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(21 - 39 of 39)
Pages
- Title
- The rising sun stove polish.
- Date Created
- 1885-1895
- Identifier
- DP0015355
- Format
- E-book
- PURL
- http://purl.flvc.org/ucf/fd/DP0015355
- Title
- Ole Virginia Hickory Chips.
- Date Created
- 1940s
- Identifier
- DP0015371
- Format
- Set of related objects
- PURL
- http://purl.flvc.org/ucf/fd/DP0015371
- Title
- Old Black Joe speckled butter beans.
- Date Created
- 1940s
- Identifier
- DP0015349
- Format
- Image (JPEG)
- PURL
- http://purl.flvc.org/ucf/fd/DP0015349
- Title
- Sapolio.
- Date Created
- 1882
- Identifier
- DP0015446
- Format
- Set of related objects
- PURL
- http://purl.flvc.org/ucf/fd/DP0015446
- Title
- Smith & Buckley.
- Date Created
- 1879
- Identifier
- DP0015441
- Format
- Image (JPEG)
- PURL
- http://purl.flvc.org/ucf/fd/DP0015441
- Title
- Dixieland brand christian and cockrill.
- Date Created
- 1940s
- Identifier
- DP0015353
- Format
- Image (JPEG)
- PURL
- http://purl.flvc.org/ucf/fd/DP0015353
- Title
- Does yer Cotch on?.
- Date Created
- 1888
- Identifier
- DP0015367
- Format
- Set of related objects
- PURL
- http://purl.flvc.org/ucf/fd/DP0015367
- Title
- MODELING, DESIGN AND EVALUATION OF NETWORKING SYSTEMS AND PROTOCOLS THROUGH SIMULATION.
- Creator
-
Lacks, Daniel, Kocak, Taskin, University of Central Florida
- Abstract / Description
-
Computer modeling and simulation is a practical way to design and test a system without actually having to build it. Simulation has many benefits which apply to many different domains: it reduces costs creating different prototypes for mechanical engineers, increases the safety of chemical engineers exposed to dangerous chemicals, speeds up the time to model physical reactions, and trains soldiers to prepare for battle. The motivation behind this work is to build a common software framework...
Show moreComputer modeling and simulation is a practical way to design and test a system without actually having to build it. Simulation has many benefits which apply to many different domains: it reduces costs creating different prototypes for mechanical engineers, increases the safety of chemical engineers exposed to dangerous chemicals, speeds up the time to model physical reactions, and trains soldiers to prepare for battle. The motivation behind this work is to build a common software framework that can be used to create new networking simulators on top of an HLA-based federation for distributed simulation. The goals are to model and simulate networking architectures and protocols by developing a common underlying simulation infrastructure and to reduce the time a developer has to learn the semantics of message passing and time management to free more time for experimentation and data collection and reporting. This is accomplished by evolving the simulation engine through three different applications that model three different types of network protocols. Computer networking is a good candidate for simulation because of the Internet's rapid growth that has spawned off the need for new protocols and algorithms and the desire for a common infrastructure to model these protocols and algorithms. One simulation, the 3DInterconnect simulator, simulates data transmitting through a hardware k-array n-cube network interconnect. Performance results show that k-array n-cube topologies can sustain higher traffic load than the currently used interconnects. The second simulator, Cluster Leader Logic Algorithm Simulator, simulates an ad-hoc wireless routing protocol that uses a data distribution methodology based on the GPS-QHRA routing protocol. CLL algorithm can realize a maximum of 45% power savings and maximum 25% reduced queuing delay compared to GPS-QHRA. The third simulator simulates a grid resource discovery protocol for helping Virtual Organizations to find resource on a grid network to compute or store data on. Results show that worst-case 99.43% of the discovery messages are able to find a resource provider to use for computation. The simulation engine was then built to perform basic HLA operations. Results show successful HLA functions including creating, joining, and resigning from a federation, time management, and event publication and subscription.
Show less - Date Issued
- 2007
- Identifier
- CFE0001887, ucf:47399
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001887
- Title
- AN INTERACTIVE DISTRIBUTED SIMULATION FRAMEWORK WITH APPLICATION TO WIRELESS NETWORKS AND INTRUSION DETECTION.
- Creator
-
Kachirski, Oleg, Guha, Ratan, University of Central Florida
- Abstract / Description
-
In this dissertation, we describe the portable, open-source distributed simulation framework (WINDS) targeting simulations of wireless network infrastructures that we have developed. We present the simulation framework which uses modular architecture and apply the framework to studies of mobility pattern effects, routing and intrusion detection mechanisms in simulations of large-scale wireless ad hoc, infrastructure, and totally mobile networks. The distributed simulations within the...
Show moreIn this dissertation, we describe the portable, open-source distributed simulation framework (WINDS) targeting simulations of wireless network infrastructures that we have developed. We present the simulation framework which uses modular architecture and apply the framework to studies of mobility pattern effects, routing and intrusion detection mechanisms in simulations of large-scale wireless ad hoc, infrastructure, and totally mobile networks. The distributed simulations within the framework execute seamlessly and transparently to the user on a symmetric multiprocessor cluster computer or a network of computers with no modifications to the code or user objects. A visual graphical interface precisely depicts simulation object states and interactions throughout the simulation execution, giving the user full control over the simulation in real time. The network configuration is detected by the framework, and communication latency is taken into consideration when dynamically adjusting the simulation clock, allowing the simulation to run on a heterogeneous computing system. The simulation framework is easily extensible to multi-cluster systems and computing grids. An entire simulation system can be constructed in a short time, utilizing user-created and supplied simulation components, including mobile nodes, base stations, routing algorithms, traffic patterns and other objects. These objects are automatically compiled and loaded by the simulation system, and are available for dynamic simulation injection at runtime. Using our distributed simulation framework, we have studied modern intrusion detection systems (IDS) and assessed applicability of existing intrusion detection techniques to wireless networks. We have developed a mobile agent-based IDS targeting mobile wireless networks, and introduced load-balancing optimizations aimed at limited-resource systems to improve intrusion detection performance. Packet-based monitoring agents of our IDS employ a CASE-based reasoner engine that performs fast lookups of network packets in the existing SNORT-based intrusion rule-set. Experiments were performed using the intrusion data from MIT Lincoln Laboratories studies, and executed on a cluster computer utilizing our distributed simulation system.
Show less - Date Issued
- 2005
- Identifier
- CFE0000642, ucf:46545
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000642
- Title
- Health Literacy Intervention to Influence Choices Made by Students in a Title I School Who Receive Free Lunch.
- Creator
-
Kent, Melissa, Levin, Judith, Quelly, Susan, Szente, Judit, University of Central Florida
- Abstract / Description
-
This study seeks to influence choices made by Kindergarten students in a Title I school who receive free breakfast and lunch through a health literacy intervention with the intent of decreasing daily added sugar consumption. Fruit and milk choices, either with naturally occurring sugar (NOS) or added sugar (AS), were recorded for 70 Kindergarten students among six classes in a Title I school for ten days before a four-week health literacy intervention. Three of the classes were randomly...
Show moreThis study seeks to influence choices made by Kindergarten students in a Title I school who receive free breakfast and lunch through a health literacy intervention with the intent of decreasing daily added sugar consumption. Fruit and milk choices, either with naturally occurring sugar (NOS) or added sugar (AS), were recorded for 70 Kindergarten students among six classes in a Title I school for ten days before a four-week health literacy intervention. Three of the classes were randomly selected to learn about 'sometimes' and 'anytime' choices through the Healthy Habits for Life curriculum delivered by representatives from Nemours Children's Hospital. Following the intervention, milk and fruit choices were recorded for ten more school days to determine differences among the control and intervention groups. Pearson Chi Square test results concluded that the health literacy intervention lead to statistically significant improvements in milk choices for the intervention group, but fruit choices were inconclusive due to inconsistencies in significance. Hierarchical loglinear analyses were run to determine if there was a difference in response to intervention between male and female students, and the results indicated that the effectiveness of the intervention was not moderated by gender. The success of this intervention for milk choices will help students who receive free school breakfast and lunch to decrease their daily consumption of added sugars, and additional research needs to be done to help students make choices that will further decrease their daily added sugar consumption.
Show less - Date Issued
- 2019
- Identifier
- CFE0007662, ucf:52466
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007662
- Title
- Virtual Router Approach for Wireless Ad Hoc Networks.
- Creator
-
Ho, Ai, Hua, Kien, Guha, Ratan, Moshell, Jack, Zou, Changchun, Wang, Ching, University of Central Florida
- Abstract / Description
-
Wireless networks have become increasingly popular in recent years. There are two variations of mobile wireless networks: infrastructure mobile networks and infrastructureless mobile networks. The latter are also known as mobile ad hoc network (MANET). MANETs have no fixed routers. Instead, mobile nodes function as relay nodes or routers, which discover and maintain communication connections between source nodes and destination nodes for various data transmission sessions. In other words, an...
Show moreWireless networks have become increasingly popular in recent years. There are two variations of mobile wireless networks: infrastructure mobile networks and infrastructureless mobile networks. The latter are also known as mobile ad hoc network (MANET). MANETs have no fixed routers. Instead, mobile nodes function as relay nodes or routers, which discover and maintain communication connections between source nodes and destination nodes for various data transmission sessions. In other words, an MANET is a self-organizing multi-hop wireless network in which all nodes within a given geographical area participate in the routing and data forwarding process. Such networks are scalable and self-healing. They support mobile applications where an infrastructure is either not available (e.g., rescue operations and underground networks) or not desirable (e.g., harsh industrial environments).In many ad hoc networks such as vehicular networks, links among nodes change constantly and rapidly due to high node speed. Maintaining communication links of an established communication path that extends between source and destination nodes is a significant challenge in mobile ad hoc networks due to movement of the mobile nodes. In particular, such communication links are often broken under a high mobility environment. Communication links can also be broken by obstacles such as buildings in a street environment that block radio signal. In a street environment, obstacles and fast moving nodes result in a very short window of communication between nodes on different streets. Although a new communication route can be established when a break in the communication path occurs, repeatedly reestablishing new routes incurs delay and substantial overhead. To address this limitation, we introduce the Virtual Router abstraction in this dissertation. A virtual router is a dynamically-created logical router that is associated with a particular geographical area. Its routing functionality is provided by the physical nodes (i.e., mobile devices) currently within the geographical region served by the virtual router. These physical nodes take turns in forwarding data packets for the virtual router. In this environment, data packets are transmitted from a source node to a destination node over a series of virtual routers. Since virtual routers do not move, this scheme is much less susceptible to node mobility. There can be two virtual router approaches: Static Virtual Router (SVR) and Dynamic Virtual Router (DVR). In SVR, the virtual routers are predetermined and shared by all communication sessions over time. This scheme requires each mobile node to have a map of the virtual routers, and use a global positioning system (GPS) to determine if the node is within the geographical region of a given router. DVR is different from SVR with the following distinctions: (1) virtual routers are dynamically created for each communication sessions as needed, and deprecated after their use; (2) mobile nodes do not need to have a GPS; and (3) mobile nodes do not need to know whereabouts of the virtual routers.In this dissertation, we apply Virtual Router approach to address mobility challenges in routing data. We first propose a data routing protocol that uses SVR to overcome the extreme fast topology change in a street environment. We then propose a routing protocol that does not require node locations by adapting a DVR approach. We also explore how the Virtual Router Approach can reduce the overhead associated with initial route or location requests used by many existing routing protocols to find a destination. An initial request for a destination is expensive because all the nodes need to be reached to locate the destination. We propose two broadcast protocols; one in an open terrain environment and the other in a street environment. Both broadcast protocols apply SVR. We provide simulation results to demonstrate the effectiveness of the proposed protocols in handling high mobility. They show Virtual Router approach can achieve several times better performance than traditional routing and broadcast approach based on physical routers (i.e., relay nodes).
Show less - Date Issued
- 2011
- Identifier
- CFE0004119, ucf:49090
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004119
- Title
- An Investigation of Low Performing Central Florida Teacher Evaluation Feedback and Improvement Plans as Related to Value-Added Model Scores and Instructional Practice Scores.
- Creator
-
Butler, Tara, Murray, Barbara, Doherty, Walter, Murray, Kenneth, Baldwin, Lee, Hutchinson, Cynthia, University of Central Florida
- Abstract / Description
-
The purpose of this study was to determine if low performing Central Florida teachers, according to Florida VAM scores, had related instructional practice evaluations that were being used to determine placement on improvement plans in the 2013-14 school year. Additionally, the feedback held within the instructional practice evaluations was analyzed to discover the levels of feedback most frequently rendered by administrative evaluators to the lowest performing teachers. Deidentified data from...
Show moreThe purpose of this study was to determine if low performing Central Florida teachers, according to Florida VAM scores, had related instructional practice evaluations that were being used to determine placement on improvement plans in the 2013-14 school year. Additionally, the feedback held within the instructional practice evaluations was analyzed to discover the levels of feedback most frequently rendered by administrative evaluators to the lowest performing teachers. Deidentified data from a population of 528 Central Florida teacher evaluations and improvement plans within the lowest 10% of VAM scores for the 2013-14 school year were gathered from a Florida Department of Education database and public record requests. Data were analyzed to determine if any significant relationship existed between VAM scores and instructional practice scores. A very weak relationship existed between these two variables. Tenured teachers were rated significantly more favorably on summative instructional practice evaluations than nontenured teachers. Within the population, fewer than 1% of low-performing teachers (two total) were prescribed an improvement plan, regardless of tenure or nontenure status. Finally, evaluation feedback was largely low-level without reference to student growth or achievement. Evidence of administrative barriers within the three dimensions of individual conflict avoidance, bureaucratic procedural interferences, and administrative procedural faults were inferred from the literature and subsequent findings. To improve upon the current evaluation system, administrators must be aware of, and well-prepared for the demands of evaluating, remediating, and providing feedback to teaching professionals relative to student achievement and growth in a manner that is simultaneously respectful, candid, fair, timely, and actionable.
Show less - Date Issued
- 2017
- Identifier
- CFE0006937, ucf:51677
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006937
- Title
- Max Stadler & Co., Leading Clothiers.
- Date Created
- 1884
- Identifier
- DP0015447
- Format
- Set of related objects
- PURL
- http://purl.flvc.org/ucf/fd/DP0015447
- Title
- Topsy's matchbook.
- Date Created
- 1930s-1950s
- Identifier
- DP0015369
- Format
- Set of related objects
- PURL
- http://purl.flvc.org/ucf/fd/DP0015369
- Title
- We never fade!!.
- Date Created
- 1880s
- Identifier
- DP0015443
- Format
- Set of related objects
- PURL
- http://purl.flvc.org/ucf/fd/DP0015443
- Title
- Sapolio, Enoch Morgan & Sons.
- Date Created
- 1880s
- Identifier
- DP0015445
- Format
- E-book
- PURL
- http://purl.flvc.org/ucf/fd/DP0015445
- Title
- Seal of North Carolina: Smoking Tobacco Marburg Bros.
- Date Created
- 1840-1880
- Identifier
- DP0015390
- Format
- Set of related objects
- PURL
- http://purl.flvc.org/ucf/fd/DP0015390
- Title
- Scalable Map Information Dissemination for Connected and Automated Vehicle Systems.
- Creator
-
Gani, S M Osman, Pourmohammadi Fallah, Yaser, Vosoughi, Azadeh, Yuksel, Murat, Chatterjee, Mainak, Hasan, Samiul, University of Central Florida
- Abstract / Description
-
Situational awareness in connected and automated vehicle (CAV) systems becomes particularly challenging in the presence of non-line of sight objects and/or objects beyond the sensing range of local onboard sensors. Despite the fact that fully autonomous driving requires the use of multiple redundant sensor systems, primarily including camera, radar, and LiDAR, the non-line of sight object detection problem still persists due to the inherent limitations of those sensing techniques. To tackle...
Show moreSituational awareness in connected and automated vehicle (CAV) systems becomes particularly challenging in the presence of non-line of sight objects and/or objects beyond the sensing range of local onboard sensors. Despite the fact that fully autonomous driving requires the use of multiple redundant sensor systems, primarily including camera, radar, and LiDAR, the non-line of sight object detection problem still persists due to the inherent limitations of those sensing techniques. To tackle this challenge, the inter-vehicle communication system is envisioned that allows vehicles to exchange self-status updates aiming to extend their effective field of view and thus compensate for the limitations of the vehicle tracking subsystem that relies substantially on onboard sensing devices. Tracking capability in such systems can be further improved through the cooperative sharing of locally created map data instead of transmitting only self-update messages containing core basic safety message (BSM) data. In the cooperative sharing of safety messages, it is imperative to have a scalable communication protocol to ensure optimal use of the communication channel. This dissertation contributes to the analysis of the scalability issue in vehicle-to-everything (V2X) communication and then addresses the range issue of situational awareness in CAV systems by proposing a content-adaptive V2X communication architecture. To that end, we first analyze the BSM scheduling protocol standardized in the SAE J2945/1 and present large-scale scalability results obtained from a high-fidelity simulation platform to demonstrate the protocol's efficacy to address the scalability issues in V2X communication. By employing a distributed opportunistic approach, the SAE J2945/1 congestion control algorithm keeps the overall offered channel load within an optimal operating range, while meeting the minimum tracking requirements set forth by upper-layer applications. This scheduling protocol allows event-triggered and vehicle-dynamics driven message transmits that further the situational awareness in a cooperative V2X context. Presented validation results of the congestion control algorithm include position tracking errors as the performance measure, with the age of communicated information as the evaluation measure. In addition, we examine the optimality of the default settings of the congestion control parameters. Comprehensive analysis and trade-off study of the control parameters reveal some areas of improvement to further the algorithm's efficacy. Motivated by the effectiveness of channel congestion control mechanism, we further investigate message content and length adaptations, together with transmit rate control. Reasonably, the content of the exchanged information has a significant impact on the map accuracy in cooperative driving systems. We investigate different content control schemes for a communication architecture aimed at map sharing and evaluate their performance in terms of position tracking error. This dissertation determines that message content should be concentrated to mapped objects that are located farther away from the sender to the edge of the local sensor range. This dissertation also finds that optimized combination of message length and transmit rate ensures the optimal channel utilization for cooperative vehicular communication, which in turn improves the situational awareness of the whole system.
Show less - Date Issued
- 2019
- Identifier
- CFE0007634, ucf:52470
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007634
- Title
- Runge & Schacht.
- Date Created
- 1850
- Identifier
- DP0012815
- Format
- Set of related objects
- PURL
- http://purl.flvc.org/ucf/fd/DP0012815
