229 research outputs found
The Paradox of the Benefiting Samaritan
Many persons believe that benefiting from injustice can be morally wrong. Philosophers have developed several compelling theories to justify this intuition. These theories, however, may have a difficult time explaining a particular set of benefit-from-injustice cases: cases in which the beneficiary subjectively opposes the injustice from which she objectively benefits. This paper suggests that our moral duties to disgorge the benefits of injustice may vary in proportion to our subjective intent in acquiring and using those benefits. In doing so, it reasons by analogy to other areas of moral and legal theory, including principles of compensation for unjust harms
Going Viral: Vaccines, Free Speech, and the Harm Principle
This paper analyzes the case of public anti-vaccine campaigns and examines
whether there may be a normative case for placing limitations on public speech of
this type on harm principle grounds. It suggests that there is such a case; outlines a
framework for when this case applies; and considers seven objections to the case for
limitation. While not definitive, the case that some limitation should be placed on
empirically false and harmful speech is stronger than it at first appears
Corridor Report on the United Kingdom The immigration, emigration and diaspora policiesâ effects on integration: Chinese and Indian Migrants in the UK
This paper presents the first results of the INTERACT project on Chinese and Indian migrants in the
United Kingdom (UK). It is based on the data gathered by the project using a mixed method of data
collection and analysis. We identify the policies of the states of origin (India and China) and
destination (the UK), their implementation and their impact on migrantsâ integration paths in the UK.
In this paper, we first present an overview of the evolution of Chinese and Indian migration flows to
the UK, and then present the current policy frameworks at both destination and origin, before
analysing how they affect the integration trends of Chinese and Indian migrants in the UK. Even
though contemporary Indian migrants â and to an even greater extent, Chinese migrants â living in the
UK are highly skilled migrants, they do not automatically integrate into British society. Although
Chinese migrants are better educated than Indian migrants, fewer hold a British passport, and more are
unemployed. The position of Chinese and Indian migrants in British society seems to be the
consequence of the combination of the origin and destination countriesâ policies. These policies indeed
influence current and past migration flows, namely through entry conditions to the UK, and exit
policies at origin. In addition, both the year of arrival and the duration of stay impact migrantsâ
integration. Since the migration flows from India are older than those from the Peopleâs Republic of
China (PRC), Indian migrants speak better English than Chinese migrants and more often own a
home, hold a British passport and identify as British. State policies at destination and origin also affect
the way that migrant communities are organized and integrated into mainstream society. Chinese
migrants, who in recent years have mainly been students, have more connections with the PRC than
Indian migrants do with their state of origin since new Chinese civil society organisations based in the
UK have close ties with the Chinese State. These associations are also aware of Chinese migrantsâ
potential difficulties with integration, and thus try to counterbalance it. Destination and origin policies
can thus affect migrantsâ opportunity structures differently over time and have both a direct and
indirect effect on migrant integration in the long run
Modelling and Simulation of Vehicle Models of different Complexity
Die vorliegende Arbeit besteht aus zwei Untersuchungsschwerpunkten. Zum einen wird die Erstellung und die Validierung von Mehrkörperfahrzeugmodellen beschrieben. Zum anderen wird das FahrgefĂŒhl des Fahrers an einem bewegten Fahrsimulator in AbhĂ€ngig-keit von der FahrzeugmodellkomplexitĂ€t bewertet.
ZunĂ€chst wurden exemplarisch zwei Fahrzeugmodelle unterschiedlicher KomplexitĂ€t er-stellt: ein generisches Fahrzeugmodell mit einer verhĂ€ltnismĂ€Ăig einfachen RadaufhĂ€n-gung und ein spezielles Fahrzeugmodell mit komplexen RadaufhĂ€ngungen. Die Modelle wurden auf der Grundlage eines topologischen Modellierungsansatzes zur Erstellung von Mehrkörpermodellen erstellt.
Das generische Fahrzeugmodell stellt durch seine vergleichsweise einfache Parametrie-rung ein vielseitig einsetzbares Modell dar. Zur Eigenschaftsabsicherung des generischen Modells wurde eine Vorgehensweise beschrieben, die eine SensitivitĂ€tsanalyse der Mo-dellparameter mit einer nachgeschalteten Parameteridentifikation enthĂ€lt. Das dafĂŒr not-wendig Referenzmodell wurde aus Fahrzeugdaten und Fahrdynamikmessungen erstellt und spiegelt die Kompaktklasse mit ihren spezifischen Parametern und ihrem typischen Fahrverhalten wider.
Das spezielle Fahrzeugmodell bildet eine bestimmte Fahrzeugklasse sehr genau ab. Die RadaufhĂ€ngungen werden dabei detailliert modelliert und können zudem modular ausge-tauscht werden, wodurch eine Ausgangsbasis fĂŒr unterschiedliche Fahrzeugtypen ge-schaffen wird. FĂŒr diesen modularen Ansatz wurden speziell eine MacPherson-Federbeinvorderachse und eine Mehrlenkerhinterachse umfassend hergeleitet. Die Radki-nematik der Vorder- und Hinterachse wurde anhand von gemessenen Anlenkpunkten si-muliert. Der simulierte Sturz- und Spurwinkelverlauf beider Achsen wurde mit Messungen verglichen und bewertet. Daraufhin wurden das generische und spezielle Fahrzeugmodell anhand einer stationĂ€ren Kreisfahrt fahrdynamisch gegeneinander ver-glichen und bewertet.
Das generische Modell konnte sehr gut an das Referenzmodell angepasst werden. Schon ein minimaler Satz an Parametern reicht aus, um das Fahrverhalten angemessen an die des Referenzmodells anzupassen. Auch wenn das generische Fahrzeugmodell sich vom speziellen Fahrzeugmodell in der Nachbildungstiefe unterscheidet, ist die Wiedergabe des Fahrverhaltens genĂŒgend und fĂŒr viele AnwendungsfĂ€lle und Untersuchungen mehr als ausreichend. Zudem benötigt das generische, im Vergleich zum speziellen Fahrzeugmo-dell, weniger Rechenzeit und ist dadurch echtzeitfĂ€hig. FĂŒr viele Anwendungen, bei de-nen es auf die Rechenzeit ankommt, ist das generische Fahrzeugmodell ein willkommener Kompromiss zwischen Rechenzeit und AbbildungsgĂŒte. Zudem besticht das generische Fahrzeugmodell durch seine AnpassungsfĂ€higkeit an unterschiedliche Fahrzeugklassen.
AbschlieĂend wurde in einem Praxistest das FahrgefĂŒhl des Fahrers an einem bewegten Fahrsimulator in AbhĂ€ngigkeit von der FahrzeugmodellkomplexitĂ€t durch eine Signifikanzuntersuchung bewertet. In dieser Probandenstudie wurden ein Einspurmodell (Mo-dell A), ein erweitertes Einspurmodell (Modell B), ein Zweispurmodell mit vergleichsweise einfacher RadaufhĂ€ngung (Modell C) und das generische Zweispurmodell (Modell D) verwendet. Die Modelle A-D wurden validiert, um das Fahrverhalten des Referenz-modells wiederzugeben.
Die Untersuchungen ergaben, dass der ModellkomplexitĂ€tsgrad nicht notwendigerweise hoch sein muss, um den Fahrer ausreichend in die hier gestellte Fahraufgabe und die Si-mulationsumwelt einzugewöhnen. Obwohl Modell C mit einer einfachen und Modell D mit einer komplexen RadaufhĂ€ngung modelliert wurden, konnten bei den gefahrenen Manövern keine signifikanten Unterschiede im subjektiven Fahrverhalten festgestellt werden. Zudem ist anzumerken, dass Modell B trotz seiner verhĂ€ltnismĂ€Ăig einfachen Modellierung fĂŒr einen groĂen Teil an Fahraufgaben am Fahrsimulator empfohlen wer-den kann, da es einen guten und weitgehend realistischen Fahrerimmersionsgrad realisiert.This work focuses on two topics. One is the modelling of multibody vehicle model and its verification. The other is the investigation of the subjective driving perception of human drivers in a dynamic driving simulator in dependency of the vehicle model complexity.
In the beginning of this work two vehicle models of different complexity level were de-veloped. One generic vehicle model with relatively simple wheel suspensions and a special vehicle model with a more complex wheel suspension. The models were derived with help of a topological multibody modeling techniques.
The generic vehicle model can be used in versatile assignments due to its relatively simple parameterization. To validate the characteristics of the generic model a process is used which investigates the sensitivity of the model parameter and applies thereafter parameter identification. The required reference model is derived from vehicle data and vehicle dy-namics measurements and mirrors the performance of a compact class with its specific parameters.
The special vehicle model explicitly maps the performance of a given vehicle class. The vehicle suspension are detailed modelled und can be modularly exchanged. This is a basis for creating different vehicle types in more detail. For this modular approach the Mac-Pherson strut front axle and the multi-link rear axle are derived in detail. The suspension kinematics for the front and rear axle are simulated on the basis of measured pivot points. The simulated camber and caster angle of both axles are compared and evaluated with measurements. Hereupon the driving performance of the generic and the special vehicle model were compared and evaluated by means of a circular driving under steady state conditions.
The generic vehicle model could be mapped onto the reference model very well. A mini-mal set of optimized parameter were sufficient to reasonable adapt its characteristic to the reference vehicle. Although the level of detail of the special model could not be reached by the generic model, the reproduction of the driving behaviors through the generic model was adequate and in many cases more the sufficient. Moreover the generic model needs less computational time compared to the special model and is thus usable for many appli-cations which depend on real time computations. The generic model is a reasonable com-promise between computational time and simulation quality and is flexible adapted to a variety of vehicle types.
This work concludes with an investigation of the subjective driving perception of human drivers in a dynamic driving simulator in dependency of the vehicle model complexity with help of a human subjects study. Four vehicle models of different complexity are used to compute the simulatorâs motion. The models used are the single-track model (model A), the single-track model extended with roll motion (model B), a two-track mod-el with a simple suspension model for vertical wheel motion (model C) and the generic vehicle model (model D). The models A-D were validated to match the motion of a refer-ence vehicle performing a steer step maneuver.
In conclusion, the model complexity does not need to be high to immerse a driver into a simulative driving task. Although models C and D differ in the complexity level of the modeled wheel suspension, there was no significant difference in the subjective driving feeling while driving the given driving task. It is remarkable that model B with its com-paratively simple modeling is good enough to immerse the driver into the driving task. This model can be recommended for a broad band of driving tasks in simulators
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SECONDARY WASTE MANAGEMENT FOR HANFORD EARLY LOW ACTIVITY WASTE VITRIFICATION
More than 200 million liters (53 million gallons) of highly radioactive and hazardous waste is stored at the U.S. Department of Energy's Hanford Site in southeastern Washington State. The DOE's Hanford Site River Protection Project (RPP) mission includes tank waste retrieval, waste treatment, waste disposal, and tank farms closure activities. This mission will largely be accomplished by the construction and operation of three large treatment facilities at the Waste Treatment and Immobilization Plant (WTP): (1) a Pretreatment (PT) facility intended to separate the tank waste into High Level Waste (HLW) and Low Activity Waste (LAW); (2) a HLW vitrification facility intended to immobilize the HLW for disposal at a geologic repository in Yucca Mountain; and (3) a LAW vitrification facility intended to immobilize the LAW for shallow land burial at Hanford's Integrated Disposal Facility (IDF). The LAW facility is on target to be completed in 2014, five years prior to the completion of the rest of the WTP. In order to gain experience in the operation of the LAW vitrification facility, accelerate retrieval from single-shell tank (SST) farms, and hasten the completion of the LAW immobilization, it has been proposed to begin treatment of the low-activity waste five years before the conclusion of the WTP's construction. A challenge with this strategy is that the stream containing the LAW vitrification facility off-gas treatment condensates will not have the option of recycling back to pretreatment, and will instead be treated by the Hanford Effluent Treatment Facility (ETF). Here the off-gas condensates will be immobilized into a secondary waste form; ETF solid waste
Understanding the Photoexcitation of Room Temperature Ionic Liquids
Photoexcitation of (neat) room temperature ionic liquids (RTILs) leads to the observation of transient species that are reminiscent of the composition of the RTILs themselves. In this minireview, we summarize stateâofâtheâart in the understanding of the underlying elementary processes. By varying the anion or cation, one aim is to generally predict radiationâinduced chemistry and physics of RTILs. One major task is to address the fate of excess electrons (and holes) after photoexcitation, which implies an overview of various formation mechanisms considering structural and dynamical aspects. Therefore, transient studies on time scales from femtoseconds to microseconds can greatly help to elucidate the most relevant steps after photoexcitation. Sometimes, radiation may eventually result in destruction of the RTILs making photostability another important issue to be discussed. Finally, characteristic heterogeneities can be associated with specific physicochemical properties. Influencing these properties by adding conventional solvents, like water, can open a wide field of application, which is briefly summarized
Versteckte Anerkennungsmechanismen
Mit welchen Herausforderungen sehen sich MittelschullehrkraÌfte im Musikunterricht konfrontiert und gibt es einen Zusammenhang zwischen dem unterrichtsbezogenen BewaÌltigungshandeln der LehrkrĂ€fte sowie der Entstehung dieser Herausforderungen? Diese Fragen stehen im Zentrum der empirisch-qualitativ ausgerichteten Interviewstudie.
Ausgehend von der These, dass die BewĂ€ltigung einer Herausforderung Auswirkungen auf die nachfolgende Unterrichtssituation hat und daher möglicherweise auch als Auslöser von Herausforderungen wirksam ist, werden die von den interviewten LehrkrĂ€ften benannten Herausforderungsfaktoren von Musikunterricht systematisiert und das zugehörige BewĂ€ltigungshandeln nĂ€her beleuchtet. Ziel der Studie ist es, anhand der EntschlĂŒsselung versteckter Anerkennungsmechanismen mögliche unbeabsichtigte Effekte unterrichtsbezogener BewĂ€ltigung nĂ€her zu bestimmen. Ein analytisch gewendeter Anerkennungsbegriff fungiert hierfĂŒr bei der Interpretation der evaluierten BewĂ€ltigungsstragien als heuristisches Bezugskonzept.
Als mögliche methodisch-didaktische Perspektive wird vor dem Hintergrund der erzielten Forschungsergebnisse das Konzept der Anerkennung als unterrichtsbezogene Reflexionskategorie konkretisiert.
Monika Unterreiner studierte MusikpĂ€dagogik, Neuere und Neueste Geschichte, Didaktik der Geschichte (M. A.) und Lehramt fĂŒr Mittelschulen an der Ludwig-Maximilians-UniversitĂ€t MĂŒnchen sowie Schulmusik an der Hochschule fĂŒr Musik und Theater MĂŒnchen. Die vorliegende Studie ist aus ihrer Promotion an der Schnittstelle von MusikpĂ€dagogik und SchulpĂ€dagogik hervorgegangen. Ihre Forschungsschwerpunkte liegen in den Bereichen "Unterrichtsentwicklung" und "pĂ€dagogische ProfessionalitĂ€t"
Relaxation Dynamics of Electronically Excited C60â in o-Dichlorobenzene and Tetrahydrofuran Solution
The ultrafast response of singly negatively charged C60 fullerene in solution has been investigated by femtosecond pump-probe absorption spectroscopy and transient anisotropy in the visible and near-infrared region. Pump excitation within the near-infrared band demonstrates that this spectral feature can be described as avibrational progression associated with asingle electronic transition. Relaxation of the first electronically excited state occurs primarily by internal conversion with atime constant of 3ps, slightly depending on the solvents, tetrahydrofuran or o-dichlorobenzene, and also on the excitation wavelength. An excitation of the second electronically excited state around 530nm leads to an ultrafast internal conversion to the first excited state with apulse-limited time constant of less than 100fs. As aminor channel, stimulated emission in the spectral regime of 1150-1300nm was observed from the first electronically excited state both after near-infrared and visible excitation. After internal conversion to the electronic ground state, C60â dissipates its excess internal energy into the solvent on alonger timescale of 40-70ps. The transient anisotropy associated with directly populating the first excited state reveals an ultrafast component decaying within 100fs, which is attributed to ultrafast vibrational motions, conceivably arising from excited state pseudorotatio
Photoexcitation of Ge9 Clusters in THF: New Insights into the Ultrafast Relaxation Dynamics and the Influence of the Cation
We present a comprehensive femtosecond (fs) transient absorption study of the [Ge(Hyp)] (Hyp = Si(SiMe3)3) cluster solvated in tetrahydrofuran (THF) with special emphasis on intra- and intermolecular charge transfer mechanisms which can be tuned by exchange of the counterion and by dimerization of the cluster. The examination of the visible and the near infrared (NIR) spectral range reveals four different processes of cluster dynamics after UV (267/258 nm) photoexcitation related to charge transfer to solvent and localized excited states in the cluster. The resulting transient absorption is mainly observed in the NIR region. In the UV-Vis range transient absorption of the (neutral) cluster core with similar dynamics can be observed. By transferring concepts of: (i) charge transfer to the solvent known from solvated Na in THF and (ii) charge transfer in bulk-like materials on metalloid cluster systems containing [Ge(Hyp)] moieties, we can nicely interpret the experimental findings for the different compounds. The first process occurs on a fs timescale and is attributed to localization of the excited electron in the quasi-conduction band/excited state which competes with a charge transfer to the solvent. The latter leads to an excess electron initially located in the vicinity of the parent cluster within the same solvent shell. In a second step, it can recombine with the cluster core with time constants in the picosecond (ps) timescale. Some electrons can escape the influence of the cluster leading to a solvated electron or after interaction with a cation to a contact pair both with lifetimes exceeding our experimentally accessible time window of 1 nanosecond (ns). An additional time constant on a tens of ps timescale is pronounced in the UV-Vis range which can be attributed to the recombination rate of the excited state or quasi conduction band of Ge. In the dimer, the excess electron cannot escape the molecule due to strong trapping by the Zn cation that links the two cluster cores
Chronotropic response to exercise in patients with peripheral arterial disease without classical symptoms of intermittent claudication
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