59,145 research outputs found
Auditorâs Liability and the Need for Increased Accounting Uniformity
The work aims to study different methods suitable for de-icing and ice prevention of vehicle headlamps and tail lamps, especially LED-lights. Furthermore, the work aims to investigate the scale of the problem with insufficient or lack of de-icing on automotive lamps depending on the region and the environment the vehicle operates in. The problem with insufficient de-icing in automotive lamps was investigated by observations, tests of various lamps and a driver survey. Deicing methods were identified through a litera-ture review. The methods were studied in detail, and some were also evaluated by tests. The tests were narrowed down to temperature measurements and de-icing measurements. The latter were performed using a test method especially developed for the task. The collected data was used to evaluate whether actions are needed to be taken and to form recommen-dations for future developments. The number one priority should be to improve the tail lamps de-icing ability. Headlamps can also be improved but there is no imminent need. Insufficient de-icing of headlamps and tail lamps can potentially be a problem in all areas subjected to cold winter climate. Tail lamps should be fitted with electrical heating in order to improve the de-icing ability. They should be positioned so that snow and ice does not stack on top of them. The de-icing time of tail lamps should be less than 10 min. Truck drivers needs to be better in scraping their headlamps and tail lamps. The time needed for de-icing Scaniaâs H7 headlamps is 20 min for halogen version and 35 min for xenon version at -18 °C. This should be compared to the BMW LED-headlamp which needs 65 min to complete de-icing. LED-headlamps are probably limited to a de-icing time of approximately 60 min unless additional heat is added to the headlamp lens. The fastest and most efficient way to de-ice the headlamps is to use hot washer fluid. Electrically heated lenses are also effective but the de-icing process is slower. The proposed test method is a simple and effective way to compare and evaluate headlamps and tail lamps without knowing internal airflows and light sources. The way the ice layer is created on the device under test is unique to this method. The created ice layer is extremely uniform and the results are easy to evaluate.Sammanfattning Arbetets syfte Ă€r att undersöka olika avisningsmetoder och isförebyggande Ă„tgĂ€rder för hu-vudstrĂ„lkastare och baklyktor, speciellt LED-lampor. Ytterligare syfte Ă€r att undersöka hur stort problemet med otillrĂ€cklig avisning Ă€r beroende pĂ„ vilken region och miljö som fordonen körs i. Problemet med otillrĂ€cklig avisning av fordonsbelysning har undersökts genom observatio-ner, en förarenkĂ€t samt genom tester av olika strĂ„lkastare och baklyktor. Avisningsmetoder har identifierats genom en litteraturstudie. Metoderna har studerats i detalj och nĂ„gra har Ă€ven utvĂ€rderats genom tester. Testerna har utförts enligt en för uppgiften framtagen testme-tod. De insamlade uppgifterna har sedan anvĂ€nds för att utvĂ€rdera om Ă„tgĂ€rder behöver vid-tas och för att ge rekommendationer för framtida utvecklingsprojekt. Första prioritet bör vara att förbĂ€ttra baklyktornas avisningsförmĂ„ga. HuvudstrĂ„lkastarna kan Ă€ven de förbĂ€ttras men det föreligger inte i dagslĂ€get nĂ„got akut behov av det. OtillrĂ€cklig avisning av huvudstrĂ„lkastare och bakljus kan potentiellt vara ett problem i alla miljöer med ett kallt vinterklimat. Baklyktorna bör utrustas med en eluppvĂ€rmd lins för att förbĂ€ttra avis-ningen. Lamporna bör placeras pĂ„ ett sĂ„dant sĂ€tt att snö och is inte kan ansamlas ovanpĂ„ dem. Avisningstiden för en baklykta bör inte överstiga 10 min. Lastbilschaufförerna behöver bli bĂ€ttre pĂ„ skrapa av is och snö frĂ„n huvudstrĂ„lkastare och baklyktor. Avisningstiden för Scanias H7 huvudstrĂ„lkastare Ă€r 20 min för halogen versionen och 35 min för xenon versionen vid -18 °C. Detta kan jĂ€mföras med att BMW:s LED-huvudstrĂ„lkastare behöver 65 min för att avisas. LED-huvudstrĂ„lkastare Ă€r troligtvis begrĂ€nsade till en avis-ningstid kring 60 min om inte nĂ„gon extra vĂ€rme tillförs. Den snabbaste metoden för att avisa en huvudstrĂ„lkastare Ă€r att anvĂ€nda varm spolarvĂ€tska men elektrotermisk avisning kan ocksĂ„ vara mycket effektivt. Den föreslagna testmetoden Ă€r ett enkelt sĂ€tt att jĂ€mföra och utvĂ€rdera olika huvudstrĂ„lkastare och baklyktor. Det som Ă€r unikt med testmetoden Ă€r hur isskiktet pĂ„ lamporna bildas. Isskiktet som skapas Ă€r extremt jĂ€mt och lĂ€tt att utvĂ€rdera
Discretising the velocity distribution for directional dark matter experiments
Dark matter (DM) direct detection experiments which are
directionally-sensitive may be the only method of probing the full velocity
distribution function (VDF) of the Galactic DM halo. We present an angular
basis for the DM VDF which can be used to parametrise the distribution in order
to mitigate astrophysical uncertainties in future directional experiments and
extract information about the DM halo. This basis consists of discretising the
VDF in a series of angular bins, with the VDF being only a function of the DM
speed within each bin. In contrast to other methods, such as spherical
harmonic expansions, the use of this basis allows us to guarantee that the
resulting VDF is everywhere positive and therefore physical. We present a
recipe for calculating the event rates corresponding to the discrete VDF for an
arbitrary number of angular bins and investigate the discretisation error
which is introduced in this way. For smooth, Standard Halo Model-like
distribution functions, only angular bins are required to achieve an
accuracy of around in the number of events in each bin. Shortly after
confirmation of the DM origin of the signal with around 50 events, this
accuracy should be sufficient to allow the discretised velocity distribution to
be employed reliably. For more extreme VDFs (such as streams), the
discretisation error is typically much larger, but can be improved with
increasing . This method paves the way towards an astrophysics-independent
analysis framework for the directional detection of dark matter.Comment: 36 pages, 11 figures. Matches version accepted in JCAP. Python code
for Radon transform calculation available from the autho
Guatemala Holiday
Roll 6. Lodger's Picnic. Image 14 of 21. (18 May, 1952) [PHO 1.6.13]The Boleslaus Lukaszewski (Father Luke) Photographs contain more than 28,000 images of Saint Louis University people, activities, and events between 1951 and 1970. The photographs were taken by Boleslaus Lukaszewski (Father Luke), a Jesuit priest and member of the University's Philosophy Department faculty
Eisenhower and Montgomery: Strategy, Leadership, and Tension at the End of World War II
In late 1944, two legendary generals stood at the helm of the Allied Expeditionary Force as it plunged into Nazi Germany in an effort to end the Second World War. While the relationship between the United States and Britain, and more specifically the relationship between Generals Dwight Eisenhower and Bernard Montgomery are portrayed as cooperative, smooth, and friendly, personal memoirs of the two men and their close confidants reveal that these myths could not be further from the truth. A debate between the two men, which began as one regarding military strategy, escalated into a full blown feud; this tension was a reflection of the overlaying tensions of a changing Western world
- âŠ