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In dieser Arbeit sollen die maßgeblichen nationalen Zugbeeinflussungssysteme der Länder Polen (SHP, Radio-Stop, KHP), Slowakei und Tschechien (LS, MIREL VZ1) vorgestellt und miteinander verglichen werden. Der Fokus liegt dabei auf einer funktionellen Betrachtung, wobei auch der technische Hintergrund nicht unberücksichtigt bleibt. Ein Ausblick auf die zukünftigen Bemühungen hinsichtlich ETCS rundet den Überblick ab. / This paper compares the major national train protection systems of Poland (SHP, Radio-Stop, KHP), the Slovak Republic and Czechia (LS, MIREL VZ1). The emphasis is placed on a functional description, while mentioning the relevant technical background where necessary. An outlook on future developments regarding ETCS in the respective countries concludes each chapter.

In order to prevent power system blackout, and enhance system reliability, various forms of special protection systems (SPS) and defense plans have been implemented by utilities around the world. One of the main concerns in the design of an SPS is to assure whether the system could fit with the reliability specification requirements. The failure of SPS to detect the defined conditions and carry out the required actions, or to take unnecessary actions, could lead to serious and costly consequences. Thus, a quantitative reliability assessment for SPS is important and necessary. Using a single point value for the parameter to evaluate the reliability of SPS might give incomplete information about the system reliability due to the uncertainty of reliability model and input data. When a review study suggests that some modifications of the existing scheme are necessary, the sensitivity analysis techniques could provide the tools to do this investigation to identify the most significant components that have essential effects on the reliability of the SPS. In this dissertation, by incorporating an interval theory, a risk reduction worth importance concept, and a probabilistic risk-based index, a procedure is proposed to conduct parameter uncertainty analysis, identify critical factors in the reliability model, perform probabilistic risk assessments (PRA) and determine a better option for the refinement of the studied SPS decision process logic module. One of the existing SPSs of Taipower systems is used to illustrate the practicability and appropriation of the proposed design refinement procedure. With the advent of deregulation in the power industry, utilities have experienced a great pressure to fully utilize their current facilities to the maximum level. SPSs are often considered as a cost effective way in achieving this goal. This dissertation also presents a framework for quantitative assessment of the benefits and risks due to SPS implementation. Changes in energy, spinning reserve and customer interruption costs resulting from SPS operations are evaluated and risks of SPS operations and system security are assessed. The proposed methodologies are useful for power system planners and operators to evaluate the value and effectiveness of SPS for the remedy of transmission congestion and reliability problems.

Lightning is a natural phenomenon involving transient high current discharge in the atmosphere. Cloud-to-ground lightning, wherein the discharge occurs between the cloud and the ground is quite hazardous to systems on the ground. Apart from threat to life, the devastating effects of lightning can be mainly of thermal, mechanical and electromagnetic origin. Many a times, thermal and electromagnetic effects are of main concern. A direct hit, wherein the system under consideration becomes a part of the lightning path, could be quite catastrophic to many vulnerable systems like oil rigs, chemical factories, missile/satellite launch pads. From the safety and operational point of view, lightning is of serious concern for electrical systems including transmission lines and substations, nuclear power stations, telecommunication station and data banks. Lightning cannot be avoided, however, by employing a suitable Lightning Protection System (LPS), adequate protection against a direct hit can be provided to ground based systems. A typical lightning protection system involves: 1) Air termination network, which is responsible for stroke interception, 2) Down conductor system, which provides to the stroke current a minimal impedance path to the ground and 3) Earth termination network, for safe dissipation of current into the ground. Similarly, for the indirect effects, which are basically of electromagnetic origin, suitable protection can be designed. The key factors in a protective action involve interception of the dangerous strokes, minimization of the consequential potential rise on down conductors, as well as, at earth termination and keeping the field in the protective volume within an acceptable level. The last aspect can be generally categorized into secondary level protection. For critical systems, the lightning protection system is generally isolated from it. In such designs, potential rise on LPS governs the physical isolation required between the protected and protection system. For a given level of bypass strokes, cost of the LPS increases with the amount of physical separation employed. All most all of the earlier works have concentrated on lightning surge response of power transmission line towers. Apart from their relatively moderate heights, the intention was to arrive at a model, which can be incorporated in circuit simulation software like EMTP. Consequently, they envisage or approximate the mode of propagation to be TEM. In reality, for down conductors of height greater than say 30 m, only TM mode prevails during the initial critical time period. Hence the earlier models cannot be extended to general lightning protection schemes and for down conductor of larger lengths. Only limited literature seems to be available on the characteristics of general down conductor configurations. The problem in hand is very important and some serious research efforts are very much essential. In view of the above, the present work aims to evaluate the rise in potential as well as current injected into the soil at the base for: (i) practical range of down conductor configurations involving single down conductor (with height exceeding 30 m) and (ii) pertinent values of stroke current parameters. The protection schemes considered are isolated vertical down conductor, isolated tower (both square and triangular cross-section) and, tower with insulated lightning mast carrying ground wires. The parameters under consideration are: (i) height and cross section for the down conductor, (ii) clearance between the down conductor and the protected system, (iii) channel geometry, wherein only inclination is to be considered, (iv) velocity of current along the channel and (v) wave shape and rise time for the stroke current. For the evaluation of lightning surge response of transmission line towers, many theoretical and experimental approaches are found in the literature. However, works considering the TM mode of current propagation is relatively limited. In that both experimental and theoretical approaches have been adopted. Theoretical approach invariably adopted numerical field computation in frequency domain using Numerical Electromagnetic code (NEC-2). Fourier Transform techniques are employed to extract the time domain quantities. This approach is very economical, free from experimental errors and least time consuming. Hence it is selected for the present work. However, there are certain limitations in this approach. In NEC simulation, there is a restriction on the size and the arrangement of individual elements. Therefore, although fairly complex tower structures can be simulated, some simplification in the geometry is unavoidable. Such an approximation has been reported to cause insignificant error. NEC is not accurate for calculations in low frequency regime. But in the present work, the initial time regime is of concern wherein the high frequency components dominate. Therefore the above said limitation is not of any serious concern. In order to validate the approach, potential rise is computed for 120 m tall cylindrical down conductor and tower. Results are compared favorably with earlier works, which are based on potential lead wire method. A careful re-look into the ’potential rise’ on the down conductors reveal several things. The electric field in the region between the protection system and protected system is the root cause for the breakdown/flashover. For a given geometry, the integral of the electric field along the shortest path between the two systems must be representing the overall stress on the air gap. Further, for the later time periods, this integral coincides with the well-known quasi-static potential. All the available data and models for breakdown of long air gaps are basically in terms of this quasi-static potential. In view of this, the above path integral is defined as ’equivalent potential rise’ (which will be hereafter termed as ’potential rise’), and taken as the index for surge response. Further, observation of the computed spatio-temporal radial electric field around the down conductor reveals some additional features, which are not common in the quasi-static regime. Electric field reverses its polarity in space, which is due to the opposite current flowing in the lightning channel. Therefore, ’potential rise’, which is taken as the representative for the dielectric stress on the air, should not be evaluated for larger distances. Considering this and noting that the protected system generally lies well within a distance of 50% of the H, height of the down conductor, potential rise is evaluated by integrating electric field within this distance (12.5%H, 25%H, 50%H). Three heights (100%H, 75%H, 50%H) are considered for the evaluation of the potential. The influences of various down conductor and lightning channel parameters are analyzed. Finally vertical channel with full velocity for current propagation is arrived for the investigations. Also, the influence of neighboring conducting objects is briefly studied. It is argued that it needs to be ignored for the general study. Analysis is carried out for a range of down conductor configurations of heights ranging from 45 m to 120 m. Cylindrical down conductor is selected for the detailed study on the overall characteristics and its dependency on pertinent parameters. The characteristics of potential rise are found to be significantly different from that given by the commonly employed uniform transmission line model. In the regime of very fast front currents, down conductor of comparable heights have comparable potential rise. For the larger time to crest, behavior tends more to wards that for quasi-static regime. The dependency of the potential rise on radius of the down conductor seems to be logarithmic in nature. Surge response of isolated towers of both square and triangular cross sections is studied for heights ranging from 45 m to 120 m. The overall characteristics are found to be similar to cylindrical down conductor. Dispersive propagation is found to exist on towers. As a result, the base currents are slightly lower and potential rise exhibits less oscillations. Data curves on potential rise at three different heights and for three different spatial extents are generated for the range of down conductor heights with rise time of the stroke current as the variable. Several interesting observations have been made. Next the investigation is taken up for the insulated mast scheme. The parameters of the study are taken as the number of ground wires, grounding location of ground wires and length of the insulation cylinder. Potential across the insulation, tower base currents, and ground wire end currents are deduced. The basic characteristics of the potential rise are shown to be quite similar to that for the transmission line. For fast front currents the temporal variation is bipolar with a smooth decay. In other words, oscillations are sustained for considerably longer duration. Voltage stress across the insulation surface for one ground wire design is found to be higher by 1.4 - 2.4 times than that for isolated tower. The highest amplification of the ground end current, which occurs for fast front currents, is about 1.8 times. Potential difference across the insulation for two-ground wire design is higher by a factor of 1.3 - 1.85 than that for isolated tower. For the design with four ground wires, potential across the insulation is comparable with that for the tower. However, the mechanical strength of the insulating support should also be considered in the selection of number of ground wires. There exists, especially for fast front strokes, significant induction to the supporting tower. The height of the insulation seems to possess no appreciable influence on the potential rise and base currents. Several issues need to be considered before selecting this design. The contribution made by the present work can be summarized as follows. It basically deals with lightning surge response of isolated down conductors of height in the range 45 - 120 m. The configurations considered are, cylindrical down conductor, tower with both square and triangular cross section and insulated mast scheme. It makes a careful study on the ’potential rise’ on down conductors and a suitable definition for the same is proposed. Basic characteristics of potential rise and ground end currents are studied for the above-mentioned designs. Their salient features are enumerated. For the towers, design data curves are provided for relevant range of stroke current rise time. The issues that need to be considered in the insulated mast scheme are discussed along with the data on potential rise and base currents. The findings of this work are believed to be very useful for the design of lightning protection scheme involving isolated down conductor. Further the results are useful in analyzing the consequential lightning generated threat of being close to tall towers.

Satellites have become absolute necessity in the growing modern space technology. At present, launch pads are the only means for launching of satellites or any other space vehicles. Due to the large magnitude of current and the associated rate of rise, a lightning strike to launch pads can be quite disastrous. Satellite launch complex forms typically the tallest object in that region. This makes them the more vulnerable to cloud-to-ground lightning. In addition, most of the launch pads are situated near the coastal area, where the isokeraunic levels are quite high. In view of these, almost all the satellite launch pads are provided with suitable Lightning Protection Systems (LPS). The LPS is basically intended for protecting against a direct lightning hit. The present work is related with the LPS to Indian satellite launch pads, Pad-I and Pad-II. The protection system for Pad-I consists of three 120 m tall towers placed approximately at the vertices of an equilateral triangle of 180 m. The same for Pad-II consist of 120 m tall towers placed at vertices of rectangle of size 90 m x 105 m. Towers are interconnected by 6 shield wires at the top. A mast of 10m length forms the top of the tower. Significant work on the analysis of interception efficacy of these protection systems has been reported in the literature. The lightning surge response of these systems have also been analysed and reported. The interception efficacy of these LPS in field can be ascertained by pertinent measurements. Measuring the lightning current on LPS seems to be one of the most suitable choices for this purpose. It would also greatly facilitate collection of local lightning current statistics, data on which is almost absent. Several considerations suggest that the tower bases form ideal place for such measurement. However, such lightning current records would involve mainly the current resulting from stroke interception, as well as, induced current due to strokes nearby. Literature on categorisation of measured currents to the type of stroke and correlation of measured currents to the incident stroke currents is rather limited. This is especially true for interconnected protection system of the type dealt in the present work. Considering these the present work is taken up and its scope is defined as: (i) Evolve a suitable model for study of current distribution in LPS due to Lightning and using the same deduce the current due to stroke interception and that due to stroke nearby. (ii) For the purpose of categorization identify the salient characteristics of current due to the intercepted strokes and that due to bypass/nearby strokes (iii) For the intercepted strokes, develop a processor for estimating the injected stroke current from the measured tower base currents. Lightning event, apart from other associated physical phenomena, is strongly governed by electromagnetic fields. Any method employed for the analysis, either theoretical or experimental, should satisfy the governing electromagnetic equations. As experimentation on actual system, as well as, their laboratory simulation is nearly impossible, theoretical modelling approach is selected. Modelling involves modelling of the channel along with its excitation, modelling of the LPS and modelling of the ground. Channel, following the literature, is represented as a loaded conductor with a lumped current source at the junction point. Such models have quite successfully predicted the electromagnetic fields and current in other places on the down conductor. For the LPS, some simplifications on the geometry are very essential. Tower lattice elements of dimensions much smaller than the wavelength of highest dominant frequency component of lightning current spectrum are neglected. Suitable modification is made for the tower top involving a plate and interconnection of several short members. For the close range within 200 – 400 m, even for the induced currents, the influence of ground in the literature has been reported to be small. Also, there is an extensive grounding network in these systems. In view of the same, a perfectly conducting ground along with suitable ground termination impedance is considered. Only the numerical solution of the problem is feasible and for the same, following the literature, NEC-2 is employed. All the guidelines of NEC are respected in the discretisation. Geometric mean radius is employed for modelling the complex tower elements. Fourier Transform Techniques are employed for time domain conversion of the computed frequency domain quantities. Occasionally, numerical inversion error of magnitude less than 5% is encountered. For the validation of the numerical modelling for both direct stroke and that nearby, time domain experimentation on electromagnetically reduced scale models (35:1) is employed. As the channel electrical and geometrical parameters are stochastic in nature, it is necessary to ensure that the deduction made using the model is practically relevant. For this, some parametric studies are conducted. The influence of channel length and inclination, stroke current velocity etc. has been shown to be insignificant for the case of intercepted strokes. Simulations are carried out for the stroke intercepted (i.e. direct strikes) by the LPS. The characteristics of the tower base currents are investigated. The base currents indicate a dispersive propagation along the towers and further a frequency dependent current division at the tower-shield wire junctions. Base currents contain superimposed oscillations, which basically originate from various junctions of the system. The magnitude of the oscillations is obviously dependent on the rise time of the incident currents. The tower base currents settle within about 10 -15 µs, which is shorter than that for isolated tower. Further, the full-frequency model could be limited to this time period. The corresponding current transfer functions are deduced. For the stroke interception by shield wires, based on the earlier work, only stroke to midspan is found to be relevant and hence it is considered. The nature of tower base currents for a stroke to midspan of the shield wires seem to be similar. However there are some distinct features, which are helpful in identifying the stroke location on the LPS. From the time correlated tower base currents, a suitable methodology for identifying the stroke interception location on LPS is developed. Next, simulations for induced current due to a bypass stroke, as well as, stroke to ground outside the LPS, however, within 1 km radius are taken up. In fact, it is estimated that latter is nearly 5 – 13 times higher than the strokes collected by LPS, indicating it as the most probable event. The objective here is characterization, rather than correlation. In this study, the influence of charge induced on the LPS by the descending leader is neglected and the upward leader activity is approximately considered. To the best of author’s knowledge, studies on such induced currents in down conductors are very scarce. Considering this and noting that the number of parameters is quite large, first the basic study is taken up on simple cylindrical down conductors. Many important and interesting deductions are made. The nature of the induced current is highly dependent on the rate of rise as well as the velocity of propagation of the stroke current. The magnitude and to some extent, the wave shape of the induced current is found to depend on the average as well as maximum di/dt of the stroke current. For a given wave shape, the magnitude of the induced current increases with rate of rise of the wave front; however, saturating trend will onset after some point. The height of the down conductor mainly governs the frequency of the oscillatory component of the induced current. The dependency of the induced current on the radius of the down conductor seems to be logarithmic (which is in accordance with the antenna theory). Based on these results, the parameters for the corresponding study on LPS under consideration, is chosen. The results of the investigation on the induced currents in LPS show that they have quite distinct waveform. They are basically bipolar and oscillatory in nature, with relatively short duration. These unique features facilitate clear distinction of the induced currents from that due to stroke interception. Basic characteristics are reasonably insensitive to the separation distance of the protection system and the channel, current propagation velocity along the channel, channel inclination and shape of the current front. The salient features of the induced current due to a bypass stroke are also enumerated. • The noise, if any, in the measured current can be addressed only after acquiring sufficient data. Based on the above, the following procedure is suggested for the stroke classification and estimation. • By employing the distinct features of the resulting tower base currents, analyze the measured tower base currents and classify the strokes into the intercepted stroke or stroke to ground. • For the latter case, using the salient features of the bypass strokes, further classify the strokes to bypass strokes and stroke to ground outside the protected volume. • For the intercepted strokes, using the relative strengths and wave shapes, identify the interception point to either tower top or the midspan of the shield wires. • Then by using the corresponding transfer functions and Fourier Transform techniques, compute the injected stroke current. • Using the above, other tower base currents are computed and compared with the measured currents. This gives quantification for the accuracy of the method. In summary the present work has made some original contribution to the classification and estimation of stroke currents measured on the interconnected LPS.

Pastaruoju metu galima pastebėti tendencingą prekių ženklo reikšmės didėjimą tiek vietinėje, tiek regioninėje, tiek ir tarptautinėje prekyboje, todėl kiekvienas prekių ženklo savininkas yra skatinamas skirti vis didesnį dėmesį tinkamam savo prekių ženklo valdymui bei apsaugai. Bendrijos prekių ženklo apsaugos sistema suteikia registruotam prekių ženklui apsaugą visoje Europos Sąjungos teritorijoje. Žymeniui, galinčiam tapti prekių ženklu ir naudotis Bendrijos prekių ženklo sistemos garantuojama apsauga, yra keliami gana aukšti grafinės išraiškos ir skiriamojo pobūdžio reikalavimai. Šie reikalavimai yra tenkinamai, jei žymens grafinė išraiška yra aiški, apibrėžta, išbaigta, lengvai prieinama, suprantama, ilgalaikė ir objektyvi, o žymens skiriamasis pobūdis leidžia aiškiai identifikuoti prekių ar paslaugų kilmę. / Recently it is possible to notice the tendentious increase of trade mark’s importance in local, regional and international market, therefore every trade mark proprietor shall be motivated to pay more and more attention to proper management and protection of their trade mark. Community Trade Mark’s Protection System provides the protection for the registered trade mark within the entirely territory of the European Union. Sign, capable of being a trade mark and using the guaranteed protection of the Community Trade Mark Protection System, shall follow the high requirements of graphical representation and distinctiveness. These requirements are fulfilled provided that the graphical representation is clear, precise, self-contained, easily accessible, intelligible and objective, where the distinctiveness of the sign allows clearly identify the origin of goods and services. Community Trade Mark proprietors may be every natural or legal person, including authorities established under public law. The rights of Community Trade Mark proprietor may be divided into the following main groups: (1) exclusive rights; and (2) ownership rights to the trade mark. The exclusive rights of the proprietor allows to prohibit all third parties without the permission of the proprietor from using in the course of trade the sign, which is identical or similar to the Community Trade Mark and which may confuse a consumer. When providing the proprietor of the trade mark with the respective rights, it is... [to full text]

Thermal Protection System (TPS) is required to shield an atmospheric entry vehicle against the high surface heating environment experienced during hypersonic flight. There are significant uncertainties in the tools and models currently used for the prediction of entry aeroheating and TPS material thermal response. These uncertainties can be reduced using experimental data. Analysis of TPS ground and flight data has been traditionally performed in a direct fashion. Direct analyses center upon comparison of the computational model predictions to data. Qualitative conclusions about model validity may be drawn based on this comparison and a limited number of model parameters may be iteratively adjusted to obtain a better match between predictions and data. The goal of this thesis is to develop a more rigorous methodology for the estimation of surface heating and TPS material response using inverse estimation theory. Built on theoretical developments made in related fields, this methodology enables the estimation of uncertainties in both the aeroheating environment and material properties from experimental temperature data. Unlike direct methods, the methodology developed here is capable of estimating a large number of independent parameters simultaneously and reconstructing the time-dependent surface heating profile in an automated fashion. This methodology is applied to flight data obtained from thermocouples embedded in the Mars Pathfinder and Mars Science Laboratory entry vehicle heatshields.

Då dagens vapensystem blir allt effektivare med högre penetration och större verkan är det inte längre möjligt att endast lägga på mer pansar för att få tillräckligt skydd. Fordonen blir för tunga och rörligheten påverkas negativt i allt för stor grad, därför börjar nu system för aktivt skydd slå sig in på marknaden. Dessa system söker aktivt av fordonets omgivning och skjuter ner inkommande hot såsom raketer och robotar och finns redan implementerade i en rad länder i vårt närområde. Infanteriets huvudbeväpning, som mot bepansrade hot traditionellt sett varit just robotar, raketer och granater, är i många fall verkanslös i mötet med aktivt pansar. Uppsatsen undersöker vilka möjligheter som finns att med den utrustning som dagens svenska försvarsmakt är utrustad med nå verkan i mål som är skyddade av aktivt pansar. De befintliga systemen för aktivt pansar Trophy, Iron Curtain och Arena har valts som exempelsystem. De vapensystem som granskas är STRIX, Rb56, Pskott m/86, Grg m/86 samt fordonsmina 14. En slutsats är att de granskade systemen alla saknar förmåga att skydda fordonet från hot som kommer rakt ovanifrån, detta medför att STRIX är fullt fungerande mot ett fordon skyddat av aktivt pansar. / Since today's weapons systems are becoming more efficient with higher penetration and greater efficacy, it is no longer possible to only put on more armor to get adequate protection. The vehicles become too heavy and mobility is adversely affected to an excessive degree, because of this systems for active protection are now breaking into the market. These systems are actively scanning the vehicle's surroundings and shoot down incoming threats such as rockets and robots and are already implemented in a number of countries in our region. The infantry's main armament against armored units, which traditionally have been just missiles, rockets and grenades are in many cases useless meeting with active protection systems. The paper examines the possibilities of reaching effect in targets equipped with active armor using the equipment available to the Swedish armed forces today. The existing active protection systems Trophy, Iron Curtain and Arena have been chosen as example systems. The weapons systems examined are STRIX , Rb56 , Pskott m/86 , Grg m/86 and Fordonsmina 14. One conclusion is that the audited systems all lack the ability to protect the vehicle from threats that come from directly above; this means that STRIX is fully functional to a vehicle protected by an active protection system.

本研究探討吹哨者保護制度對公司、員工與會計師產生之影響。模型結果顯示，完善的吹哨者保護制度可以提升員工的吹哨意願，進而使公司傾向誠實表達；完善的吹哨者保護制度可能增加或減少會計師的審計成本，會計師若預期公司因員工吹哨意願提高而傾向誠實表達，可降低審計成本，惟公司若不實表達且會計師並未經由查核發現時，會因為員工吹哨而產生商譽等重大損失。因此會計師於不同資本規模、客戶數量、事務所文化、員工素質等狀況下，會產生相異之審計成本變化。 / This study discusses the effect of Whistleblower protection system on firms, employees, and external auditors. Results of the models show that, a perfect Whistleblower protection system can motivate employees to blow the whistle and thus make the firm present honestly. A perfect Whistleblower protection system may increase or decrease external auditors’ audit costs. External auditors may decrease audit costs if they expect the firm will present honestly due to the enthusiasm of employees to blow the whistle, while external auditors may increase audit costs if they can’t afford the loss of goodwill when they couldn’t find the misstatement and the employee blowed the whistle. Therefore, external auditors have different changes in audit costs under different conditions, such as capital scale, number of clients, office culture and staff quality.

No description available.