An evaluation of Discover Nature Schools /

Fidelity of implementation (FOI) is the extent to which a program is implemented as designed. There needs to be more work on conceptualizing and measuring FOI in conservation education programs. There also needs to be a better understanding of how conservation education programs affect variables important to intended stewardship behaviors. I evaluated the Discover Nature Schools (DNS) program, a pre-K-12 conservation education curriculum developed by the Missouri Department of Conservation (MDC), using a case study approach that included teacher focus groups, an intensive classroom study, and a statewide teacher survey to answer the following research questions: What is the Fidelity of Implementation of the DNS program? How are variables important to intended stewardship behaviors affected by participation in the DNS program? How does Fidelity of Implementation influence variables important to intended stewardship? What variables predict Fidelity of Implementation of the DNS program? I found that DNS does a good job of teaching content, although there were mixed results for teaching scientific inquiry. Teaching students outside increased students' environmental sensitivity and self-assessed knowledge of behaviors to help wildlife, regardless of whether or not students were in the DNS or comparison classrooms. Teachers generally had positive things to say about the DNS program. Teachers had varying levels of implementation of DNS, with few teachers saying they taught DNS "by the book." Institutional barriers, alignment of DNS with academic standards, outside support, and challenges teaching lessons outdoors affected FOI. The amount of instructional time, teacher content knowledge, school district support, and support from MDC predicted FOI. The DNS program had some components of FOI, such as teaching outside, that were not included in the operationalization of FOI of general math and science curricula. I also found there is not a straightforward relationship between FOI and outcomes for the DNS program. For example, having more lessons outside was associated with increases in environmental sensitivity. However, FOI was not related to pre-/post-unit changes in ecological knowledge. I recommend further study, including refining how FOI is defined and measured, of FOI in environmental education programs.Dr. Charles Nilon, Dissertation Supervisor.|Includes vita.Includes bibliographical references

Drag Reduction by Polymers in Turbulent Channel Flows: Energy Redistribution Between Invariant Empirical Modes

We address the phenomenon of drag reduction by dilute polymeric additive to turbulent flows, using Direct Numerical Simulations (DNS) of the FENE-P model of viscoelastic flows. It had been amply demonstrated that these model equations reproduce the phenomenon, but the results of DNS were not analyzed so far with the goal of interpreting the phenomenon. In order to construct a useful framework for the understanding of drag reduction we initiate in this paper an investigation of the most important modes that are sustained in the viscoelastic and Newtonian turbulent flows respectively. The modes are obtained empirically using the Karhunen-Loeve decomposition, allowing us to compare the most energetic modes in the viscoelastic and Newtonian flows. The main finding of the present study is that the spatial profile of the most energetic modes is hardly changed between the two flows. What changes is the energy associated with these modes, and their relative ordering in the decreasing order from the most energetic to the least. Modes that are highly excited in one flow can be strongly suppressed in the other, and vice versa. This dramatic energy redistribution is an important clue to the mechanism of drag reduction as is proposed in this paper. In particular there is an enhancement of the energy containing modes in the viscoelastic flow compared to the Newtonian one; drag reduction is seen in the energy containing modes rather than the dissipative modes as proposed in some previous theories.Comment: 11 pages, 13 figures, included, PRE, submitted, REVTeX

Poster:Observable KINDNS: Validating DNS Hygiene

The Internet's naming system (DNS) is a hierarchically structured database, with hundreds of millions of domains in a radically distributed management architecture. The distributed nature of the DNS is the primary factor that allowed it to scale to its current size, but it also brings security and stability risks. The Internet standards community (IETF) has published several operational best practices to improve DNS resilience, but operators must make their own decisions that tradeoff security, cost, and complexity. Since these decisions can impact the security of billions of Internet users, recently ICANN has proposed an initiative to codify best practices into a set of global norms to improve security: the Knowledge-Sharing and Instantiating Norms for DNS and Naming Security (KINDNS) [4]. A similar effort for routing security - Mutually Agreed Norms for Routing Security - provided inspiration for this effort. The MANRS program encourages operators to voluntarily commit to a set of practices that will improve collective routing security - a challenge when incentives to conform with these practices does not generate a clear return on investment for operators. One challenge for both initiatives is independent verification of conformance with the practices. The KINDNS conversation has just started, and stakeholders are still debating what should be in the set of practices. At this early stage, we analyze possible best practices in terms of their measurability by third parties, including a review of DNS measurement studies and available data sets (Table 1)

Government mandated blocking of foreign Web content

Blocking of foreign Web content by Internet access providers has been a hot topic for the last 18 months in Germany. Since fall 2001 the state of North-Rhine-Westphalia very actively tries to mandate such blocking. This paper will take a technical view on the problems imposed by the blocking orders and blocking content at access or network provider level in general. It will also give some empirical data on the effects of the blocking orders to help in the legal assessment of the orders.Comment: Preprint, revised 30.6.200

Fingerprinting Internet DNS Amplification DDoS Activities

This work proposes a novel approach to infer and characterize Internet-scale DNS amplification DDoS attacks by leveraging the darknet space. Complementary to the pioneer work on inferring Distributed Denial of Service (DDoS) activities using darknet, this work shows that we can extract DDoS activities without relying on backscattered analysis. The aim of this work is to extract cyber security intelligence related to DNS Amplification DDoS activities such as detection period, attack duration, intensity, packet size, rate and geo-location in addition to various network-layer and flow-based insights. To achieve this task, the proposed approach exploits certain DDoS parameters to detect the attacks. We empirically evaluate the proposed approach using 720 GB of real darknet data collected from a /13 address space during a recent three months period. Our analysis reveals that the approach was successful in inferring significant DNS amplification DDoS activities including the recent prominent attack that targeted one of the largest anti-spam organizations. Moreover, the analysis disclosed the mechanism of such DNS amplification DDoS attacks. Further, the results uncover high-speed and stealthy attempts that were never previously documented. The case study of the largest DDoS attack in history lead to a better understanding of the nature and scale of this threat and can generate inferences that could contribute in detecting, preventing, assessing, mitigating and even attributing of DNS amplification DDoS activities.Comment: 5 pages, 2 figure

Securing The Root: A Proposal For Distributing Signing Authority

Management of the Domain Name System (DNS) root zone file is a uniquely global policy problem. For the Internet to connect everyone, the root must be coordinated and compatible. While authority over the legacy root zone file has been contentious and divisive at times, everyone agrees that the Internet should be made more secure. A newly standardized protocol, DNS Security Extensions (DNSSEC), would make the Internet's infrastructure more secure. In order to fully implement DNSSEC, the procedures for managing the DNS root must be revised. Therein lies an opportunity. In revising the root zone management procedures, we can develop a new solution that diminishes the impact of the legacy monopoly held by the U.S. government and avoids another contentious debate over unilateral U.S. control. In this paper we describe the outlines of a new system for the management of a DNSSEC-enabled root. Our proposal distributes authority over securing the root, unlike another recently suggested method, while avoiding the risks and pitfalls of an intergovernmental power sharing scheme