Is There a Federal Definitions Power?

Although the Supreme Court decided United States v. Windsor on equal protection grounds, that case also raised important and recurring questions about federal power. In particular, defenders of the Defense of Marriage Act (DOMA) argued that Congress may always define the terms used in federal statutes, even if its definition concerns a matter reserved to the States. As the DOMA illustrates, federal definitions concerning reserved matters that depart from state law may impose significant burdens on state governments and private citizens alike. This Article argues that there is no general, freestanding federal definitions power and that sometimes—as with marriage—federal law must incorporate state law definitions

Införandet av mål för God ekonomisk hushållning i Skånes kommuner

Syfte: Uppsatsens syfte är att studera hanterandet av mål för god ekonomisk hushållning i kommunen och dess påverkan på den kommunala revisionen, för att analysera fenomenets roll i styrningen av kommunen. Metod: I enlighet med målet att uppfylla uppsatsens syfte har vi valt att genomföra en kvalitativ undersökning med en deskriptiv ansats. Uppsatsens primärdata har införskaffats genom nio intervjuer av ekonomichefer, politiker och förtroendevalda revisorer i Helsingborgs, Kävlinge och Osby kommun. Vi har även genomfört fyra intervjuer med sakkunniga biträden. Sekundärdata har samlats in i form av kommunala finansiella dokument. Institutionalia och teorier har samlats in i huvudsak från lämplig facklitteratur och forskningsartiklar. Teoretiska perspektiv: I uppsatsen har vi valt att presentera och diskutera agentteorin av Jensen och Meckling. Mål för god ekonomisk hushållning kopplas till målstyrning och till Kaplan och Nortons balanserade styrkort. Vi undersöker revisorns roll i den kommunala revisionen, samt presenterar Carl Liggios teori om förväntningsgap och slutligen Streeck och Schmitters teori om regleringens uppbyggnad Empiri: Undersökningen av Skånes 33 kommuners finansiella dokument för delåret 2006, samt revisorernas utlåtande visar att ca 21 % av kommunerna har upprättat och följt upp verksamhetsmål. Ca 85 % har, enligt revisorerna, på ett tillfredsställande sätt upprättat och följt upp finansiella mål för god ekonomisk hushållning. Slutsats: Undersökning visar att Skånes kommuner överlag inte uppfyller lagens krav på finansiella och verksamhetsmässiga mål kopplade till god ekonomisk hushållning. Vidare ser vi de sakkunniga biträdena, det vill säga auktoriserade och certifierade revisorer, som viktiga för att processen med framtagande av mål skall komma igång ute i kommunerna och även då som garanter för att en framtida utvecklig drivs och utvecklas

Theory and experiment of entanglement in a quasi-phase-matched two-crystal source

We report new results regarding a source of polarization entangled photon-pairs created by the process of spontaneous parametric downconversion in two orthogonally oriented, periodically poled, bulk KTiOPO4 crystals (PPKTP). The source emits light colinearly at the non-degenerate wavelengths of 810 nm and 1550 nm, and is optimized for single-mode optical fiber collection and long-distance quantum communication. The configuration favors long crystals, which promote a high photon-pair production rate at a narrow bandwidth, together with a high pair-probability in fibers. The quality of entanglement is limited by chromatic dispersion, which we analyze by determining the output state. We find that such a decoherence effect is strongly material dependent, providing for long crystals an upper bound on the visibility of the coincidence fringes of 41% for KTiOPO4, and zero for LiNbO3. The best obtained raw visibility, when canceling decoherence with an extra piece of crystal, was 91 \pm 0.2%, including background counts. We confirm by a violation of the CHSH-inequality (S = 2.679 \pm 0.004 at 55 s^{-1/2} standard deviations) and by complete quantum state tomography that the fibers carry high-quality entangled pairs at a maximum rate of 55 x 10^3 s^{-1}THz^{-1}mW^{-1}.Comment: 12 pages, 10 figures, REVTeX

Optimal focusing for maximal collection of entangled narrow-band photon pairs into single-mode fibers

We present a theoretical and experimental investigation of the emission characteristics and the flux of photon pairs generated by spontaneous parametric downconversion in quasi-phase matched bulk crystals for the use in quantum communication sources. We show that, by careful design, one can attain well defined modes close to the fundamental mode of optical fibers and obtain high coupling efficiencies also for bulk crystals, these being more easily aligned than crystal waveguides. We distinguish between singles coupling, conditional coincidence, and pair coupling, and show how each of these parameters can be maximized by varying the focusing of the pump mode and the fiber-matched modes using standard optical elements. Specifically we analyze a periodically poled KTP-crystal pumped by a 532 nm laser creating photon pairs at 810 nm and 1550 nm. Numerical calculations lead to coupling efficiencies above 94% at optimal focusing, which is found by the geometrical relation L/z_R to be ~ 1 to 2 for the pump mode and ~ 2 to 3 for the fiber-modes, where L is the crystal length and z_R is the Rayleigh-range of the mode-profile. These results are independent on L. By showing that the single-mode bandwidth decreases as 1/L, we can therefore design the source to produce and couple narrow bandwidth photon pairs well into the fibers. Smaller bandwidth means both less chromatic dispersion for long propagation distances in fibers, and that telecom Bragg gratings can be utilized to compensate for broadened photon packets--a vital problem for time-multiplexed qubits. Longer crystals also yield an increase in fiber photon flux proportional to sqrt{L}, and so, assuming correct focusing, we can only see advantages using long crystals.Comment: 19 pages, 15 figures, ReVTeX4, minor revisio

How product characteristics can guide measures for resource efficiency - A synthesis of assessment studies

A circular economy aims at decoupling value creation from resource throughput. For circular economy to contribute to environmental and resource improvements, there is need for critical assessments regarding in what general situations, beyond individual cases, solutions may lead to improvements. On the product-level, there is need for synthesized knowledge accounting for a wide range of contexts and environmental impacts. We investigate what resource efficiency (RE) measures result in reduced physical flows and environmental impacts, depending on the characteristics of products and their life cycles. The study is limited to physical measures on a product system level, irrespective of manner of implementation. A library of comparative assessments (primarily life cycle assessments and material flow analyses) was built, covering a wide range of products and RE measures. A framework was formulated for analysing for which product characteristics a measure tends to improve RE, and under which contexts there are trade-offs to take into account. For example, sharing of products is best suited for durable and infrequently used products that tend not to reach their full technical lifetime. A trade-off is that sharing can increase transportation for accessing shared stock. The identified key product characteristics were: whether products are consumable or durable, active or passive, typically used for their full technical lifetimes or discarded before being worn out, the product’s frequency of use and whether function remains at a product’s end of use. Pace of development matters for suitability of measures for active, durable products, while complexity is relevant for restorative measures and recycling

Highly Efficient Source for Indistinguishable Photons of Controlled Shape

We demonstrate a straightforward implementation of a push-button like single-photon source which is based on a strongly coupled atom-cavity system. The device operates intermittently for periods of up to 100 microseconds, with single-photon repetition rates of 1.0 MHz and an efficiency of 60 %. Atoms are loaded into the cavity using an atomic fountain, with the upper turning point near the cavity's mode centre. This ensures long interaction times without any disturbances induced by trapping potentials. The latter is the key to reaching deterministic efficiencies as high as obtained in probabalistic photon-heralding schemes. The price to pay is the random loading of atoms into the cavity and the resulting intermittency. However, for all practical purposes, this has a negligible impact

A high-brightness source of polarization-entangled photons optimized for applications in free space

We present a simple but highly efficient source of polarization-entangled photons based on spontaneous parametric down-conversion (SPDC) in bulk periodically poled potassium titanyl phosphate crystals (PPKTP) pumped by a 405 nm laser diode. Utilizing one of the highest available nonlinear coefficients in a non-degenerate, collinear type-0 phase-matching configuration, we generate polarization entanglement via the crossed-crystal scheme and detect 0.64 million photon pair events/s/mW, while maintaining an overlap fidelity with the ideal Bell state of 0.98 at a pump power of 0.025 mW