Passive Regime Research Articles

Fiscal Activism and the Cost of Debt Financing

In this paper, we estimate the impact of changes in fiscal policy regime on the yield curve. In particular, we differentiate between yield curve responses under active and passive fiscal policy regimes (according to the terminology of Leeper 1991). Analyzing US data in the period 1965-2010, we find a statistically significant impact of fiscal policy only for the active policy regime. A one-percentage-point shock in the primary deficit leads typically to a contemporaneous increase in long-term yields of about 10 basis points, and even stronger cumulative effects. No significant impact of deficits on yields is found in the passive fiscal policy regime.

Upper Riphean and Vendian sandstones of the Bashkirian anticlinorium

The analysis of lithogeochemical data on the Upper Riphean and Vendian sandstones from the Bashkirian anticlinorium showed that sandstone associations formed in a passive sluggish tectonic regime in the middle Late Vendian were replaced by associations accumulated in the more active tectonic settings. This is well seen in the SiO2-K2O/Na2O and (Fe2 + MgO)-TiO2 diagrams reflecting the particular and median compositions of psammites. The lithochemical characteristics of sandstones were examined to deter� mine the compositional variation of rock complexes eroded on paleodrainage areas. Quartzrich sedimentary, metasedimentary, and metamorphic rocks, as well as felsic igneous rocks prevailed in the paleodrainage areas throughout the entire Late Riphean and Early Vendian, while the main sources of clastic material in the Late Vendian were igneous intermediate and basic rocks. With allowance made for the previous comparativelitho� logical data and some other materials, significant similarity in the position and orientation of compositional fields of psammites from the middle and upper levels of the Asha Group (Bashkirian anticlinorium) with fields of psammites from different syncollisional (flysch and molasse) basins in the SiO2-K2O/Na2O, K2 O/Na 2 O-SiO 2 /Al 2 O 3 , F1-F2 and other diagrams suggests that the middle Late Vendian (beginning from the Basa level) was marked by a variation in tectonic/geodynamic settings of sandstone accumulation and in composition of the eroded paleodrainage systems. The revealed trend agrees well with concept of the exist� ence of the Late Riphean-Vendian Pechora paleocean.

The structural features and petroleum resource potential of basins in the western and northwestern Australian margins

The oil and gas basins of Australia are confined to its western and northwestern margins. They are typical pericontinental depressions in the continent-ocean transition zone with a passive tectonic regime. The following oil and gas basins are definable from the south to northward: the Perth, Carnarvon, Canning, Browse, and Bonaparte. All these basins are well studied. Among them, the Carnarvon basin is the most productive. Despite the discovery of approximately a hundred oil and gas fields in this basin, its continental slopes are still insufficiently known. In this connection, the morphostructural features of the productive areas were analyzed using a specialized GIS technique. The performed analysis of the Carnarvon hydrocarbon-bearing basin demonstrated the efficiency of this technique and allowed several promising zones located west, north, and south of the discovered oil and gas fields and forming a single trend with them to be outlined. The total reserves of the country are as high as 2.1 × 109 t of oil and 840 × 109 m3 of gas. The annual oil production in Australia by January 1, 2008 was 22.25 × 106 t of oil and 14 × 109 m3 of gas. Approximately 95% of the oil and 80% of the gas produced in Australia by the beginning of 2008 were obtained from offshore parts of its basins.

CW and femtosecond operation of a diode-pumped Yb:BaY_2F_8 laser

We report for the first time on laser action of a diode-pumped Yb:BaY(2)F(8) crystal. Both CW and femtosecond operations have been demonstrated at room-temperature conditions. A maximum output power of 0.56 W, a slope efficiency of 34%, and a tunability range from 1013 to 1067 nm have been obtained in CW regime. Transform-limited pulse trains with a minimum duration of 275 fs, an average power of 40 mW, and a repetition rate of 83 MHz have been achieved in a passive mode-locked regime using a semiconductor saturable absorber mirror.

High Temperature Oxidation of SiC under Helium with Low Oxygen Partial Pressure

The Gas-cooled Fast Reactor (GFR) is one system of the Generation IV International Forum systems studied by CEA (France). The coolant considered is helium pressurized at 7 MPa and the nominal working temperature is about 1300 K. In case of accident, the reactor temperature can reach 1900 to 2300 K. Several studies are carried out to determine the physico-chemical behavior of structural materials undergoing various environmental constraints. The cladding material currently considered is SiC. Numerical calculations are carried out to determine the transition between passive and active oxidation regimes. Then an experimental study is performed to fix the position of the transition and to study the oxidation resistance of the two polymorphs α- and β-SiC at high temperature (1300 to 2300 K), coupled to a material characterization based on mass variation, SEM, XPS, AFM and roughness analyses.

Contrasting fluid events giving rise to apparently similar diagenetic products; late-stage dolomite cements from the Southern Alps and central Apennines, Italy

Abstract Precipitation of dolomite cements in Jurassic carbonate platform sediments and slope breccias has been studied from well cores and outcrops of the central Southern Alps and central Apennines in Italy. In both areas, an initial, massive dolomite replacement was followed by multiphase precipitation of dolomite cements. The replacement occurred during burial, in a passive margin regime, in response to compaction-driven flow of formational fluids. This interpretation is based on results from fluid inclusion and stable isotope analyses which have been related to the thermal history. The dolomite cements precipitated when both areas were involved in collisional tectonics. In spite of the similar diagenetic evolution, the fluids causing dolomite cementation in each case were compositionally different. In the Alps a decrease in salinity was recorded from sea water to brackish fluids, whereas in the Apennines an increase in salinity from sea water up to >10% NaCl equivalent was recorded. The remarkable salinity differences in diagenetic fluids are considered to be related to the different sub-aerial relief of the two belts during dolomite precipitation. In the Alps, the dilution of fluids is related to the infiltration of meteoric waters from the mountain chain, that was widely emergent. In the Apennines, dolomite cements precipitated whilst the structural units were still widely submerged, preventing meteoric dilution of cementing fluids and promoting an increase in salinity through mixing with fluids rising from older evaporate-bearing layers. In both Alpine and Apennine cases, the same diagenetic trend is observed in thrust-fold belt and foreland basin units; in both structural systems the diagenetic events start precipitating dolomite cements in the inner part of the collision zone and then the diagenetic processes migrate towards the foreland basin along with the structural evolution of the area.

New ytterbium-phosphate glass for diode-pumped lasers

A new ytterbium laser glass based on an alumoborophosphate composition is developed. It is shown that the chemical and thermal stabilities of this glass are record-high for phosphate glasses and that its spectral and luminescent characteristics compare well with popular laser glasses. A mould of laser-quality glass doped with ytterbium with a concentration of 5×1020 cm-3 is synthesised. Active laser elements 5×5×2 mm in size are prepared from this glass for longitudinal diode pumping. These elements were used to fabricate a laser, whose output power in the cw regime reached 783 mW and maximum slope efficiency was 28.9%. Pulses with a duration of ∼150 fs and a peak power of about 5 kW are obtained in the passive mode-locking regime.

Optical bifurcated fiber diode-pumping for two-wavelength laser operation with the Yb3+-doped GdAl3(BO3)4 birefringent crystal

Thanks to diode pumping through an optical bifurcated fiber, we take benefit of the birefringence of the Yb3+-doped GdAl3(BO3)4 crystal to get two-polarization and two-wavelength laser operation both in CW and in passive Q-switch regimes. Typical differential slopes are 54% and 30% respectively for the o- and e-waves. In the pulse regime the two o- and e-pulses are synchronous but not simultaneous. Free running laser emissions near 1040 and 1046 nm for the e- and o-waves respectively were obtained with 2.5 nm FWHM.

A STUDY OF SOLID STATE LASER PASSIVE OPTICAL Q-SWITCHING OPERATION REGIME (Part 1)

This paper is the first of a four series treating, theoretically with experimental comparison, the issue of solid state laser passive optical Q-switching regime. In this first paper the technique of solid state lasers passive optical Q-switching is numerically investigated considering the case of longitudinally and transversally uniform photon, population inversion and absorption centres densities. The coupled differential equations defining photon, population inversion and absorption centres densities are numerically solved being the basis of passively optical Q-switched laser functional simulation. The numerical simulations are performed using the several software packages, mostly SCILAB programs. The developed SCILAB programs can be used for a large range of saturable absorption centre and active media parameters, mainly the initial (low signal) optical transmittance of the passive optical Q-switch. The developed FORTRAN and SCILAB programs can be applied for passively Q-switched solid state lasers of several types emitting at several NIR wavelengths, in domain 1 ÷ 2 μm. For validating the numerical simulation results are compared with The results of the numerical simulation are compared with experimentally obtained ones, in the case of a LiF:F2 passively Q-switched Nd:YAG. A good agreement between the two kinds of results is observed.

Valuing changes in forest biodiversity

The paper attempts to improve current understanding of the economic value of biodiversity. Instead of the prevailing approach of using only one indicator of biodiversity (typically, species richness) we provide evidence that it is possible to value changes in a number of attributes which describe complex characteristics of biodiversity, based on ecological knowledge. The attributes used include structural, species and functional diversity. The empirical application is a choice experiment study conducted in the Białowieża Forest, Poland: our study is therefore also one of the first to cast light on the value of biodiversity protection in Eastern Europe. Interestingly, respondents valued passive protection regimes resulting in preservation of natural ecological processes. In addition, the respondents seemed to be concerned with the means, and not only the results of protection programmes.

Diode-end-pumped passively Q-switched 1.34 μm Nd:Gd 0.5Y 0.5VO 4 laser with Co 2+:LMA saturable absorber

In this paper, the output performances at 1.34 μm in continuous wave operation and passive Q-switching regime of a diode-end-pumped Nd:Gd 0.5Y 0.5VO 4 laser have been investigated. The passive Q-switching regime was achieved with Co 2+:LaMgAl 11O 19 (Co 2+:LMA) saturable absorbers crystals. A maximum average output power of 230 mW was recorded with a Co 2+:LMA with initial transmission of 81%. The minimum pulse duration was 116 ns, which corresponded to a repetition rate of 360 kHz, the single pulse energy of 2.1 μJ and the pulse peak power of 5.5 W.

CW and passive Q-switching of 1331-nm Nd:GGG laser with Co2+:LMA saturable absorber

In this paper, the output performances at 1331 nm in continuous-wave (CW) operation and the passive Q-switching regime of a Nd:Gd3Ga5O12(Nd:GGG) laser crystal have been investigated under pumping with diode lasers. A maximum CW output power of 1.5 W was reached at an incident pump power of 7.5 W; the overall optical-to-optical efficiency and the slope efficiency with respect to the pump power were 21.5% and 19.4%, respectively. The passive Q-switching regime was achieved with Co2+:LaMgAl11O19 (Co2+:LMA) saturable absorber (SA) crystals. A maximum average output power of 183 mW was recorded with a Co2+:LMA SA with initial transmission Ti of 90%. The pulse energy was 18.7 μJ and the pulse duration was 26.1 ns, which correspond to a pulse peak power of 0.7 kW. With a Co2+:LMA SA with Ti=81%, the average power decreased to 131 mW. However, the pulse energy increased to 21.4 μJ, the pulse duration was 16.4 ns and the pulse peak power increased to 1.3 kW.

Genotoxic effects of vehicle traffic pollution as evaluated by micronuclei test in tradescantia (Trad-MCN)

The quality of life in large urban centers is directly affected by the air quality there. Atmospheric monitoring is therefore imperative, and bioassays using plant models to detect the effects of genotoxic agents are recognized as giving excellent results. The present study utilized Trad-MCN to evaluate the genotoxic effects of atmospheric pollutants in the city of Feira de Santana, Bahia State, Brazil, in three locations with varying traffic loads. Inflorescences were collected on a monthly basis from plants growing in these locations in both passive and active monitoring regimes. The occurrence of micronuclei (MCN) was found to be proportional to vehicular flux under both monitoring regimes; with the plants being accompanied by active monitoring demonstrating the greatest sensitivity to atmospheric contamination. The results indicated that locations with the most intense vehicular traffic demonstrated significant atmospheric contamination by pollutants able to damage DNA.

Soil Genesis and Development, Lesson 3: Soil Forming Factors

This lesson explores the five major factors of soil formation—(1) climate, (2) organisms, (3) time, (4) topography, and (5) parent material—and their influence in forming soil. The distinction between active and passive factors, moisture and temperature regimes, organism and topographic influences, and parent material sources are described.

Bayesian Analysis of DSGE Models with Regime Switching

I estimate DSGE models with recurring regime changes in monetary policy (inflation target and reaction coefficients), technology (growth rate and volatility), and/or nominal price rigidities. In the models, agents are assumed to know deep parameter values but make probabilistic inference about prevailing and future regimes based on Bayes’ rule. I develop an estimation method that takes these probabilistic inferences into account when relating state variables to observed data. In an application to postwar U.S. data, I find stronger support for regime switching in monetary policy than in technology or nominal rigidities. In addition, a model with regime switching policy that conforms to the long-run Taylor principle given in Davig and Leeper (2007) is preferred to a determinacy-indeterminacy model motivated by Lubik and Schorfheide (2004). These empirical results indicate that, even though a passive policy regime produced more volatility in the economy from the early 1970s to the mid-1980s, the economy can be explained by determinacy over the entire postwar period, implying no role for sunspot shocks in explaining the changes in volatility.

Erbium-glass slab laser with transverse diode pumping

A slab laser based on borosilicate phosphate glass doped with erbium and ytterbium with transverse diode pumping has been developed and investigated. In the passive Q-switching regime, using a shutter based on a glass-crystalline material with nanosize spinel doped with divalent cobalt ions, the energy of the output radiation was 1.3mJ with a pulse width of 19ns. With active Q switching, the energy of the developed laser was 2.3mJ. The internal optical losses are estimated, and the parameters of the passive shutter are determined.

Neuromuscular Fatigue and Recovery in Elite Female Soccer

To investigate the time course of recovery from neuromuscular fatigue and some biochemical changes between two female soccer matches separated by an active or passive recovery regime. Countermovement jump (CMJ), sprint performance, maximal isokinetic knee flexion and extension, creatine kinase (CK), urea, uric acid, and perceived muscle soreness were measured in 17 elite female soccer players before, immediately after, 5, 21, 45, 51, and 69 h after a first match, and immediately after a second match. Eight players performed active recovery (submaximal cycling at 60% of HRpeak and low-intensity resistance training at < 50% 1RM) 22 and 46 h after the first match. In response to the first match, a significant decrease in sprint performance (-3.0 +/- 0.5%), CMJ (-4.4 +/- 0.8%), peak torque in knee extension (-7.1 +/- 1.9%) and flexion (-9.4 +/- 1.8%), and an increase in CK (+ 152 +/- 28%), urea (15 +/- 2), uric acid (+ 11 +/- 2%), and muscle soreness occurred. Sprint ability was first to return to baseline (5 h) followed by urea and uric acid (21 h), isokinetic knee extension (27 h) and flexion (51 h), CK, and muscle soreness (69 h), whereas CMJ was still reduced at the beginning of the second match. There were no significant differences in the recovery pattern between the active and passive recovery groups. The magnitude of the neuromuscular and biochemical changes after the second match was similar to that observed after the first match. The present study reveals differences in the recovery pattern of the various neuromuscular and biochemical parameters in response to a female soccer match. The active recovery had no effects on the recovery pattern of the four neuromuscular and three biochemical parameters.

Mechanism for clarifying YAG:V^3+ passive laser shutters accompanying SRS conversion in KGW:Nd^3+ crystals

This paper shows that it is necessary to take into account the orientation of the electric field vector of the generated light wave relative to the crystallographic axes of laser shutters when they are being developed and operated. The results show how the lasing efficiency of a Raman laser with polarized radiation in the passive Q-switched regime depends on the orientation of the electric field vector of the generated light wave relative to the crystallographic axes of laser shutters made from a YAG:V3+ crystal.

Understanding the New Keynesian Model When Monetary Policy Switches Regimes

This paper studies a New Keynesian model in which monetary policy may switch between regimes. We derive sufficient conditions for indeterminacy that are easy to implement and we show that the necessary and sufficient condition for determinacy, provided by Davig and Leeper, is necessary but not sufficient. More importantly, we use a two-regime model to show that indeterminacy in a passive regime may spill over to an active regime no matter how active the latter regime is. As a result, a passive monetary policy is more damaging than has been previously thought. Our results imply that the propagation of shocks in an active regime, such as that of the Federal Reserve in the post-1982 period, may be substantially affected by the possibility of a return to a passive regime of the kind that was followed in the 1960s and 1970s.

Passive Q-switching of an erbium-doped glass laser by using a Co2+ : ZnSe crystal

The operation of a passively Q-switched laser emitting the TEMmn mode is described. The excited-state absorption losses and nonlinear absorption in the shaded ends of the active element are taken into account. We measured the laser pulse energy for the TEM00 mode, the ratios of the output energy in transverse TEMmn modes with m = 0–4, n = 0 and m = 0–3, n = 1 to the TEM00 mode energy in an erbium-doped glass laser and determined its temporal parameters in the passive Q-switching regime achieved with the help of a Co2+ : ZnSe crystal. It is shown that on passing from one type of the transverse mode to another for invariable parameters of the resonator, the laser pulse energy changes discretely. A change in the radius of the transverse distribution of the TEM00 mode at the output mirror of the passively Q-switched laser during the development of lasing is estimated. It is found that the relative change in the laser beam cross section on the output mirror under our conditions is less than 2%. The experimental data obtained in the study are in good agreement with our calculations.