Packet Filtering in Computer Networks

Tato bakalářská práce se zabývá problematikou klasifikace paketů v počítačových sítích. V úvodu jsou popsány některé oblasti využívající klasifikaci paketů. Dále je uvedena potřebná teorie spolu s požadavky na klasifikační algoritmus. Jsou popsány čtyři vysokoúrovňové přístupy ke klasifikaci paketů. Ke každému přístupu jsou popsány principy několika algoritmů. Pro detailnější rozbor a implementaci je vybrán algoritmus EffiCuts. Tento klasifikační algoritmus je porovnán s jinými klasifikačními algoritmy z knihovny NetBench.This bachelor’s thesis deals with packet classification in computer networks. In the introduction it describes some areas where packet classification is used. Then, necessary theoretical background is introduced, together with requirements for classification algorithm. It describes four high-level approaches to the packet classification. It describes principle of various algorithms for each high-level approach. Algorithm EffiCuts is chosen for detailed analysis and implementation. This packet classification algorithm is compared with other packet classification algorithms from NetBench library.

Flow control for road vehicle drag reduction

This thesis covers topics that span bluff-body aerodynamics, hybrid RANS-LES CFD methods, flow control and model-order reduction. These topics arise from investigating the flow past three geometries: the bullet shaped D-body, the canonical squareback Ahmed body and the commerical Nissan NDP. The study on the D-body was aimed at transitioning the research group from the restrictive block-structured formulated StreamLES solver to the more flexible OpenFOAM code that can use unstructured meshes. Linear feedback control for base pressure increase was applied as was done in the work by Dalla Longa et al. (2017). Identification of the plant, G(s), that represents the wake's response to forcing was completed and correlated well with the results from Dalla Longa et al. (2017). The same can also be said of the sensitivity based designed feedback control law, K(s). When applied in simulation, an attenuation of the base pressure fluctuations was, as desired, achieved, although the base pressure increased by 24.5% as opposed to the 38% achieved by Dalla Longa et al. (2017). In the study on the squareback Ahmed body, wall-resolving (WRLES) and wall-modelled (WMLES) large eddy simulation were successfully applied. First, a simulation setup that is both able to resolve wake bimodality, while remaining reasonable in computational resource use, was created. Subsequently, variants of this setup were used to identify a flow feature that plays a critical role in forcing wake bimodality events. More specifically, a heavily under-resolved WMLES simulation in which both the near-wall and part of the outer-region of the turbulent boundary layer are Reynolds-averaged did not capture the front recirculation bubble near the Ahmed body nose; neither did it resolve a bimodal wake switching event. Meanwhile, the simulations with a more refined near-wall mesh did capture the front separation bubble as well as bimodal switching events of the wake. This front separation bubble sends out powerful hairpin vortices that interact with the rear wake. Specifically, these vortices go on to produce significant amounts of TKE, which, upon convection to the rear of the Ahmed body, ultimately help trigger a bimodal event. The Ahmed body study also involved the application of linear feedback control for drag reduction as was done in the D-body study. In the short term, mean blowing did lead to a base pressure increase, but as the zero-net-mass-flux (ZNMF) jet settled, it oscillated around zero making its effects indiscernible. The final geometry analyzed was the Nissan NDP. This was done by performing benchmark wall-resolving LES (WRLES). First, the benefit of appending a rear cavity to an otherwise "squareback" geometry was assessed. It was concluded that the cavity allows the wake to move more freely about the rear base. Specifically, the wake is freed from its more restricted motion that is present with the "squareback" Nissan NDP. In doing so, the drag reduction achieved with the cavity appendage is about 13.6%. Work on the Nissan NDP also involved an assessment of a moving ground in the simulation. It was concluded that, in the stationary ground simulation, flow detachment at the ground where the flow exits from the underbody has an adverse drag effect. In other words, although moving ground simulations better replicate the real-world conditions, the stationary ground variant is in this case more conservative, as it returns slightly higher drag values.Open Acces

Towards a Semantic-based Approach for Modeling Regulatory Documents in Building Industry

Regulations in the Building Industry are becoming increasingly complex and involve more than one technical area. They cover products, components and project implementation. They also play an important role to ensure the quality of a building, and to minimize its environmental impact. In this paper, we are particularly interested in the modeling of the regulatory constraints derived from the Technical Guides issued by CSTB and used to validate Technical Assessments. We first describe our approach for modeling regulatory constraints in the SBVR language, and formalizing them in the SPARQL language. Second, we describe how we model the processes of compliance checking described in the CSTB Technical Guides. Third, we show how we implement these processes to assist industrials in drafting Technical Documents in order to acquire a Technical Assessment; a compliance report is automatically generated to explain the compliance or noncompliance of this Technical Documents

Karen Bass in a Senior Voice Recital

This is the program for the senior voice recital of mezzo-soprano Karen Bass. Pianist Faron Wilson accompanied the performance. The recital took place in the Mabee Fine Arts Center Recital Hall on November 9, 1987

ONLINE GAMING BAHAVIOR AMONG JUNIOR HIGH SCHOOL STUDENTS: THE ROLE OF PARENTAL CONTROL, FEAR OF MISSING OUT (FOMO), AND SELF-CONTROL

This fast-paced digitalization era has made online gaming as one of internet content that often accessed by adolescent. This study aims to analyze the influence of parental control, FOMO, and self-control towards adolescents’ online gaming behavior. For about 200 of 7th grade students from one of selected junior high school in Banyumas Regency were participated in this study. The location and sample of this study were chosen using purposive sampling technique by criteria students aged 12-14years and come from intact family. Data were collected by self-report through filling out a questionnaire. Majority of adolescents had parental control practice and self-control in moderate level, while FOMO and  online gaming behavior were categorized in low level. Boys and girls were reported to have significant difference of self-control and online gaming behavior. Boys were discovered to have a higher level of self-control and online gaming behavior than girls. It also discovered that parental control and FOMO significantly influence the level of self-control. This self-control finally influences the level of adolescent’s online gaming behavior. Parents should understand how important their role is to prevent online gaming addiction among adolescents

Amanda Allen and Faron Wilson in a Joint Junior Recital

This is the program for the joint junior recital of soprano Amanda S. Allen and pianist Faron Wilson. The recital took place on February 26, 1988, in the Mabee Fine Arts Center Recital Hall