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

Faron Wilson in a Senior Piano Recital

This is the program for the senior piano recital of Faron Wilson. The recital took place on November 20, 1980, in the Mabee Fine Arts Center Recital Hall

Using Skills Profiling to Enable Badges and Micro-Credentials to be Incorporated into Higher Education Courses

Employers are increasingly selecting and developing employees based on skills rather than qualifications. Governments now have a growing focus on skilling, reskilling and upskilling the workforce through skills-based development rather than qualifications as a way of improving productivity. Both these changes are leading to a much stronger interest in digital badging and micro-credentialing that enables a more granular, skills-based development of learner-earners. This paper explores the use of an online skills profiling tool that can be used by designers, educators, researchers, employers and governments to understand how badges and micro-credentials can be incorporated within existing qualifications and how skills developed within learning can be compared and aligned to those sought in job roles. This work, and lessons learnt from the case study examples of computing-related degree programmes in the UK, also highlight exciting opportunities for educational providers to develop and accommodate personalised learning into existing formal education structures across a range of settings and contexts

Objectivity and Intellectual Humility in Scientific Research: They’re Harder Than You Think

We begin from the assumption that where scientific research will predictably be used to affect things of moral significance in the world, you have a special duty, a duty of care, to ‘get it right’. This, we argue, requires a special kind of objectivity, ‘objectivity to be found’. What is it that’s to be found? In any kind of scientific endeavour, you should make all reasonable efforts to find the right methods to get the right results to serve the purposes at stake and neither exaggerate nor underestimate the credibility of what you have done. That, we take it, is what in this context constitutes objectivity and intellectual humility. But where your results will affect the world, you have a more demanding duty: a duty to ‘get it right’ about the purposes the endeavour should serve. Often the most morally significant purposes are those that ‘go without saying’ and because they are not said, we can too easily overlook them, sometimes at the cost even of human lives. We illustrate this with the example of the Vajont dam design and the flawed modelling that resulted in the Hillsborough football disaster

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

Pencegahan Kecanduan Game Online pada Remaja melalui Optimalisasi Peran dan Fungsi Keluarga

Salah satu konten internet yang sering diakses oleh remaja adalah game online. Walaupun remaja menggunakan game online sebagai salah satu sarana hiburan, namun pengawasan orang tua masih diperlukan dalam penggunaanya. Terdapat beberapa faktor yang berpengaruh terhadap pembentukan perilaku bermain game online, yaitu kontrol orang tua, Fear of Missing Out (FOMO), dan kontrol diri. Perilaku bermain game online dipengaruhi secara langsung oleh kontrol orang tua dan kontrol diri remaja. Sementara itu, FOMO berpengaruh secara tidak langsung terhadap perilaku bermain game online melalui kontrol diri. Sebagai lingkungan yang paling dekat dengan anak, keluarga memiliki peran besar dalam pembentukan perilaku anak. Maka dari itu, penting untuk mengoptimalisasi peran dan fungsi keluarga sebagai salah satu langkah dalam pencegahan kecanduan game online remaja