap and interact in conflicting ways. In such situations, the system can either simply report the conflict (rejecting one goal or the entire plan), or reschedule the goals in a way that does not conflict. The access control mechanism (and associated control protocol) is unique. Other access control mechanisms are generally intended to authenticate users, or exclude unauthorized access. This software does neither, and would likely depend on having some other mechanism to support those requirements.
How well are malaria maps used to design and finance malaria control in Africa?
Omumbo, Judy A; Noor, Abdisalan M; Fall, Ibrahima S; Snow, Robert W
2013-01-01
Rational decision making on malaria control depends on an understanding of the epidemiological risks and control measures. National Malaria Control Programmes across Africa have access to a range of state-of-the-art malaria risk mapping products that might serve their decision-making needs. The use of cartography in planning malaria control has never been methodically reviewed. An audit of the risk maps used by NMCPs in 47 malaria endemic countries in Africa was undertaken by examining the most recent national malaria strategies, monitoring and evaluation plans, malaria programme reviews and applications submitted to the Global Fund. The types of maps presented and how they have been used to define priorities for investment and control was investigated. 91% of endemic countries in Africa have defined malaria risk at sub-national levels using at least one risk map. The range of risk maps varies from maps based on suitability of climate for transmission; predicted malaria seasons and temperature/altitude limitations, to representations of clinical data and modelled parasite prevalence. The choice of maps is influenced by the source of the information. Maps developed using national data through in-country research partnerships have greater utility than more readily accessible web-based options developed without inputs from national control programmes. Although almost all countries have stratification maps, only a few use them to guide decisions on the selection of interventions allocation of resources for malaria control. The way information on the epidemiology of malaria is presented and used needs to be addressed to ensure evidence-based added value in planning control. The science on modelled impact of interventions must be integrated into new mapping products to allow a translation of risk into rational decision making for malaria control. As overseas and domestic funding diminishes, strategic planning will be necessary to guide appropriate financing for malaria control.
Buhi, Eric R.; Baldwin, Julie; Chen, Henian; Johnson, Ayesha; Lynn, Vickie; Glueckauf, Robert
2014-01-01
Abstract Introduction: Expanded access to efficacious interventions is needed for women living with human immunodeficiency virus (WLH) in the United States. Availability of “prevention with (human immunodeficiency virus [HIV)] positives” interventions in rural/remote and low HIV prevalence areas remains limited, leaving WLH in these communities few options for receiving effective behavioral interventions such as Healthy Relationships (HR). Offering such programs via videoconferencing groups (VGs) may expand access. This analysis tests the effectiveness of HR-VG (versus wait-list control) for reducing sexual risk behavior among WLH and explores intervention satisfaction. Subjects and Methods: In this randomized controlled trial unprotected vaginal/anal sex occasions over the prior 3 months reported at the 6-month follow-up were compared across randomization groups through zero-inflated Poisson regression modeling, controlling for unprotected sex at baseline. Seventy-one WLH were randomized and completed the baseline assessment (n=36 intervention and n=35 control); 59 (83% in each group) had follow-up data. Results: Among those who engaged in unprotected sex at 6-month follow-up, intervention participants had approximately seven fewer unprotected occasions than control participants (95% confidence interval 5.43–7.43). Intervention participants reported high levels of satisfaction with HR-VG; 84% reported being “very satisfied” overall. Conclusions: This study found promising evidence for effective dissemination of HIV risk reduction interventions via VGs. Important next steps will be to determine whether VGs are effective with other subpopulations of people living with HIV (i.e., men and non-English speakers) and to assess cost-effectiveness. Possibilities for using VGs to expand access to other psychosocial and behavioral interventions and reduce stigma are discussed. PMID:24237482
2012-01-01
Background In the United Kingdom and worldwide, there is significant policy interest in improving the quality of care for patients with mental health disorders and distress. Improving quality of care means addressing not only the effectiveness of interventions but also the issue of limited access to care. Research to date into improving access to mental health care has not been strongly rooted within a conceptual model, nor has it systematically identified the different elements of the patient journey from identification of illness to receipt of care. This paper set out to review core concepts underlying patient access to mental health care, synthesise these to develop a conceptual model of access, and consider the implications of the model for the development and evaluation of interventions for groups with poor access to mental health care such as older people and ethnic minorities. Methods Narrative review of the literature to identify concepts underlying patient access to mental health care, and synthesis into a conceptual model to support the delivery and evaluation of complex interventions to improve access to mental health care. Results The narrative review adopted a process model of access to care, incorporating interventions at three levels. The levels comprise (a) community engagement (b) addressing the quality of interactions in primary care and (c) the development and delivery of tailored psychosocial interventions. Conclusions The model we propose can form the basis for the development and evaluation of complex interventions in access to mental health care. We highlight the key methodological challenges in evaluating the overall impact of access interventions, and assessing the relative contribution of the different elements of the model. PMID:22889290
Tam, Jamie; Levy, David T; Jeon, Jihyoun; Clarke, John; Gilkeson, Scott; Hall, Tim; Feuer, Eric J; Holford, Theodore R; Meza, Rafael
2018-03-23
Smoking remains the leading cause of preventable death in the USA but can be reduced through policy interventions. Computational models of smoking can provide estimates of the projected impact of tobacco control policies and can be used to inform public health decision making. We outline a protocol for simulating the effects of tobacco policies on population health outcomes. We extend the Smoking History Generator (SHG), a microsimulation model based on data from the National Health Interview Surveys, to evaluate the effects of tobacco control policies on projections of smoking prevalence and mortality in the USA. The SHG simulates individual life trajectories including smoking initiation, cessation and mortality. We illustrate the application of the SHG policy module for four types of tobacco control policies at the national and state levels: smoke-free air laws, cigarette taxes, increasing tobacco control programme expenditures and raising the minimum age of legal access to tobacco. Smoking initiation and cessation rates are modified by age, birth cohort, gender and years since policy implementation. Initiation and cessation rate modifiers are adjusted for differences across age groups and the level of existing policy coverage. Smoking prevalence, the number of population deaths avoided, and life-years gained are calculated for each policy scenario at the national and state levels. The model only considers direct individual benefits through reduced smoking and does not consider benefits through reduced exposure to secondhand smoke. A web-based interface is being developed to integrate the results of the simulations into a format that allows the user to explore the projected effects of tobacco control policies in the USA. Usability testing is being conducted in which experts provide feedback on the interface. Development of this tool is under way, and a publicly accessible website is available at http://www.tobaccopolicyeffects.org. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Levy, David T; Jeon, Jihyoun; Clarke, John; Gilkeson, Scott; Hall, Tim; Holford, Theodore R; Meza, Rafael
2018-01-01
Introduction Smoking remains the leading cause of preventable death in the USA but can be reduced through policy interventions. Computational models of smoking can provide estimates of the projected impact of tobacco control policies and can be used to inform public health decision making. We outline a protocol for simulating the effects of tobacco policies on population health outcomes. Methods and analysis We extend the Smoking History Generator (SHG), a microsimulation model based on data from the National Health Interview Surveys, to evaluate the effects of tobacco control policies on projections of smoking prevalence and mortality in the USA. The SHG simulates individual life trajectories including smoking initiation, cessation and mortality. We illustrate the application of the SHG policy module for four types of tobacco control policies at the national and state levels: smoke-free air laws, cigarette taxes, increasing tobacco control programme expenditures and raising the minimum age of legal access to tobacco. Smoking initiation and cessation rates are modified by age, birth cohort, gender and years since policy implementation. Initiation and cessation rate modifiers are adjusted for differences across age groups and the level of existing policy coverage. Smoking prevalence, the number of population deaths avoided, and life-years gained are calculated for each policy scenario at the national and state levels. The model only considers direct individual benefits through reduced smoking and does not consider benefits through reduced exposure to secondhand smoke. Ethics and dissemination A web-based interface is being developed to integrate the results of the simulations into a format that allows the user to explore the projected effects of tobacco control policies in the USA. Usability testing is being conducted in which experts provide feedback on the interface. Development of this tool is under way, and a publicly accessible website is available at http://www.tobaccopolicyeffects.org. PMID:29574440
Hassan, Sehar-un-Nisa; Siddiqui, Salma; Mahmood, Ayeshah
2015-01-01
Background and Objective: Fertility control preferences and maternal healthcare have recently become a major concern for developing nations with evidence suggesting that low fertility control rates and poor maternal healthcare are among major obstructions in ensuring health and social status for women. Our objective was toanalyze the factors that influence women’s autonomy, access to maternal healthcare, and fertility control preferences in Pakistan. Methods: Data consisted of 11,761 ever-married women of ages 15-49 years from PDHS, 2012-13. Variables included socio-demographics, women’s autonomy, fertility control preferences and access to maternal healthcare. Results: Findings from multivariate analysis showed that women’s younger age, having less than three number of children and independent or joint decision-making (indicators of high autonomy) remained the most significant predictors for access to better quality maternal healthcare and better fertility control preferences when other variables were controlled. Conclusion: Women’s access to good quality maternal health care and fertility control preferences are directly and indirectly influenced by their demographic characteristics and decision-making patterns in domestic affairs. PMID:26870096
Designing and Evaluating Interventions to Eliminate Racial and Ethnic Disparities in Health Care
Cooper, Lisa A; Hill, Martha N; Powe, Neil R
2002-01-01
A large number of factors contribute to racial and ethnic disparities in health status. Health care professionals, researchers, and policymakers have believed for some time that access to care is the centerpiece in the elimination of these health disparities. The Institute of Medicine's (IOM) model of access to health services includes personal, financial, and structural barriers, health service utilization, and mediators of care. This model can be used to describe the interactions among these factors and their impact on health outcomes and equity of services among racial and ethnic groups. We present a modified version of the IOM model that incorporates the features of other access models and highlights barriers and mediators that are relevant for interventions designed to eliminate disparities in U.S. health care. We also suggest that interventions to eliminate disparities and achieve equity in health care services be considered within the broader context of improving quality of care. Some health service intervention studies have shown improvements in the health of disadvantaged groups. If properly designed and implemented, these interventions could be used to reduce health disparities. Successful features of interventions include the use of multifaceted, intense approaches, culturally and linguistically appropriate methods, improved access to care, tailoring, the establishment of partnerships with stakeholders, and community involvement. However, in order to be effective in reducing disparities in health care and health status, important limitations of previous studies need to be addressed, including the lack of control groups, nonrandom assignment of subjects to experimental interventions, and use of health outcome measures that are not validated. Interventions might be improved by targeting high-risk populations, focusing on the most important contributing factors, including measures of appropriateness and quality of care and health outcomes, and prioritizing dissemination efforts. PMID:12133164
1993-04-01
for using out-of- network benefits . * A gatekeeper physician controls access to the network and is paid on a capitated or discounted fee- for-service...Model ...................... 84 Figure 10. Organization Under Managed Care/HMO Concept ............... 94 APPENDIX 1. Benefit Under CCP 2. Group Model...increases, yet our health indicators have not improved (e.g., infant mortality, adult mortality, morbidity, or life expectancy). The aging population, the
THE ART OF DATA MINING THE MINEFIELDS OF TOXICITY ...
Toxicity databases have a special role in predictive toxicology, providing ready access to historical information throughout the workflow of discovery, development, and product safety processes in drug development as well as in review by regulatory agencies. To provide accurate information within a hypothesesbuilding environment, the content of the databases needs to be rigorously modeled using standards and controlled vocabulary. The utilitarian purposes of databases widely vary, ranging from a source for (Q)SAR datasets for modelers to a basis for
Assessing access to surgical care in Nepal via a cross-sectional, countrywide survey.
Boeck, Marissa A; Nagarajan, Neeraja; Gupta, Shailvi; Varadaraj, Varshini; Groen, Reinou S; Shrestha, Sunil; Gurung, Susant; Kushner, Adam L; Nwomeh, Benedict; Swaroop, Mamta
2016-08-01
Adequate surgical care is lacking in many low- and middle-income countries because of diverse barriers preventing patients from reaching providers. We sought to assess perceived difficulties to accessing surgical care in Nepal using the Surgeons OverSeas Assessment of Surgical Need tool. Fifteen of 75 Nepali districts were selected proportionate to the population, with 1,350 households surveyed. Household heads answered questions regarding access to health facilities, and 2 household members were interviewed for medical history. Continuous and categorical variables were analyzed via Wilcoxon rank sum test and Pearson χ(2) test. Multivariable logistic regressions for independent predictors of care access were performed controlling for age, sex, location, and literacy. Of respondents with a surgical condition (n = 1,342), 650 (48.4%) accessed care and 237 (17.7%) did not. Unadjusted analyses showed greater median travel times to all facilities (P < .001) and median transport costs to secondary and tertiary centers (P < .001) for those who did not access care versus those who did. Literate respondents were more likely to access care across all facilities and access variables in adjusted models (odds ratio 1.66-1.80, P < .01). Those without transport money were less likely to access care at any facility in all analyses (P < .01). The data project that at least 2.4 million individuals lack access to needed surgical care in Nepal during their lifetimes, with those not accessing health facilities having lower literacy rates and fewer transport resources. Promoting education, outreach programs, and transportation access could lessen barriers but will require further exploration. Copyright © 2016 Elsevier Inc. All rights reserved.
Johnson-Ulrich, Lily; Johnson-Ulrich, Zoe; Holekamp, Kay
2018-05-01
Innovation is widely linked to cognitive ability, brain size, and adaptation to novel conditions. However, successful innovation appears to be influenced by both cognitive factors, such as inhibitory control, and non-cognitive behavioral traits. We used a multi-access box (MAB) paradigm to measure repeated innovation, the number of unique innovations learned across trials, by 10 captive spotted hyenas (Crocuta crocuta). Spotted hyenas are highly innovative in captivity and also display striking variation in behavioral traits, making them good model organisms for examining the relationship between innovation and other behavioral traits. We measured persistence, motor diversity, motivation, activity, efficiency, inhibitory control, and neophobia demonstrated by hyenas while interacting with the MAB. We also independently assessed inhibitory control with a detour cylinder task. Most hyenas were able to solve the MAB at least once, but only four hyenas satisfied learning criteria for all four possible solutions. Interestingly, neither measure of inhibitory control predicted repeated innovation. Instead, repeated innovation was predicted by a proactive syndrome of behavioral traits that included high persistence, high motor diversity, high activity and low neophobia. Our results suggest that this proactive behavioral syndrome may be more important than inhibitory control for successful innovation with the MAB by members of this species.
Upgrade to the control system of the reflectometry diagnostic of ASDEX upgrade
NASA Astrophysics Data System (ADS)
Graça, S.; Santos, J.; Manso, M. E.
2004-10-01
The broadband frequency modulation-continuous wave microwave/millimeter wave reflectometer of ASDEX upgrade tokamak (Institut für Plasma Physik (IPP), Garching, Germany) developed by Centro de Fusão Nuclear (Lisboa, Portugal) with the collaboration of IPP, is a complex system with 13 channels (O and X modes) and two types of operation modes (swept and fixed frequency). The control system that ensures remote operation of the diagnostic incorporates VME and CAMAC bus based acquisition/timing systems. Microprocessor input/output boards are used to control and monitor the microwave circuitry and associated electronic devices. The implementation of the control system is based on an object-oriented client/server model: a centralized server manages the hardware and receives input from remote clients. Communication is handled through transmission control protocol/internet protocol sockets. Here we describe recent upgrades of the control system aiming to: (i) accommodate new channels; (ii) adapt to the heterogeneity of computing platforms and operating systems; and (iii) overcome remote access restrictions. Platform and operating system independence was achieved by redesigning the graphical user interface in JAVA. As secure shell is the standard remote access protocol adopted in major fusion laboratories, secure shell tunneling was implemented to allow remote operation of the diagnostic through the existing firewalls.
Comparing the role of fuel breaks across southern California national forests
Syphard, Alexandra D.; Keeley, Jon E.; Brennan, Teresa J.
2011-01-01
Fuel treatment of wildland vegetation is the primary approach advocated for mitigating fire risk at the wildland-urban interface (WUI), but little systematic research has been conducted to understand what role fuel treatments play in controlling large fires, which factors influence this role, or how the role of fuel treatments may vary over space and time. We assembled a spatial database of fuel breaks and fires from the last 30 years in four southern California national forests to better understand which factors are consistently important for fuel breaks in the control of large fires. We also explored which landscape features influence where fires and fuel breaks are most likely to intersect. The relative importance of significant factors explaining fuel break outcome and number of fire and fuel break intersections varied among the forests, which reflects high levels of regional landscape diversity. Nevertheless, several factors were consistently important across all the forests. In general, fuel breaks played an important role in controlling large fires only when they facilitated fire management, primarily by providing access for firefighting activities. Fire weather and fuel break maintenance were also consistently important. Models and maps predicting where fuel breaks and fires are most likely to intersect performed well in the regions where the models were developed, but these models did not extend well to other regions, reflecting how the environmental controls of fire regimes vary even within a single ecoregion. Nevertheless, similar mapping methods could be adopted in different landscapes to help with strategic location of fuel breaks. Strategic location of fuel breaks should also account for access points near communities, where fire protection is most important.
[Access control management in electronic health records: a systematic literature review].
Carrión Señor, Inmaculada; Fernández Alemán, José Luis; Toval, Ambrosio
2012-01-01
This study presents the results of a systematic literature review of aspects related to access control in electronic health records systems, wireless security and privacy and security training for users. Information sources consisted of original articles found in Medline, ACM Digital Library, Wiley InterScience, IEEE Digital Library, Science@Direct, MetaPress, ERIC, CINAHL and Trip Database, published between January 2006 and January 2011. A total of 1,208 articles were extracted using a predefined search string and were reviewed by the authors. The final selection consisted of 24 articles. Of the selected articles, 21 dealt with access policies in electronic health records systems. Eleven articles discussed whether access to electronic health records should be granted by patients or by health organizations. Wireless environments were only considered in three articles. Finally, only four articles explicitly mentioned that technical training of staff and/or patients is required. Role-based access control is the preferred mechanism to deploy access policy by the designers of electronic health records. In most systems, access control is managed by users and health professionals, which promotes patients' right to control personal information. Finally, the security of wireless environments is not usually considered. However, one line of research is eHealth in mobile environments, called mHealth. Copyright © 2011 SESPAS. Published by Elsevier Espana. All rights reserved.
Shrestha, Bharat; Hossain, Ekram; Camorlinga, Sergio
2011-09-01
In wireless personal area networks, such as wireless body-area sensor networks, stations or devices have different bandwidth requirements and, thus, create heterogeneous traffics. For such networks, the IEEE 802.15.4 medium access control (MAC) can be used in the beacon-enabled mode, which supports guaranteed time slot (GTS) allocation for time-critical data transmissions. This paper presents a general discrete-time Markov chain model for the IEEE 802.15.4-based networks taking into account the slotted carrier sense multiple access with collision avoidance and GTS transmission phenomena together in the heterogeneous traffic scenario and under nonsaturated condition. For this purpose, the standard GTS allocation scheme is modified. For each non-identical device, the Markov model is solved and the average service time and the service utilization factor are analyzed in the non-saturated mode. The analysis is validated by simulations using network simulator version 2.33. Also, the model is enhanced with a wireless propagation model and the performance of the MAC is evaluated in a wheelchair body-area sensor network scenario.
How Well Does Medicaid Work in Improving Access to Care?
Long, Sharon K; Coughlin, Teresa; King, Jennifer
2005-01-01
Objective To provide an assessment of how well the Medicaid program is working at improving access to and use of health care for low-income mothers. Data Source/Study Setting The 1997 and 1999 National Survey of America's Families, with state and county information drawn from the Area Resource File and other sources. Study Design Estimate the effects of Medicaid on access and use relative to private coverage and being uninsured, using instrumental variables methods to control for selection into insurance status. Data Collection/Extraction Method This study combines data from 1997 and 1999 for mothers in families with incomes below 200 percent of the federal poverty level. Principal Findings We find that Medicaid beneficiaries' access and use are significantly better than those obtained by the uninsured. Analysis that controls for insurance selection shows that the benefits of having Medicaid coverage versus being uninsured are substantially larger than what is estimated when selection is not accounted for. Our results also indicate that Medicaid beneficiaries' access and use are comparable to that of the low-income privately insured. Once insurance selection is controlled for, access and use under Medicaid is not significantly different from access and use under private insurance. Without controls for insurance selection, access and use for Medicaid beneficiaries is found to be significantly worse than for the low-income privately insured. Conclusions Our results show that the Medicaid program improved access to care relative to uninsurance for low-income mothers, achieving access and use levels comparable to those of the privately insured. Our results also indicate that prior research, which generally has not controlled for selection into insurance coverage, has likely understated the gains of Medicaid relative to uninsurance and overstated the gains of private coverage relative to Medicaid. PMID:15663701
Evaluating the effectiveness of biometric access control systems
NASA Astrophysics Data System (ADS)
Lively, Valerie M.
2005-05-01
This paper describes the contribution by the National Safe Skies Alliance (Safe Skies) in operational testing of biometric access control systems under the guidance of the Transportation Security Administration (TSA). Safe Skies has been conducting operational tests of biometric access control systems on behalf of the TSA for approximately four years. The majority of this testing has occurred at the McGhee Tyson Airport (TYS) in Knoxville, Tennessee. Twelve separate biometric devices - eight fingerprint, facial, iris, hand geometry, and fingerprint and iris, have been tested to date. Tests were conducted at a TYS administrative door and different airports to evaluate the access control device under normal, abnormal, and attempt-to-defeat conditions.
Automating Access Control Logics in Simple Type Theory with LEO-II
NASA Astrophysics Data System (ADS)
Benzmüller, Christoph
Garg and Abadi recently proved that prominent access control logics can be translated in a sound and complete way into modal logic S4. We have previously outlined how normal multimodal logics, including monomodal logics K and S4, can be embedded in simple type theory and we have demonstrated that the higher-order theorem prover LEO-II can automate reasoning in and about them. In this paper we combine these results and describe a sound (and complete) embedding of different access control logics in simple type theory. Employing this framework we show that the off the shelf theorem prover LEO-II can be applied to automate reasoning in and about prominent access control logics.
Spatially explicit control of invasive species using a reaction-diffusion model
Bonneau, Mathieu; Johnson, Fred A.; Romagosa, Christina M.
2016-01-01
Invasive species, which can be responsible for severe economic and environmental damages, must often be managed over a wide area with limited resources, and the optimal allocation of effort in space and time can be challenging. If the spatial range of the invasive species is large, control actions might be applied only on some parcels of land, for example because of property type, accessibility, or limited human resources. Selecting the locations for control is critical and can significantly impact management efficiency. To help make decisions concerning the spatial allocation of control actions, we propose a simulation based approach, where the spatial distribution of the invader is approximated by a reaction–diffusion model. We extend the classic Fisher equation to incorporate the effect of control both in the diffusion and local growth of the invader. The modified reaction–diffusion model that we propose accounts for the effect of control, not only on the controlled locations, but on neighboring locations, which are based on the theoretical speed of the invasion front. Based on simulated examples, we show the superiority of our model compared to the state-of-the-art approach. We illustrate the use of this model for the management of Burmese pythons in the Everglades (Florida, USA). Thanks to the generality of the modified reaction–diffusion model, this framework is potentially suitable for a wide class of management problems and provides a tool for managers to predict the effects of different management strategies.
Levy, David; Fergus, Cristin; Rudov, Lindsey; McCormick-Ricket, Iben; Carton, Thomas
2016-02-01
Despite the presence of tobacco control policies, Louisiana continues to experience a high smoking burden and elevated smoking-attributable deaths. The SimSmoke model provides projections of these health outcomes in the face of existing and expanded (simulated) tobacco control polices. The SimSmoke model utilizes population data, smoking rates, and various tobacco control policy measures from Louisiana to predict smoking prevalence and smoking-attributable deaths. The model begins in 1993 and estimates are projected through 2054. The model is validated against existing Louisiana smoking prevalence data. The most powerful individual policy measure for reducing smoking prevalence is cigarette excise tax. However, a comprehensive cessation treatment policy is predicted to save the most lives. A combination of tobacco control policies provides the greatest reduction in smoking prevalence and smoking-attributable deaths. The existing Louisiana excise tax ranks as one of the lowest in the country and the legislature is against further increases. Alternative policy measures aimed at lowering prevalence and attributable deaths are: cessation treatments, comprehensive smoke-free policies, and limiting youth access. These three policies have a substantial effect on smoking prevalence and attributable deaths and are likely to encounter more favor in the Louisiana legislature than increasing the state excise tax.
42 CFR 431.834 - Access to records: Claims processing assessment systems.
Code of Federal Regulations, 2010 CFR
2010-10-01
... ADMINISTRATION Quality Control Medicaid Quality Control (mqc) Claims Processing Assessment System § 431.834 Access to records: Claims processing assessment systems. The agency, upon written request, must provide HHS staff with access to all records pertaining to its MQC claims processing assessment system reviews...
ERIC Educational Resources Information Center
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…
National treatment programme of hepatitis C in Egypt: Hepatitis C virus model of care.
El-Akel, W; El-Sayed, M H; El Kassas, M; El-Serafy, M; Khairy, M; Elsaeed, K; Kabil, K; Hassany, M; Shawky, A; Yosry, A; Shaker, M K; ElShazly, Y; Waked, I; Esmat, G; Doss, W
2017-04-01
Hepatitis C virus (HCV) infection is a major health problem in Egypt as the nation bears the highest prevalence rate worldwide. This necessitated establishing a novel model of care (MOC) to contain the epidemic, deliver patient care and ensure global treatment access. In this review, we describe the process of development of the Egyptian model and future strategies for sustainability. Although the magnitude of the HCV problem was known for many years, the HCV MOC only came into being in 2006 with the establishment of the National Committee for Control of Viral Hepatitis (NCCVH) to set up and implement a national control strategy for the disease and other causes of viral hepatitis. The strategy outlines best practices for patient care delivery by applying a set of service principles through identified clinical streams and patient flow continuums. The Egyptian national viral hepatitis treatment programme is considered one of the most successful and effective public health programmes. To date, more than one million patients were evaluated and more than 850 000 received treatment under the umbrella of the programme since 2006. The NCCVH has been successful in establishing a strong infrastructure for controlling viral hepatitis in Egypt. It established a nationwide network of digitally connected viral hepatitis-specialized treatment centres covering the country map to enhance treatment access. Practice guidelines suiting local circumstances were issued and regularly updated and are applied in all affiliated centres. This review illustrates the model and the successful Egyptian experience. It sets an exemplar for states, organizations and policy-makers setting up programmes for care and management of people with hepatitis C. © 2017 John Wiley & Sons Ltd.
Development and Use of a Virtual NMR Facility
NASA Astrophysics Data System (ADS)
Keating, Kelly A.; Myers, James D.; Pelton, Jeffrey G.; Bair, Raymond A.; Wemmer, David E.; Ellis, Paul D.
2000-03-01
We have developed a "virtual NMR facility" (VNMRF) to enhance access to the NMR spectrometers in Pacific Northwest National Laboratory's Environmental Molecular Sciences Laboratory (EMSL). We use the term virtual facility to describe a real NMR facility made accessible via the Internet. The VNMRF combines secure remote operation of the EMSL's NMR spectrometers over the Internet with real-time videoconferencing, remotely controlled laboratory cameras, real-time computer display sharing, a Web-based electronic laboratory notebook, and other capabilities. Remote VNMRF users can see and converse with EMSL researchers, directly and securely control the EMSL spectrometers, and collaboratively analyze results. A customized Electronic Laboratory Notebook allows interactive Web-based access to group notes, experimental parameters, proposed molecular structures, and other aspects of a research project. This paper describes our experience developing a VNMRF and details the specific capabilities available through the EMSL VNMRF. We show how the VNMRF has evolved during a test project and present an evaluation of its impact in the EMSL and its potential as a model for other scientific facilities. All Collaboratory software used in the VNMRF is freely available from http://www.emsl.pnl.gov:2080/docs/collab.
Diagnosing students' misconceptions in algebra: results from an experimental pilot study.
Russell, Michael; O'Dwyer, Laura M; Miranda, Helena
2009-05-01
Computer-based diagnostic assessment systems hold potential to help teachers identify sources of poor performance and to connect teachers and students to learning activities designed to help advance students' conceptual understandings. The present article presents findings from a study that examined how students' performance in algebra and their overcoming of common algebraic misconceptions were affected by the use of a diagnostic assessment system that focused on important algebra concepts. This study used a four-group randomized cluster trial design in which teachers were assigned randomly to one of four groups: a "business as usual" control group, a partial intervention group that was provided with access to diagnostic tests results, a partial intervention group that was provided with access to the learning activities, and a full intervention group that was given access to the test results and learning activities. Data were collected from 905 students (6th-12th grade) nested within 44 teachers. We used hierarchical linear modeling techniques to compare the effects of full, partial, and no (control) intervention on students' algebraic ability and misconceptions. The analyses indicate that full intervention had a net positive effect on ability and misconception measures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Theodore Larrieu, Christopher Slominski, Michele Joyce
2011-03-01
With the inauguration of the CEBAF Element Database (CED) in Fall 2010, Jefferson Lab computer scientists have taken a step toward the eventual goal of a model-driven accelerator. Once fully populated, the database will be the primary repository of information used for everything from generating lattice decks to booting control computers to building controls screens. A requirement influencing the CED design is that it provide access to not only present, but also future and past configurations of the accelerator. To accomplish this, an introspective database schema was designed that allows new elements, types, and properties to be defined on-the-fly withmore » no changes to table structure. Used in conjunction with Oracle Workspace Manager, it allows users to query data from any time in the database history with the same tools used to query the present configuration. Users can also check-out workspaces to use as staging areas for upcoming machine configurations. All Access to the CED is through a well-documented Application Programming Interface (API) that is translated automatically from original C++ source code into native libraries for scripting languages such as perl, php, and TCL making access to the CED easy and ubiquitous.« less
Adjacency Matrix-Based Transmit Power Allocation Strategies in Wireless Sensor Networks
Consolini, Luca; Medagliani, Paolo; Ferrari, Gianluigi
2009-01-01
In this paper, we present an innovative transmit power control scheme, based on optimization theory, for wireless sensor networks (WSNs) which use carrier sense multiple access (CSMA) with collision avoidance (CA) as medium access control (MAC) protocol. In particular, we focus on schemes where several remote nodes send data directly to a common access point (AP). Under the assumption of finite overall network transmit power and low traffic load, we derive the optimal transmit power allocation strategy that minimizes the packet error rate (PER) at the AP. This approach is based on modeling the CSMA/CA MAC protocol through a finite state machine and takes into account the network adjacency matrix, depending on the transmit power distribution and determining the network connectivity. It will be then shown that the transmit power allocation problem reduces to a convex constrained minimization problem. Our results show that, under the assumption of low traffic load, the power allocation strategy, which guarantees minimal delay, requires the maximization of network connectivity, which can be equivalently interpreted as the maximization of the number of non-zero entries of the adjacency matrix. The obtained theoretical results are confirmed by simulations for unslotted Zigbee WSNs. PMID:22346705
UNIX security in a supercomputing environment
NASA Technical Reports Server (NTRS)
Bishop, Matt
1989-01-01
The author critiques some security mechanisms in most versions of the Unix operating system and suggests more effective tools that either have working prototypes or have been implemented, for example in secure Unix systems. Although no computer (not even a secure one) is impenetrable, breaking into systems with these alternate mechanisms will cost more, require more skill, and be more easily detected than penetrations of systems without these mechanisms. The mechanisms described fall into four classes (with considerable overlap). User authentication at the local host affirms the identity of the person using the computer. The principle of least privilege dictates that properly authenticated users should have rights precisely sufficient to perform their tasks, and system administration functions should be compartmentalized; to this end, access control lists or capabilities should either replace or augment the default Unix protection system, and mandatory access controls implementing multilevel security models and integrity mechanisms should be available. Since most users access supercomputing environments using networks, the third class of mechanisms augments authentication (where feasible). As no security is perfect, the fourth class of mechanism logs events that may indicate possible security violations; this will allow the reconstruction of a successful penetration (if discovered), or possibly the detection of an attempted penetration.
CAS. Controlled Access Security
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martinez, B.; Pomeroy, G.
1989-12-01
The Security Alarm System is a data acquisition and control system which collects data from intrusion sensors and displays the information in a real-time environment for operators. The Access Control System monitors and controls the movement of personnel with the use of card readers and biometrics hand readers.
Sanchez, Victoria; Moore, Catherine F; Brunzell, Darlene H; Lynch, Wendy J
2014-04-01
Wheel running attenuates nicotine-seeking in male adolescent rats; however, it is not known if this effect extends to females. To determine if wheel running during abstinence would differentially attenuate subsequent nicotine-seeking in male and female rats that had extended access to nicotine self-administration during adolescence. Male (n = 49) and female (n = 43) adolescent rats self-administered saline or nicotine (5 μg/kg) under an extended access (23-h) paradigm. Following the last self-administration session, rats were moved to polycarbonate cages for an abstinence period where they either had access to a locked or unlocked running wheel for 2 h/day. Subsequently, nicotine-seeking was examined under a within-session extinction/cue-induced reinstatement paradigm. Due to low levels of nicotine-seeking in females in both wheel groups, additional groups were included that were housed without access to a running wheel during abstinence. Females self-administered more nicotine as compared to males; however, within males and females, intake did not differ between groups prior to wheel assignment. Compared to saline controls, males and females that self-administered nicotine showed a significant increase in drug-seeking during extinction. Wheel running during abstinence attenuated nicotine-seeking during extinction in males. In females, access to either locked or unlocked wheels attenuated nicotine-seeking during extinction. While responding was reinstated by cues in both males and females, levels were modest and not significantly affected by exercise in this adolescent-onset model. While wheel running reduced subsequent nicotine-seeking in males, access to a wheel, either locked or unlocked, was sufficient to suppress nicotine-seeking in females.
Sanchez, Victoria; Moore, Catherine F; Brunzell, Darlene H; Lynch, Wendy J
2014-01-01
Rationale Wheel running attenuates nicotine-seeking in male adolescent rats; however it is not known if this effect extends to females. Objective To determine if wheel running during abstinence would differentially attenuate subsequent nicotine-seeking in male and female rats that had extended access to nicotine self-administration during adolescence. Methods Male (N = 49) and female (N = 43) adolescent rats self-administered saline or nicotine (5μg/kg) under an extended access (23-hour) paradigm. Following the last self-administration session, rats were moved to polycarbonate cages for an abstinence period where they either had access to a locked or unlocked running wheel for 2-hours/day. Subsequently, nicotine-seeking was examined under a within-session extinction/cue-induced reinstatement paradigm. Due to low levels of nicotine-seeking in females in both wheel groups, additional groups were included that were housed without access to a running wheel during abstinence. Results Females self-administered more nicotine as compared to males; however, within males and females, intake did not differ between groups prior to wheel assignment. Compared to saline controls, males and females that self-administered nicotine showed a significant increase in drug-seeking during extinction. Wheel running during abstinence attenuated nicotine-seeking during extinction in males. In females, access to either locked or unlocked wheels attenuated nicotine-seeking during extinction. While responding was reinstated by cues in both males and females, levels were modest and not significantly affected by exercise in this adolescent-onset model. Conclusions While wheel running reduced subsequent nicotine-seeking in males, access to a wheel, either locked or unlocked, was sufficient to suppress nicotine-seeking in females. PMID:24271035
ERIC Educational Resources Information Center
Dell, Gary S.; Martin, Nadine; Schwartz, Myrna F.
2007-01-01
Lexical access in language production, and particularly pathologies of lexical access, are often investigated by examining errors in picture naming and word repetition. In this article, we test a computational approach to lexical access, the two-step interactive model, by examining whether the model can quantitatively predict the repetition-error…
Stably accessing octave-spanning microresonator frequency combs in the soliton regime
Li, Qing; Briles, Travis C.; Westly, Daron A.; Drake, Tara E.; Stone, Jordan R.; Ilic, B. Robert; Diddams, Scott A.; Papp, Scott B.; Srinivasan, Kartik
2017-01-01
Microresonator frequency combs can be an enabling technology for optical frequency synthesis and timekeeping in low size, weight, and power architectures. Such systems require comb operation in low-noise, phase-coherent states such as solitons, with broad spectral bandwidths (e.g., octave-spanning) for self-referencing to detect the carrier-envelope offset frequency. However, accessing such states is complicated by thermo-optic dispersion. For example, in the Si3N4 platform, precisely dispersion-engineered structures can support broadband operation, but microsecond thermal time constants often require fast pump power or frequency control to stabilize the solitons. In contrast, here we consider how broadband soliton states can be accessed with simple pump laser frequency tuning, at a rate much slower than the thermal dynamics. We demonstrate octave-spanning soliton frequency combs in Si3N4 microresonators, including the generation of a multi-soliton state with a pump power near 40 mW and a single-soliton state with a pump power near 120 mW. We also develop a simplified two-step analysis to explain how these states are accessed without fast control of the pump laser, and outline the required thermal properties for such operation. Our model agrees with experimental results as well as numerical simulations based on a Lugiato-Lefever equation that incorporates thermo-optic dispersion. Moreover, it also explains an experimental observation that a member of an adjacent mode family on the red-detuned side of the pump mode can mitigate the thermal requirements for accessing soliton states. PMID:28603754
Effective Materials Property Information Management for the 21st Century
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ren, Weiju; Cebon, David; Arnold, Steve
2010-01-01
This paper discusses key principles for the development of materials property information management software systems. There are growing needs for automated materials information management in industry, research organizations and government agencies. In part these are fuelled by the demands for higher efficiency in material testing, product design and development and engineering analysis. But equally important, organizations are being driven to employ sophisticated methods and software tools for managing their mission-critical materials information by the needs for consistency, quality and traceability of data, as well as control of access to proprietary or sensitive information. Furthermore the use of increasingly sophisticated nonlinear,more » anisotropic and multi-scale engineering analysis approaches, particularly for composite materials, requires both processing of much larger volumes of test data for development of constitutive models and much more complex materials data input requirements for Computer-Aided Engineering (CAE) software. And finally, the globalization of engineering processes and outsourcing of design and development activities generates much greater needs for sharing a single gold source of materials information between members of global engineering teams in extended supply-chains. Fortunately material property management systems have kept pace with the growing user demands. They have evolved from hard copy archives, through simple electronic databases, to versatile data management systems that can be customized to specific user needs. The more sophisticated of these provide facilities for: (i) data management functions such as access control, version control, and quality control; (ii) a wide range of data import, export and analysis capabilities; (iii) mechanisms for ensuring that all data is traceable to its pedigree sources: details of testing programs, published sources, etc; (iv) tools for searching, reporting and viewing the data; and (v) access to the information via a wide range of interfaces, including web browsers, rich clients, programmatic access and clients embedded in third-party applications, such as CAE systems. This paper discusses the important requirements for advanced material data management systems as well as the future challenges and opportunities such as automated error checking, automated data quality assessment and characterization, identification of gaps in data, as well as functionalities and business models to keep users returning to the source: to generate user demand to fuel database growth and maintenance.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-26
... DEPARTMENT OF VETERANS AFFAIRS [OMB Control No. 2900-0739] Agency Information Collection (Access...) of 1995 (44 U.S.C. 3501-3521), this notice announces that the Veterans Benefits Administration (VBA... . Please refer to ``OMB Control No. 2900-0739.'' SUPPLEMENTARY INFORMATION: Title: Access to Financial...
Urban Studies: A Study of Bibliographic Access and Control.
ERIC Educational Resources Information Center
Anderson, Barbara E.
This paper analyzes: (1) the bibliographic access to publications in urban studies via printed secondary sources; (2) development and scope of classification systems and of vocabulary control for urban studies; and (3) currently accessible automated collections of bibliographic citations. Urban studies is defined as "an agglomeration of…
Neighborhood social capital and adult health: an empirical test of a Bourdieu-based model.
Carpiano, Richard M
2007-09-01
Drawing upon Bourdieu's [1986. The forms of capital. In: Richardson, J.G. (Ed.), Handbook of Theory and Research for the Sociology of Education. Greenwood, New York, pp. 241-258.] social capital theory, I test a conceptual model of neighborhood conditions and social capital - considering relationships between neighborhood social capital forms (social support, social leverage, informal social control, and neighborhood organization participation) and adult health behaviors (smoking, binge drinking) and perceived health, as well as interactions between neighborhood social capital and individuals' access to that social capital. Analyzing Los Angeles Family and Neighborhood Survey data linked with tract level census data, results suggest that specific social capital forms were directly associated with both positive and negative health outcomes. Additionally, residents' neighborhood attachment moderated relationships between various social capital forms and health. Future studies should consider social capital resources and the role of differential access to such resources for promoting or compromising health.
ERIC Educational Resources Information Center
Collister, Rupert
The Western model of education is based on reductionism and linear thinking motivated by profit for those at the top. Globalization is the zenith of this Western reductionist philosophy. Its proponents talk about technology providing access to new vocational opportunities, yet fewer people control more of the resources and services. People find…
Efficient Authorization of Rich Presence Using Secure and Composed Web Services
NASA Astrophysics Data System (ADS)
Li, Li; Chou, Wu
This paper presents an extended Role-Based Access Control (RBAC) model for efficient authorization of rich presence using secure web services composed with an abstract presence data model. Following the information symmetry principle, the standard RBAC model is extended to support context sensitive social relations and cascaded authority. In conjunction with the extended RBAC model, we introduce an extensible presence architecture prototype using WS-Security and WS-Eventing to secure rich presence information exchanges based on PKI certificates. Applications and performance measurements of our presence system are presented to show that the proposed RBAC framework for presence and collaboration is well suited for real-time communication and collaboration.
Ellaway, A; Macdonald, L; Kearns, A
2016-01-01
Background It is usually assumed that housing tenure and car access are associated with health simply because they are acting as markers for social class or income and wealth. However, previous studies conducted in the late 1990s found that these household assets were associated with health independently of social class and income. Here, we set out to examine if this is still the case. Methods We use data from our 2010 postal survey of a random sample of adults (n=2092) in 8 local authority areas in the West of Scotland. Self-reported health measures included limiting longstanding illness (LLSI), general health over the last year and the Hospital Anxiety and Depression Scale. Results We found a statistically significant relationship between housing tenure and all 4 health measures, regardless of the inclusion of social class or income as controls. Compared with owner occupiers, social renters were more likely to report ill-health (controlling for social class—LLSI OR: 3.24, general health OR: 2.82, anxiety η2: 0.031, depression η2: 0.048, controlling for income—LLSI OR: 3.28, general health OR: 2.82, anxiety η2: 0.033, depression η2: 0.057) (p<0.001 for all models). Car ownership was independently associated with depression and anxiety, with non-owners at higher risk of both (controlling for income—anxiety η2: 0.010, depression η2: 0.023, controlling for social class—anxiety η2: 0.013, depression η2: 0.033) (p<0.001 for all models). Conclusions Our results show that housing tenure and car ownership are still associated with health, after taking known correlates (age, sex, social class, income) into account. Further research is required to unpack some of the features of these household assets such as the quality of the dwelling and access to and use of different forms of transport to determine what health benefits or disbenefits they may be associated with in different contexts. PMID:27807086
A mathematical model of nutrient influence on fungal competition.
Jabed A Choudhury, M; M J Trevelyan, Philip; P Boswell, Graeme
2018-02-07
Fungi have a well-established role in nutrient cycling and are widely used as agents in biological control and in the remediation of polluted landscapes. Competition for resources between different fungal communities is common in these contexts and its outcome impacts on the success of such biotechnological applications. In this investigation a mathematical model is constructed to represent competition between two fungal colonies that have access to different resources. It is shown that the model equations display a multitude of travelling wave solutions and that the outcome of competition between two fungal biomasses can be controlled through the simple manipulation of the nutrient resources available to each. The model equations are also numerically integrated to illustrate the range of outcomes arising from fungal competition and these results are placed in context of established experimental observations. Copyright © 2017 Elsevier Ltd. All rights reserved.
Pencarrick Hertzman, Caitlin; Meagher, Nancy; McGrail, Kimberlyn M
2013-01-01
Population Data BC (PopData) is an innovative leader in facilitating access to linked data for population health research. Researchers from academic institutions across Canada work with PopData to submit data access requests for projects involving linked administrative data, with or without their own researcher-collected data. PopData and its predecessor-the British Columbia Linked Health Database-have facilitated over 350 research projects analyzing a broad spectrum of population health issues. PopData embeds privacy in every aspect of its operations. This case study focuses on how implementing the Privacy by Design model protects privacy while supporting access to individual-level data for research in the public interest. It explores challenges presented by legislation, stewardship, and public perception and demonstrates how PopData achieves both operational efficiencies and due diligence.
Pencarrick Hertzman, Caitlin; Meagher, Nancy; McGrail, Kimberlyn M
2013-01-01
Population Data BC (PopData) is an innovative leader in facilitating access to linked data for population health research. Researchers from academic institutions across Canada work with PopData to submit data access requests for projects involving linked administrative data, with or without their own researcher-collected data. PopData and its predecessor—the British Columbia Linked Health Database—have facilitated over 350 research projects analyzing a broad spectrum of population health issues. PopData embeds privacy in every aspect of its operations. This case study focuses on how implementing the Privacy by Design model protects privacy while supporting access to individual-level data for research in the public interest. It explores challenges presented by legislation, stewardship, and public perception and demonstrates how PopData achieves both operational efficiencies and due diligence. PMID:22935136
Seroussi, Brigitte; Bouaud, Jacques
2017-01-01
If the wide adoption of electronic health records (EHRs) is necessary to address health information sharing and care coordination issues, it is not sufficient. In order to address health information sharing, some countries, among which, France, have implemented a centralized framework with "new" nationwide care records. The French DMP is a centralized, nationally shared, electronic medical record, created according to the opt-in model. More than five years after the launching of the DMP project, DMPs have been created for 1.5% of the target population, which demonstrates the poor adoption of the tool by healthcare professionals. Among the 583,997 existing DMPs in June 2016, 41% were empty, and 24% of non-empty DMPs were actually accessed. If these "active" DMPs were equally accessed by both healthcare professionals and patients, patients accessed DMP documents four times more than healthcare professionals.
Bilingual lexical access in context: evidence from eye movements during reading.
Libben, Maya R; Titone, Debra A
2009-03-01
Current models of bilingualism (e.g., BIA+) posit that lexical access during reading is not language selective. However, much of this research is based on the comprehension of words in isolation. The authors investigated whether nonselective access occurs for words embedded in biased sentence contexts (e.g., A. I. Schwartz & J. F. Kroll, 2006). Eye movements were recorded as French-English bilinguals read English sentences containing cognates (e.g., piano), interlingual homographs (e.g., coin, meaning corner in French), or matched control words. Sentences provided a low or high semantic constraint for target-language meanings. Both early-stage comprehension measures (e.g., first fixation duration, gaze duration, and skipping) and late-stage comprehension measures (e.g., go-past time and total reading time) showed significant cognate facilitation and interlingual homograph interference for low-constraint sentences. For high-constraint sentences, however, only early-stage comprehension measures were consistent with nonselective access. There was no evidence of cognate facilitation or interlingual homograph interference for late-stage comprehension measures. Thus, nonselective bilingual lexical access at early stages of comprehension is rapidly resolved in semantically biased contexts at later stages of comprehension. (c) 2009 APA, all rights reserved
The advanced qualtiy control techniques planned for the Internation Soil Moisture Network
NASA Astrophysics Data System (ADS)
Xaver, A.; Gruber, A.; Hegiova, A.; Sanchis-Dufau, A. D.; Dorigo, W. A.
2012-04-01
In situ soil moisture observations are essential to evaluate and calibrate modeled and remotely sensed soil moisture products. Although a number of meteorological networks and field campaigns measuring soil moisture exist on a global and long-term scale, their observations are not easily accessible and lack standardization of both technique and protocol. Thus, handling and especially comparing these datasets with satellite products or land surface models is a demanding issue. To overcome these limitations the International Soil Moisture Network (ISMN; http://www.ipf.tuwien.ac.at/insitu/) has been initiated to act as a centralized data hosting facility. One advantage of the ISMN is that users are able to access the harmonized datasets easily through a web portal. Another advantage is the fully automated processing chain including the data harmonization in terms of units and sampling interval, but even more important is the advanced quality control system each measurement has to run through. The quality of in situ soil moisture measurements is crucial for the validation of satellite- and model-based soil moisture retrievals; therefore a sophisticated quality control system was developed. After a check for plausibility and geophysical limits a quality flag is added to each measurement. An enhanced flagging mechanism was recently defined using a spectrum based approach to detect spurious spikes, jumps and plateaus. The International Soil Moisture Network has already evolved to one of the most important distribution platforms for in situ soil moisture observations and is still growing. Currently, data from 27 networks in total covering more than 800 stations in Europe, North America, Australia, Asia and Africa is hosted by the ISMN. Available datasets also include historical datasets as well as near real-time measurements. The improved quality control system will provide important information for satellite-based as well as land surface model-based validation studies.
Visits to Registered Nurses: An Opportunity to Increase Contraceptive Access in California.
Parker, Emese C; Kong, Kevin; Watts, Leslie A; Schwarz, Eleanor B; Darney, Philip D; Thiel de Bocanegra, Heike
In 2013, California passed Assembly Bill (A.B.) 2348, approving registered nurses (RNs) to dispense patient self-administered hormonal contraceptives and administer injections of hormonal contraceptives. The Family Planning, Access, Care and Treatment (Family PACT) program, which came into effect in 1997 to expand low-income, uninsured California resident access to contraceptives at no cost, is one program in which qualified RNs can dispense and administer contraceptives. The aims of this study were to (a) describe utilization of RN visits within California's Family PACT program and (b) evaluate the impact of RN visits on client birth control acquisition during the first 18 months after implementation of A.B. 2348 (January 1, 2013 to June 30, 2014). A descriptive observational design using administrative databases was used. Family PACT claims were retrieved for RN visits and contraception. Paid claims for contraceptive dispensing and/or administration visits by physicians, nurse practitioners, certified nurse midwives, and physician assistants were compared before and after the implementation of A.B. 2348 at practice sites where RN visits were and were not utilized. Contraceptive methods and administration procedures were identified using Healthcare Common Procedure Coding System codes, National Drug Codes, and Common Procedural Terminology codes. Claims data for healthcare facilities were abstracted by site location based on a unique combination of National Provider Identifier (NPI), NPI Owner, and NPI location number. RN visits were found mainly in Northern California and the Central Valley (73%). Sixty-eight percent of RN visits resulted in same-day dispensing and/or administration of hormonal (and/or barrier) methods. Since benefit implementation, RN visits resulted in a 10% increase in access to birth control dispensing and/or administration visits. RN visits were also associated with future birth control acquisition and other healthcare utilization within the subsequent 30 days. RN visits, though underutilized across the state, have resulted in increased access to contraception in some communities, an effect that may continue to grow with time and can serve as a model for other states.
Open access publishing, article downloads, and citations: randomised controlled trial
Lewenstein, Bruce V; Simon, Daniel H; Booth, James G; Connolly, Mathew J L
2008-01-01
Objective To measure the effect of free access to the scientific literature on article downloads and citations. Design Randomised controlled trial. Setting 11 journals published by the American Physiological Society. Participants 1619 research articles and reviews. Main outcome measures Article readership (measured as downloads of full text, PDFs, and abstracts) and number of unique visitors (internet protocol addresses). Citations to articles were gathered from the Institute for Scientific Information after one year. Interventions Random assignment on online publication of articles published in 11 scientific journals to open access (treatment) or subscription access (control). Results Articles assigned to open access were associated with 89% more full text downloads (95% confidence interval 76% to 103%), 42% more PDF downloads (32% to 52%), and 23% more unique visitors (16% to 30%), but 24% fewer abstract downloads (−29% to −19%) than subscription access articles in the first six months after publication. Open access articles were no more likely to be cited than subscription access articles in the first year after publication. Fifty nine per cent of open access articles (146 of 247) were cited nine to 12 months after publication compared with 63% (859 of 1372) of subscription access articles. Logistic and negative binomial regression analysis of article citation counts confirmed no citation advantage for open access articles. Conclusions Open access publishing may reach more readers than subscription access publishing. No evidence was found of a citation advantage for open access articles in the first year after publication. The citation advantage from open access reported widely in the literature may be an artefact of other causes. PMID:18669565
Simscape Modeling Verification in the Simulink Development Environment
NASA Technical Reports Server (NTRS)
Volle, Christopher E. E.
2014-01-01
The purpose of the Simulation Product Group of the Control and Data Systems division of the NASA Engineering branch at Kennedy Space Center is to provide a realtime model and simulation of the Ground Subsystems participating in vehicle launching activities. The simulation software is part of the Spaceport Command and Control System (SCCS) and is designed to support integrated launch operation software verification, and console operator training. Using Mathworks Simulink tools, modeling engineers currently build models from the custom-built blocks to accurately represent ground hardware. This is time consuming and costly due to required rigorous testing and peer reviews to be conducted for each custom-built block. Using Mathworks Simscape tools, modeling time can be reduced since there would be no custom-code developed. After careful research, the group came to the conclusion it is feasible to use Simscape's blocks in MatLab's Simulink. My project this fall was to verify the accuracy of the Crew Access Arm model developed using Simscape tools running in the Simulink development environment.
Modeling Virus Coinfection to Inform Management of Maize Lethal Necrosis in Kenya.
Hilker, Frank M; Allen, Linda J S; Bokil, Vrushali A; Briggs, Cheryl J; Feng, Zhilan; Garrett, Karen A; Gross, Louis J; Hamelin, Frédéric M; Jeger, Michael J; Manore, Carrie A; Power, Alison G; Redinbaugh, Margaret G; Rúa, Megan A; Cunniffe, Nik J
2017-10-01
Maize lethal necrosis (MLN) has emerged as a serious threat to food security in sub-Saharan Africa. MLN is caused by coinfection with two viruses, Maize chlorotic mottle virus and a potyvirus, often Sugarcane mosaic virus. To better understand the dynamics of MLN and to provide insight into disease management, we modeled the spread of the viruses causing MLN within and between growing seasons. The model allows for transmission via vectors, soil, and seed, as well as exogenous sources of infection. Following model parameterization, we predict how management affects disease prevalence and crop performance over multiple seasons. Resource-rich farmers with large holdings can achieve good control by combining clean seed and insect control. However, crop rotation is often required to effect full control. Resource-poor farmers with smaller holdings must rely on rotation and roguing, and achieve more limited control. For both types of farmer, unless management is synchronized over large areas, exogenous sources of infection can thwart control. As well as providing practical guidance, our modeling framework is potentially informative for other cropping systems in which coinfection has devastating effects. Our work also emphasizes how mathematical modeling can inform management of an emerging disease even when epidemiological information remains scanty. [Formula: see text] Copyright © 2017 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .
Simione, Luca; Raffone, Antonino; Wolters, Gezinus; Salmas, Paola; Nakatani, Chie; Belardinelli, Marta Olivetti; van Leeuwen, Cees
2012-10-01
Two separate lines of study have clarified the role of selectivity in conscious access to visual information. Both involve presenting multiple targets and distracters: one simultaneously in a spatially distributed fashion, the other sequentially at a single location. To understand their findings in a unified framework, we propose a neurodynamic model for Visual Selection and Awareness (ViSA). ViSA supports the view that neural representations for conscious access and visuo-spatial working memory are globally distributed and are based on recurrent interactions between perceptual and access control processors. Its flexible global workspace mechanisms enable a unitary account of a broad range of effects: It accounts for the limited storage capacity of visuo-spatial working memory, attentional cueing, and efficient selection with multi-object displays, as well as for the attentional blink and associated sparing and masking effects. In particular, the speed of consolidation for storage in visuo-spatial working memory in ViSA is not fixed but depends adaptively on the input and recurrent signaling. Slowing down of consolidation due to weak bottom-up and recurrent input as a result of brief presentation and masking leads to the attentional blink. Thus, ViSA goes beyond earlier 2-stage and neuronal global workspace accounts of conscious processing limitations. PsycINFO Database Record (c) 2012 APA, all rights reserved.
A semi-automated vascular access system for preclinical models
NASA Astrophysics Data System (ADS)
Berry-Pusey, B. N.; Chang, Y. C.; Prince, S. W.; Chu, K.; David, J.; Taschereau, R.; Silverman, R. W.; Williams, D.; Ladno, W.; Stout, D.; Tsao, T. C.; Chatziioannou, A.
2013-08-01
Murine models are used extensively in biological and translational research. For many of these studies it is necessary to access the vasculature for the injection of biologically active agents. Among the possible methods for accessing the mouse vasculature, tail vein injections are a routine but critical step for many experimental protocols. To perform successful tail vein injections, a high skill set and experience is required, leaving most scientists ill-suited to perform this task. This can lead to a high variability between injections, which can impact experimental results. To allow more scientists to perform tail vein injections and to decrease the variability between injections, a vascular access system (VAS) that semi-automatically inserts a needle into the tail vein of a mouse was developed. The VAS uses near infrared light, image processing techniques, computer controlled motors, and a pressure feedback system to insert the needle and to validate its proper placement within the vein. The VAS was tested by injecting a commonly used radiolabeled probe (FDG) into the tail veins of five mice. These mice were then imaged using micro-positron emission tomography to measure the percentage of the injected probe remaining in the tail. These studies showed that, on average, the VAS leaves 3.4% of the injected probe in the tail. With these preliminary results, the VAS system demonstrates the potential for improving the accuracy of tail vein injections in mice.
Robinson, Thomas N.; Walters, Paul A.
1987-01-01
Computer-based health education has been employed in many settings. However, data on resultant behavior change are lacking. A randomized, controlled, prospective study was performed to test the efficacy of Stanford Health-Net in changing community health behaviors. Graduate and undergraduate students (N=1003) were randomly assigned to treatment and control conditions. The treatment group received access to Health-Net, a health promotion computer network emphasizing specific self-care and preventive strategies. Over a four month intervention period, 26% of the treatment group used Health-Net an average of 6.4 times each (range 1 to 97). Users rated Health-Net favorably. The mean number of ambulatory medical visits decreesed 22.5% more in the treatment group than in the control group (P<.05), while hospitalizations did not differ significantly between groups. In addition, perceived self-efficacy for preventing the acquisition of a STD and herpes increased 577% (P<.05) and 261% (P<.01) more, respectively, in the treatment group than in the control group. These findings suggest that access to Stanford Health-Net can result in significant health behavior change. The advantages of the network approach make it a potential model for other communities.
A development framework for distributed artificial intelligence
NASA Technical Reports Server (NTRS)
Adler, Richard M.; Cottman, Bruce H.
1989-01-01
The authors describe distributed artificial intelligence (DAI) applications in which multiple organizations of agents solve multiple domain problems. They then describe work in progress on a DAI system development environment, called SOCIAL, which consists of three primary language-based components. The Knowledge Object Language defines models of knowledge representation and reasoning. The metaCourier language supplies the underlying functionality for interprocess communication and control access across heterogeneous computing environments. The metaAgents language defines models for agent organization coordination, control, and resource management. Application agents and agent organizations will be constructed by combining metaAgents and metaCourier building blocks with task-specific functionality such as diagnostic or planning reasoning. This architecture hides implementation details of communications, control, and integration in distributed processing environments, enabling application developers to concentrate on the design and functionality of the intelligent agents and agent networks themselves.
46 CFR 154.320 - Cargo control stations.
Code of Federal Regulations, 2010 CFR
2010-10-01
...) If a cargo control station is in accommodation, service, or control spaces or has access to such a space, the station must: (1) Be a gas safe space; (2) Have an access to the space that meets § 154.330...
46 CFR 154.320 - Cargo control stations.
Code of Federal Regulations, 2011 CFR
2011-10-01
...) If a cargo control station is in accommodation, service, or control spaces or has access to such a space, the station must: (1) Be a gas safe space; (2) Have an access to the space that meets § 154.330...
Method and apparatus for managing access to a memory
DOE Office of Scientific and Technical Information (OSTI.GOV)
DeBenedictis, Erik
A method and apparatus for managing access to a memory of a computing system. A controller transforms a plurality of operations that represent a computing job into an operational memory layout that reduces a size of a selected portion of the memory that needs to be accessed to perform the computing job. The controller stores the operational memory layout in a plurality of memory cells within the selected portion of the memory. The controller controls a sequence by which a processor in the computing system accesses the memory to perform the computing job using the operational memory layout. The operationalmore » memory layout reduces an amount of energy consumed by the processor to perform the computing job.« less
Trends in communicative access solutions for children with cerebral palsy.
Myrden, Andrew; Schudlo, Larissa; Weyand, Sabine; Zeyl, Timothy; Chau, Tom
2014-08-01
Access solutions may facilitate communication in children with limited functional speech and motor control. This study reviews current trends in access solution development for children with cerebral palsy, with particular emphasis on the access technology that harnesses a control signal from the user (eg, movement or physiological change) and the output device (eg, augmentative and alternative communication system) whose behavior is modulated by the user's control signal. Access technologies have advanced from simple mechanical switches to machine vision (eg, eye-gaze trackers), inertial sensing, and emerging physiological interfaces that require minimal physical effort. Similarly, output devices have evolved from bulky, dedicated hardware with limited configurability, to platform-agnostic, highly personalized mobile applications. Emerging case studies encourage the consideration of access technology for all nonverbal children with cerebral palsy with at least nascent contingency awareness. However, establishing robust evidence of the effectiveness of the aforementioned advances will require more expansive studies. © The Author(s) 2014.
Re-designing the PhEDEx Security Model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huang, C.-H.; Wildish, T.; Zhang, X.
2014-01-01
PhEDEx, the data-placement tool used by the CMS experiment at the LHC, was conceived in a more trusting time. The security model provided a safe environment for site agents and operators, but offerred little more protection than that. Data was not sufficiently protected against loss caused by operator error or software bugs or by deliberate manipulation of the database. Operators were given high levels of access to the database, beyond what was actually needed to accomplish their tasks. This exposed them to the risk of suspicion should an incident occur. Multiple implementations of the security model led to difficulties maintainingmore » code, which can lead to degredation of security over time. In order to meet the simultaneous goals of protecting CMS data, protecting the operators from undue exposure to risk, increasing monitoring capabilities and improving maintainability of the security model, the PhEDEx security model was redesigned and re-implemented. Security was moved from the application layer into the database itself, fine-grained access roles were established, and tools and procedures created to control the evolution of the security model over time. In this paper we describe this work, we describe the deployment of the new security model, and we show how these enhancements improve security on several fronts simultaneously.« less
Re-designing the PhEDEx Security Model
NASA Astrophysics Data System (ADS)
C-H, Huang; Wildish, T.; X, Zhang
2014-06-01
PhEDEx, the data-placement tool used by the CMS experiment at the LHC, was conceived in a more trusting time. The security model provided a safe environment for site agents and operators, but offerred little more protection than that. Data was not sufficiently protected against loss caused by operator error or software bugs or by deliberate manipulation of the database. Operators were given high levels of access to the database, beyond what was actually needed to accomplish their tasks. This exposed them to the risk of suspicion should an incident occur. Multiple implementations of the security model led to difficulties maintaining code, which can lead to degredation of security over time. In order to meet the simultaneous goals of protecting CMS data, protecting the operators from undue exposure to risk, increasing monitoring capabilities and improving maintainability of the security model, the PhEDEx security model was redesigned and re-implemented. Security was moved from the application layer into the database itself, fine-grained access roles were established, and tools and procedures created to control the evolution of the security model over time. In this paper we describe this work, we describe the deployment of the new security model, and we show how these enhancements improve security on several fronts simultaneously.
Improved head direction command classification using an optimised Bayesian neural network.
Nguyen, Son T; Nguyen, Hung T; Taylor, Philip B; Middleton, James
2006-01-01
Assistive technologies have recently emerged to improve the quality of life of severely disabled people by enhancing their independence in daily activities. Since many of those individuals have limited or non-existing control from the neck downward, alternative hands-free input modalities have become very important for these people to access assistive devices. In hands-free control, head movement has been proved to be a very effective user interface as it can provide a comfortable, reliable and natural way to access the device. Recently, neural networks have been shown to be useful not only for real-time pattern recognition but also for creating user-adaptive models. Since multi-layer perceptron neural networks trained using standard back-propagation may cause poor generalisation, the Bayesian technique has been proposed to improve the generalisation and robustness of these networks. This paper describes the use of Bayesian neural networks in developing a hands-free wheelchair control system. The experimental results show that with the optimised architecture, classification Bayesian neural networks can detect head commands of wheelchair users accurately irrespective to their levels of injuries.
How Accurate Is A Hydraulic Model? | Science Inventory | US ...
Symposium paper Network hydraulic models are widely used, but their overall accuracy is often unknown. Models are developed to give utilities better insight into system hydraulic behavior, and increasingly the ability to predict the fate and transport of chemicals. Without an accessible and consistent means of validating a given model against the system it is meant to represent, the value of those supposed benefits should be questioned. Supervisory Control And Data Acquisition (SCADA) databases, though ubiquitous, are underused data sources for this type of task. Integrating a network model with a measurement database would offer professionals the ability to assess the model’s assumptions in an automated fashion by leveraging enormous amounts of data.
Environmental and Socio-Demographic Determinants of Dengue Fever in Colombo City, Sri Lanka
NASA Technical Reports Server (NTRS)
Tipre, Meghan; Luvall, Jeffrey; Haque, Akhlaque; McClure, Leslie; Zaitchik, Ben; Sathiakumar, Nalini
2014-01-01
Dengue fever has increased exponentially in Sri Lanka, from 24.4 cases per 100,000 in 2003 to 165.3 per 100,000 population in 2013. Although early warning systems using predictor models have been previously developed in other settings, it is important to develop such models in each local setting. Further, the ability of these models to be applicable at smaller geographic units will enhance current vector control and disease surveillance measures. The aim of this paper was to identify environmental and socio-economic status (SES) risk factors that may predict dengue fever at the Gram Niladhari Divisions (GND) level (smallest administrative unit) in Colombo city, Sri Lanka. These factors included landcover classes, amount of vegetation, population density, water access and neighborhood SES as determined by roof type. A geographically weighted regression (GWR) was used to develop the prediction model. A total 55 GND units covering an area of 37 sq km were investigated. We found that GND units with decreased vegetation, higher built-up area, higher population density and poor access to tap-water supply were associated with high risk of dengue; the pertinent GND units were concentrated in the center of the city. This is the first study in Sri Lanka to include both environmental and socio-demographic factors in prediction models for dengue fever. The methodology may be useful in enhancing ongoing dengue fever control measures in the country, and to be extended to other countries in the region that have an increasing incidence of dengue fever.
Guo, Hangwen; Noh, Joo H; Dong, Shuai; Rack, Philip D; Gai, Zheng; Xu, Xiaoshan; Dagotto, Elbio; Shen, Jian; Ward, T Zac
2013-08-14
Electronically phase separated manganite wires are found to exhibit controllable metal-insulator transitions under local electric fields. The switching characteristics are shown to be fully reversible, polarity independent, and highly resistant to thermal breakdown caused by repeated cycling. It is further demonstrated that multiple discrete resistive states can be accessed in a single wire. The results conform to a phenomenological model in which the inherent nanoscale insulating and metallic domains are rearranged through electrophoretic-like processes to open and close percolation channels.
Integrated semiconductor-magnetic random access memory system
NASA Technical Reports Server (NTRS)
Katti, Romney R. (Inventor); Blaes, Brent R. (Inventor)
2001-01-01
The present disclosure describes a non-volatile magnetic random access memory (RAM) system having a semiconductor control circuit and a magnetic array element. The integrated magnetic RAM system uses CMOS control circuit to read and write data magnetoresistively. The system provides a fast access, non-volatile, radiation hard, high density RAM for high speed computing.
Nelson, Karin; Sun, Haili; Dolan, Emily; Maynard, Charles; Beste, Laruen; Bryson, Christopher; Schectman, Gordon; Fihn, Stephan D
2014-01-01
Care continuity, access, and coordination are important features of the patient-centered medical home model and have been emphasized in the Veterans Health Administration patient-centered medical home implementation, called the Patient Aligned Care Team. Data from more than 4.3 million Veterans were used to assess the relationship between these attributes of Patient Aligned Care Team and Veterans Health Administration hospitalization and mortality. Controlling for demographics and comorbidity, we found that continuity with a primary care provider was associated with a lower likelihood of hospitalization and mortality among a large population of Veterans receiving VA primary care.
Memory-Intensive Benchmarks: IRAM vs. Cache-Based Machines
NASA Technical Reports Server (NTRS)
Biswas, Rupak; Gaeke, Brian R.; Husbands, Parry; Li, Xiaoye S.; Oliker, Leonid; Yelick, Katherine A.; Biegel, Bryan (Technical Monitor)
2002-01-01
The increasing gap between processor and memory performance has lead to new architectural models for memory-intensive applications. In this paper, we explore the performance of a set of memory-intensive benchmarks and use them to compare the performance of conventional cache-based microprocessors to a mixed logic and DRAM processor called VIRAM. The benchmarks are based on problem statements, rather than specific implementations, and in each case we explore the fundamental hardware requirements of the problem, as well as alternative algorithms and data structures that can help expose fine-grained parallelism or simplify memory access patterns. The benchmarks are characterized by their memory access patterns, their basic control structures, and the ratio of computation to memory operation.
Pattern of access determines influence of junk food diet on cue sensitivity and palatability.
Kosheleff, Alisa R; Araki, Jingwen; Hsueh, Jennifer; Le, Andrew; Quizon, Kevin; Ostlund, Sean B; Maidment, Nigel T; Murphy, Niall P
2018-04-01
Like drug addiction, cues associated with palatable foods can trigger food-seeking, even when sated. However, whether susceptibility to the motivating influence of food-related cues is a predisposing factor in overeating or a consequence of poor diet is difficult to determine in humans. Using a rodent model, we explored whether a highly palatable 'junk food' diet impacts responses to reward-paired cues in a Pavlovian-to-instrumental transfer test, using sweetened condensed milk (SCM) as the reward. The hedonic impact of SCM consumption was also assessed by analyzing licking microstructure. To probe the effects of pattern and duration of junk food exposure, we provided rats with either regular chow ad libitum (controls) or chow plus access to junk food for either 2 or 24 h per day for 1, 3, or 6 weeks. We also examined how individual susceptibility to weight gain related to these measures. Rats provided 24 h access to the junk food diet were insensitive to the motivational effects of a SCM-paired cue when tested sated even though their hedonic experience upon reward consumption was similar to controls. In contrast, rats provided restricted, 2 h access to junk food exhibited a cue generalization phenotype under sated conditions, lever-pressing with increased vigor in response to both a SCM-paired cue, and a cue not previously paired with reward. Hedonic response was also significantly higher in these animals relative to controls. These data demonstrate that the pattern of junk food exposure differentially alters the hedonic impact of palatable foods and susceptibility to the motivating influence of cues in the environment to promote food-seeking actions when sated, which may be consequential for understanding overeating and obesity. Copyright © 2017 Elsevier Ltd. All rights reserved.
46 CFR 154.320 - Cargo control stations.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Arrangements § 154.320 Cargo control stations. (a) Cargo control stations must be above the weather deck. (b) If a cargo control station is in accommodation, service, or control spaces or has access to such a space, the station must: (1) Be a gas safe space; (2) Have an access to the space that meets § 154.330...
46 CFR 154.320 - Cargo control stations.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Arrangements § 154.320 Cargo control stations. (a) Cargo control stations must be above the weather deck. (b) If a cargo control station is in accommodation, service, or control spaces or has access to such a space, the station must: (1) Be a gas safe space; (2) Have an access to the space that meets § 154.330...
46 CFR 154.320 - Cargo control stations.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Arrangements § 154.320 Cargo control stations. (a) Cargo control stations must be above the weather deck. (b) If a cargo control station is in accommodation, service, or control spaces or has access to such a space, the station must: (1) Be a gas safe space; (2) Have an access to the space that meets § 154.330...
Freedman, Darcy A; Blake, Christine E; Liese, Angela D
2013-01-01
Access to nutritious foods is limited in disenfranchised communities in the United States. Policies are beginning to focus on improving nutritious food access in these contexts; yet, few theories are available to guide this work. We developed a conceptual model of nutritious food access based on the qualitative responses of food consumers in 2 different regions of the American South. Five domains (economic, service delivery, spatial-temporal, social, and personal) and related dimensions of nutritious food access were identified. The conceptual model provides practical guidance to researchers, policy makers, and practitioners working to improve nutritious food access in communities.
FREEDMAN, DARCY A.; BLAKE, CHRISTINE E.; LIESE, ANGELA D.
2014-01-01
Access to nutritious foods is limited in disenfranchised communities in the United States. Policies are beginning to focus on improving nutritious food access in these contexts; yet, few theories are available to guide this work. We developed a conceptual model of nutritious food access based on the qualitative responses of food consumers in 2 different regions of the American South. Five domains (economic, service delivery, spatial–temporal, social, and personal) and related dimensions of nutritious food access were identified. The conceptual model provides practical guidance to researchers, policy makers, and practitioners working to improve nutritious food access in communities. PMID:24563605
S&MPO - An information system for ozone spectroscopy on the WEB
NASA Astrophysics Data System (ADS)
Babikov, Yurii L.; Mikhailenko, Semen N.; Barbe, Alain; Tyuterev, Vladimir G.
2014-09-01
Spectroscopy and Molecular Properties of Ozone ("S&MPO") is an Internet accessible information system devoted to high resolution spectroscopy of the ozone molecule, related properties and data sources. S&MPO contains information on original spectroscopic data (line positions, line intensities, energies, transition moments, spectroscopic parameters) recovered from comprehensive analyses and modeling of experimental spectra as well as associated software for data representation written in PHP Java Script, C++ and FORTRAN. The line-by-line list of vibration-rotation transitions and other information is organized as a relational database under control of MySQL database tools. The main S&MPO goal is to provide access to all available information on vibration-rotation molecular states and transitions under extended conditions based on extrapolations of laboratory measurements using validated theoretical models. Applications for the S&MPO may include: education/training in molecular physics, radiative processes, laser physics; spectroscopic applications (analysis, Fourier transform spectroscopy, atmospheric optics, optical standards, spectroscopic atlases); applications to environment studies and atmospheric physics (remote sensing); data supply for specific databases; and to photochemistry (laser excitation, multiphoton processes). The system is accessible via Internet on two sites: http://smpo.iao.ru and http://smpo.univ-reims.fr.
Griffiths, James; Carnegie, Amadeus; Kendall, Richard; Madan, Rajeev
2017-12-01
Ultrasound-guided peripheral intravenous access may present an alternative to central or intraosseous access in patients with difficult peripheral veins. Using venepuncture of a phantom model as a proxy, we investigated whether novice ultrasound users should adopt a cross-sectional or longitudinal approach when learning to access peripheral veins under ultrasound guidance. This result would inform the development of a structured training method for this procedure. We conducted a randomised controlled trial of 30 medical students. Subjects received 35 min of training, then attempted to aspirate 1 ml of synthetic blood from a deep vein in a training model under ultrasound guidance. Subjects attempted both the cross-sectional and longitudinal approaches. Group 1 used cross-sectional first, followed by longitudinal. Group 2 used longitudinal first, then cross-sectional. We measured the time from first puncture of the model's skin to aspiration of fluid, and the number of attempts required. Subjects also reported difficulty ratings for each approach. Paired sample t-tests were used for statistical analysis. The mean number of attempts was 1.13 using the cross-sectional approach, compared with 1.30 using the longitudinal approach (p = 0.17). Mean time to aspiration of fluid was 45.1 s using the cross-sectional approach and 52.8 s using the longitudinal approach (p = 0.43). The mean difficulty score out of 10 was 3.97 for the cross-sectional approach and 3.93 for the longitudinal approach (p = 0.95). We found no significant difference in effectiveness between the cross-sectional and longitudinal approaches to ultrasound-guided venepuncture when performed on a model. We believe that both approaches should be included when teaching ultrasound-guided peripheral vascular access. To confirm which approach would be best in clinical practice, we advocate future testing of both approaches on patients.
NASA Astrophysics Data System (ADS)
Markelov, Oleg; Nguyen Duc, Viet; Bogachev, Mikhail
2017-11-01
Recently we have suggested a universal superstatistical model of user access patterns and aggregated network traffic. The model takes into account the irregular character of end user access patterns on the web via the non-exponential distributions of the local access rates, but neglects the long-term correlations between these rates. While the model is accurate for quasi-stationary traffic records, its performance under highly variable and especially non-stationary access dynamics remains questionable. In this paper, using an example of the traffic patterns from a highly loaded network cluster hosting the website of the 1998 FIFA World Cup, we suggest a generalization of the previously suggested superstatistical model by introducing long-term correlations between access rates. Using queueing system simulations, we show explicitly that this generalization is essential for modeling network nodes with highly non-stationary access patterns, where neglecting long-term correlations leads to the underestimation of the empirical average sojourn time by several decades under high throughput utilization.
Ecosystem Services Flows: Why Stakeholders' Power Relationships Matter.
Felipe-Lucia, María R; Martín-López, Berta; Lavorel, Sandra; Berraquero-Díaz, Luis; Escalera-Reyes, Javier; Comín, Francisco A
2015-01-01
The ecosystem services framework has enabled the broader public to acknowledge the benefits nature provides to different stakeholders. However, not all stakeholders benefit equally from these services. Rather, power relationships are a key factor influencing the access of individuals or groups to ecosystem services. In this paper, we propose an adaptation of the "cascade" framework for ecosystem services to integrate the analysis of ecological interactions among ecosystem services and stakeholders' interactions, reflecting power relationships that mediate ecosystem services flows. We illustrate its application using the floodplain of the River Piedra (Spain) as a case study. First, we used structural equation modelling (SEM) to model the dependence relationships among ecosystem services. Second, we performed semi-structured interviews to identify formal power relationships among stakeholders. Third, we depicted ecosystem services according to stakeholders' ability to use, manage or impair ecosystem services in order to expose how power relationships mediate access to ecosystem services. Our results revealed that the strongest power was held by those stakeholders who managed (although did not use) those keystone ecosystem properties and services that determine the provision of other services (i.e., intermediate regulating and final services). In contrast, non-empowered stakeholders were only able to access the remaining non-excludable and non-rival ecosystem services (i.e., some of the cultural services, freshwater supply, water quality, and biological control). In addition, land stewardship, access rights, and governance appeared as critical factors determining the status of ecosystem services. Finally, we stress the need to analyse the role of stakeholders and their relationships to foster equal access to ecosystem services.
Ecosystem Services Flows: Why Stakeholders’ Power Relationships Matter
Felipe-Lucia, María R.; Martín-López, Berta; Lavorel, Sandra; Berraquero-Díaz, Luis; Escalera-Reyes, Javier; Comín, Francisco A.
2015-01-01
The ecosystem services framework has enabled the broader public to acknowledge the benefits nature provides to different stakeholders. However, not all stakeholders benefit equally from these services. Rather, power relationships are a key factor influencing the access of individuals or groups to ecosystem services. In this paper, we propose an adaptation of the “cascade” framework for ecosystem services to integrate the analysis of ecological interactions among ecosystem services and stakeholders’ interactions, reflecting power relationships that mediate ecosystem services flows. We illustrate its application using the floodplain of the River Piedra (Spain) as a case study. First, we used structural equation modelling (SEM) to model the dependence relationships among ecosystem services. Second, we performed semi-structured interviews to identify formal power relationships among stakeholders. Third, we depicted ecosystem services according to stakeholders’ ability to use, manage or impair ecosystem services in order to expose how power relationships mediate access to ecosystem services. Our results revealed that the strongest power was held by those stakeholders who managed (although did not use) those keystone ecosystem properties and services that determine the provision of other services (i.e., intermediate regulating and final services). In contrast, non-empowered stakeholders were only able to access the remaining non-excludable and non-rival ecosystem services (i.e., some of the cultural services, freshwater supply, water quality, and biological control). In addition, land stewardship, access rights, and governance appeared as critical factors determining the status of ecosystem services. Finally, we stress the need to analyse the role of stakeholders and their relationships to foster equal access to ecosystem services. PMID:26201000
Systematic plan of building Web geographic information system based on ActiveX control
NASA Astrophysics Data System (ADS)
Zhang, Xia; Li, Deren; Zhu, Xinyan; Chen, Nengcheng
2003-03-01
A systematic plan of building Web Geographic Information System (WebGIS) using ActiveX technology is proposed in this paper. In the proposed plan, ActiveX control technology is adopted in building client-side application, and two different schemas are introduced to implement communication between controls in users¡ browser and middle application server. One is based on Distribute Component Object Model (DCOM), the other is based on socket. In the former schema, middle service application is developed as a DCOM object that communicates with ActiveX control through Object Remote Procedure Call (ORPC) and accesses data in GIS Data Server through Open Database Connectivity (ODBC). In the latter, middle service application is developed using Java language. It communicates with ActiveX control through socket based on TCP/IP and accesses data in GIS Data Server through Java Database Connectivity (JDBC). The first one is usually developed using C/C++, and it is difficult to develop and deploy. The second one is relatively easy to develop, but its performance of data transfer relies on Web bandwidth. A sample application is developed using the latter schema. It is proved that the performance of the sample application is better than that of some other WebGIS applications in some degree.
Sociality influences cultural complexity.
Muthukrishna, Michael; Shulman, Ben W; Vasilescu, Vlad; Henrich, Joseph
2014-01-07
Archaeological and ethnohistorical evidence suggests a link between a population's size and structure, and the diversity or sophistication of its toolkits or technologies. Addressing these patterns, several evolutionary models predict that both the size and social interconnectedness of populations can contribute to the complexity of its cultural repertoire. Some models also predict that a sudden loss of sociality or of population will result in subsequent losses of useful skills/technologies. Here, we test these predictions with two experiments that permit learners to access either one or five models (teachers). Experiment 1 demonstrates that naive participants who could observe five models, integrate this information and generate increasingly effective skills (using an image editing tool) over 10 laboratory generations, whereas those with access to only one model show no improvement. Experiment 2, which began with a generation of trained experts, shows how learners with access to only one model lose skills (in knot-tying) more rapidly than those with access to five models. In the final generation of both experiments, all participants with access to five models demonstrate superior skills to those with access to only one model. These results support theoretical predictions linking sociality to cumulative cultural evolution.
Sociality influences cultural complexity
Muthukrishna, Michael; Shulman, Ben W.; Vasilescu, Vlad; Henrich, Joseph
2014-01-01
Archaeological and ethnohistorical evidence suggests a link between a population's size and structure, and the diversity or sophistication of its toolkits or technologies. Addressing these patterns, several evolutionary models predict that both the size and social interconnectedness of populations can contribute to the complexity of its cultural repertoire. Some models also predict that a sudden loss of sociality or of population will result in subsequent losses of useful skills/technologies. Here, we test these predictions with two experiments that permit learners to access either one or five models (teachers). Experiment 1 demonstrates that naive participants who could observe five models, integrate this information and generate increasingly effective skills (using an image editing tool) over 10 laboratory generations, whereas those with access to only one model show no improvement. Experiment 2, which began with a generation of trained experts, shows how learners with access to only one model lose skills (in knot-tying) more rapidly than those with access to five models. In the final generation of both experiments, all participants with access to five models demonstrate superior skills to those with access to only one model. These results support theoretical predictions linking sociality to cumulative cultural evolution. PMID:24225461
Physicians' fees and public medical care programs.
Lee, R H; Hadley, J
1981-01-01
In this article we develop and estimate a model of physicians' pricing that explicitly incorporates the effects of Medicare and Medicaid demand subsidies. Our analysis is based on a multiperiod model in which physicians are monopolistic competitors supplying services to several markets. The implications of the model are tested using data derived from claims submitted by a cohort of 1,200 California physicians during the years 1972-1975. We conclude that the demand for physician's services is relatively elastic; that increases in the local supply of physicians reduce prices somewhat; that physicians respond strategically to attempts to control prices through the customary-prevailing-reasonable system; and that price controls limit the rate of increase in physicians' prices. The analysis identifies a family of policies that recognize the monopsony power of public programs and may change the cost-access trade-off. PMID:7021479
2011-01-01
Background There is growing interest in the study of the relationships between individual health-related behaviours (e.g. food intake and physical activity) and measurements of spatial accessibility to the associated facilities (e.g. food outlets and sport facilities). The aim of this study is to propose measurements of spatial accessibility to facilities on the regional scale, using aggregated data. We first used a potential accessibility model that partly makes it possible to overcome the limitations of the most frequently used indices such as the count of opportunities within a given neighbourhood. We then propose an extended model in order to take into account both home and work-based accessibility for a commuting population. Results Potential accessibility estimation provides a very different picture of the accessibility levels experienced by the population than the more classical "number of opportunities per census tract" index. The extended model for commuters increases the overall accessibility levels but this increase differs according to the urbanisation level. Strongest increases are observed in some rural municipalities with initial low accessibility levels. Distance to major urban poles seems to play an essential role. Conclusions Accessibility is a multi-dimensional concept that should integrate some aspects of travel behaviour. Our work supports the evidence that the choice of appropriate accessibility indices including both residential and non-residential environmental features is necessary. Such models have potential implications for providing relevant information to policy-makers in the field of public health. PMID:21219597
Predicting clicks of PubMed articles.
Mao, Yuqing; Lu, Zhiyong
2013-01-01
Predicting the popularity or access usage of an article has the potential to improve the quality of PubMed searches. We can model the click trend of each article as its access changes over time by mining the PubMed query logs, which contain the previous access history for all articles. In this article, we examine the access patterns produced by PubMed users in two years (July 2009 to July 2011). We explore the time series of accesses for each article in the query logs, model the trends with regression approaches, and subsequently use the models for prediction. We show that the click trends of PubMed articles are best fitted with a log-normal regression model. This model allows the number of accesses an article receives and the time since it first becomes available in PubMed to be related via quadratic and logistic functions, with the model parameters to be estimated via maximum likelihood. Our experiments predicting the number of accesses for an article based on its past usage demonstrate that the mean absolute error and mean absolute percentage error of our model are 4.0% and 8.1% lower than the power-law regression model, respectively. The log-normal distribution is also shown to perform significantly better than a previous prediction method based on a human memory theory in cognitive science. This work warrants further investigation on the utility of such a log-normal regression approach towards improving information access in PubMed.