In this dissertation, the seismic behavior and design of AAC-infilled steel moment frames are investigated systematically. The fundamental vehicle for this investigation is the ATC-63 methodology, which is intended for the establishment of seismic design factors for structural systems. The ATC-63 methodology is briefly reviewed, including the concepts of archetypical structures, design rules and mathematical models simulating the behavior of those archetypes. A limited experimental investigation on the hysteretic behavior of an AAC-infilled steel moment frame is developed, conducted, and discussed. Using the experimental results of that investigation, the draft infill design provisions of the Masonry Standards Joint Committee (MSJC) are extended to AAC infills, and a mathematical model is developed and calibrated to simulate the behavior of AAC infills under reversed cyclic loads. Prior to application of ATC-63 methodology to AAC-infilled steel moment frames, the methodology is applied to an example steel moment frame to demonstrate the methodology and verify understanding of it. Then, archetypical infilled frames to be evaluated by the ATC-63 methodology are developed using a series of pushover analyses. Infill configurations whose total lateral strength in a particular story exceeds about 35% of the lateral strength of the bare frame in that story are observed to provoke story mechanisms in the frame. Based on this observation, archetypical infilled frames are selected conforming to two infill configurations: uniformly infilled frames, and open ground story frames. Each infill configuration includes archetypes whose ratio of infill strength to bare-frame strength at each story is less than 35%, and archetypes whose ratio is greater than 35%. The former archetype is typical of steel moment frames infilled with AAC; the latter archetype is typical of steel moment frames infilled with conventional (clay or concrete) masonry. The ATC-63 methodology, specialized for application to infilled frames, is applied to the archetypical infilled frames developed above. The performance of those archetypical infilled frames is evaluated, and seismic design factors are proposed for AAC-infilled steel moment frames. The extension of this work to other types of infilled frames is discussed. / text

Title: The Choice of Universal Abseiling Aids for the Requirements of the Czech Armed Forces Objectives: Choosing abseiling - belaying aids in accordance with the needs of the Czech Armed Forces. Methods: A mixed empirical research was involved. In order to analyse the results, closed questionnaires created in MS Excel were produced and evaluated later on. They were split into two phases. The analysis of the relationships of the variables was carried out using methods of descriptive statistics. To collect data, the Delphi research method was used. The survey was conducted in cooperation with chief instructors of military climbing. Respondents were selected according to their qualifications. Results: It was chosen ATC Guide like the most acceptable abseiling aid for the requirements of the Czech armed forces by informant with help research method Delphi. Keywords: Research method Delphi, Special physical education, Army climbing, Descent, ATC Guide. J. STRNAD 10.4. 2011

Abstract In this thesis, we use a high power 1550 nm DFB laser and a Ti:LiNbO3 Mach-Zehnder modulator to construct an externally modulated trensmitter for CATV lightwave system. We use two methods to reduce the problem caused by stimulated Brillouin scattering (SBS) effect in externally modulated AM video system by using high-frequency phase modulation and low-frequency dithering techniques. In this experiment, the SBS threshold can be increased by 6 dB. We also design a automatic gain control (AGC) circuit with a 10 dB dynamic range in our transmitter. After addition with a home-made predistortion linearized circuit, the system performance of this transmitter in a 20 km single-mode fiber link carrying 60 NTSC channels can be achieved with a CNR¡Ù46~52 dB¡BCSO¡Ø-68~-73 dBc¡BCTB¡Ø-59~-63 dBc. As the number of channels increased from 60 to 80, we can obtain CNR¡Ù46~51 dB, CSO¡Ø-65.5~-71 dBc, and CTB¡Ø-55~-60.4 dBc. According to preceding description, we know that our trensmitter can carry 60 ~ 80 NTSC channels.

Short Term Conflict Alert (STCA) is an automated warning system designed to alert air traffic controllers to possible loss of separation between aircraft. STCA systems are complex, with many parameters that must be adjusted to achieve best performance. Current procedure is to manually ‘tune’ the governing parameters in order to finely balance the trade-off between wanted alerts and nuisance alerts. We present an incremental approach to automatically optimising STCA systems, using a simple evolutionary algorithm. By dividing the parameter space into regional subsets, we investigate methods of reducing the number of evaluations required to generate the Pareto optimal Receiver Operating Characteristic (ROC) curve. Multi-archive techniques are devised and are shown to cut the necessary number of iterations by half. A method of estimating the fitness of recombined regional parameter subsets without actual evaluation on the STCA system is presented, however, convergence is shown to be severely stunted when relatively weak sources of noise are present. We describe a method of aggressively perturbing parameters outside of their known ‘safe’ ranges when complex inhibitory interactions are present that prevent an exhaustive search of permitted values. The scheme prevents the optimiser from repeating ‘mistakes’ and unnecessarily wasting evaluations. Results show that a more complete picture of the Pareto-optimal ROC curve may be obtained without increasing the number of necessary iterations. Efficacy of the new methods is discussed, with suggestions for improving efficiency. Sources of parameter interdependence and noise are explored and where possible mitigating techniques and procedures suggested. Classifier performance on training and test data is investigated and potential solutions for reducing overfitting are evaluated on a toy problem. We comment on potential uses of the ROC in characterising STCA performance, for comparison to other systems and airspaces. Many industrial systems are structured in a similar way to STCA, we hope that techniques presented will be applicable to other highly parametrised, expensive problem domains.

The abuse of dominant position by establishing predatory pricing raises when the undertaking, seeking to eliminate its competitor determines to sell goods for unreasonably low price, while after elimination or weakening of competition subsequently raises those prices in order to recoup losses and earn higher profits. In theory there is consensus that determination of such pricing must be based of two-tier tests, which are comprised of price-cost comparison and analysis of subjective intent. Such test has been determined in AKZO case and until recently is applicable in the EC and Lithuanian competition law. It states that the price below VKS is presumed to be predatory; in such case if the price is between VKS and VVS, it can be acknowledged to be predatory if it is used in order to eliminate the competitor. While evaluating this test, the paper discusses practical problems arising while applying VKS criterion and raises proposal to change it by more accurate VIS criterion. Moreover, paper raises the idea that dominant element in AKZO test is not economical elements, but subjective predatory intent. Therefore economical elements must be treated only as a tool, providing the possibility to disclose the content of subjective intent. While analyzing the rules for determination of predatory pricing, the paper also discusses the third criterion which settled in EC practice and maintains the possibility to determine predatory pricing even if the prices are above VVS. After critical... [to full text]

Den här rapporten är en utredning och analys av lämpliga arbetsuppgifter och deras nödvändiga verktyg och hjälpmedel för en skiftledare, Watch Supervisor, vid ett framtida center för fjärrstyrda flygledningstorn, Remote Tower. Ett center för fjärrstyrda flygledningstorn är en centraliserad enhet med uppgiften att flygleda och kontrollera flygsäkerheten på och nära en eller flera flygplatser. Utgångspunkten för datainsamlingen har varit intervjuer med verksamma flygledare och skiftledare på LFV, Sveriges statliga verk för flygtrafiktjänst. Studiebesök har även gjorts vid olika enheter, både flygledartorn och radarkontrollcentraler, däribland Sundsvall RTC som är världens första central för fjärrstyrd flygledning godkänd att sättas i drift. Insamlad data har kompilerats och analyserats och en rekommendation presenteras i slutet av denna rapport angående arbetsuppgifter och verktyg för ovan nämnda skiftledare i ett RTC. Resultatet visar att rollen kommer ha stora likheter med befintliga skiftledarpositioner i den svenska flygledningen.

In a time where general technology is progressing at a rapid rate, this thesis aims to present possible advancements to security in regard to air traffic communication. By highlighting how data can be extracted using simple hardware and open-source software the transparency and lack of authentication is showcased. The research is specifically narrowed down to discovering vulnerabilities of the ADS-B protocol in order to apply countermeasures. Through fetching live aircraft data with OpenSky-Network and through fetching simulated ADS-B attack data with OpenScope, this thesis develops a data set with both authentic and malicious ADS-B messages. The data set was cleaned in order to remove outliers and other improper data. A machine learning model was later trained with the data set in order to detect malicious ADS-B messages. With the use of Support Vector Machine (SVM), it was possible to produce a model that can detect four different types of aviation communications attacks as well as allow authentic messages to pass through the IDS. The finished model was able to detect incoming ADS-B attacks with an overall accuracy of 83.10%.

This dissertation thesis is focused on the problem of the Automatic Tool Change for milling centers, which is recently shown as a very current topic. The content of this work is to conduct a comprehensive research of various types of ATC depending on the type of machine, as well as research of the current tool interface relating closely with these problems. There was made a comprehensive analysis on the basis of data obtained by comprehensive research, from which both the main factors affecting this topic and the area dealed and developed by this work resulted. The most problematic area of machinery used nowdays for the Atomatic Tool Change was detected as manipulator provided the exchange between spindle and tool storage. Kinematic structure and design of individual elements affects very significantly the dynamics of the whole process of exchange of tools. Therefore, the work is focused on problematic of the manipulator. The main results of this thesis are constructional design of several types of manipulators, which were partly realized within the project 1.2.4 of Brno department of RCMT in the form of the testing stands. There was developed simulation models for selected types of manipulators which were verificated by measuring on the real stand. On the basis of abovementioned problem there was identified another key issue related not only to the exchange process but also with complex problem of service life of spindle. It is a grab force in the process of picking tools. The work outlines the possibilities for further research of these forces on the service file of spindle (especially on service life of bering groups of spindle).

The aviation industry is under increasing pressure to reduce cost and manage the increased number of passengers. One area under pressure is the Air Traffic Control. The Air Traffic Control will in a foreseeable future manage the introduction of drones also known as Unmanned Aerial Vehicles by integrating them into civil airspace with manned aircraft. Drones are lacking consensus from authorities with regards to standards due to their rapid expansion. Given their size, shape and speed, they can also pose threats to manned aircrafts and there is a need to address them in an Air Traffic Management system interoperating with manned aircrafts. The purpose in this study is to identify what considerations to make when automating complex system elements with respect to safety. Safety involves all the different stakeholders in the air transportation system, which is a Safety critical System. Furthermore, the aim is also to identify areas in which European Operational Concept Validation Methodology (E-OCVM) can be complemented with. Standard E-OCVM is missing specific assessment criteria with regards to safety and how it can interact with other standards. The approach is thereby to use various standards with focus on Systems Engineering to complement E-OCVM since it is lacking with regards to how it is used to validate Air Traffic Control systems. To capture the complexity of automating elements of an industry involving many stakeholders, a qualitative analysis was conducted in this project, using a System Engineering approach with four standards A-SLP, A-RLP, A-DAS and A-SAS. A-SLP and A-RLP are two general standards while A-DAS and A-SAS are focusing on the contexts of aircrafts and software development. Empirical data was gathered by semi-structured interviews of seven experts within the relevant areas in the field. From the review of the four standards, it was found that they can for instance complement E-OCVM in how software errors can lead to a failure condition among other ways. The main identified considerations faced with an integration of drones into civil airspace, is to manage the human interaction with the introduced Air Traffic Management systems. More specifically, the human element must be involved from the training phase in the development of systems in a Safety Critical System to minimize risk. Furthermore, redundancies that are built into the system has to, not only be able to put the system into a safe state, but also be carefully analyzed in how they interact with other systems to avoid misjudgement for the Air Traffic Controllers. Lastly, to obtain specific details on how interoperability could occur using standards, the standards used in this study refer to usage of other documents and standards. Standards specifically tailored for the operational context of drones would facilitate further testing and implementation of their integration into civil airspace. Given that different standards were used to complement the EOCVM standard, a set of unified standards are required that are proportional with the type of drones, the type of operations and in the environment that they are operating in. This will be needed to fulfill the European vision of safe integration of drones and needs thereby to be carried out in a global manner, thus also share experience with other actors to advance the new technology adaptation.

No description available.