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Sample records for aquic regimes

  1. Dynamics of Soil and Grain Micronutrients as Affected by Long-Term Fertilization in an Aquic Inceptisol

    Institute of Scientific and Technical Information of China (English)

    LI Ben-Yin; HUANG Shao-Min; WEI Ming-Bao; H.L.ZHANG; SHEN A-Lin; XU Jian-Ming; RUAN Xin-Ling

    2010-01-01

    Micronutrient status in soils can be affected by long-term fertilization and intensive cropping.A 19-year experiment (1990-2008) was carried out to investigate the influence of different fertilization regimes on micronutrients in an Aquic Inceptisol and maize and wheat grains in Zhengzhou,China.The results showed that soil total Cu and Zn markedly declined after 19 years with application of N fertilizer alone.Soil total Fe and Mn were significantly increased mainly due to atmospheric deposition.Applications of P and organic fertilizer with incorporation of straws resulted in dramatic increases in soil total Cu,Zn,Fe,and Mn.Soil diethylenetriamine pentaacetic acid (DTPA)-extractable Cu in all treatments sharply decreased from initially 1.12 to about 0.8 mg kg-1.The treatments with organic fertilizer had the highest soil DTPA-extractable Cu,Zn,Fe,and Mn after 19 years of cropping and fertilization,thus demonstrating the important role of organic fertilizer application in improving available micronutrient status.Cu and Zn contents in wheat grains in the no-P treatments were significantly higher than those of the treatments with P application.In addition,Fe and Mn contents in wheat grains were positively correlated with their soil DTPA-extractable concentrations.These indicated that the long-term application of organic fertilizer resulted in significant increases in soil total and available micronutrient concentrations and remarkable reduction in wheat grain Cu and Zn contents,which was due to high soil available P.

  2. K+ Adsorption Kinetics of Fluvo-Aquic and Cinnamon Soil Under DifferentTemperature

    Institute of Scientific and Technical Information of China (English)

    LONGHuai-yu; LIYun-zhu; ZHANGWei-li; JIANGYi-chao

    2004-01-01

    The K+ adsorption kinetics of fluvo-aquic soil and cinnamon soil under different temperatures were studied. The results showed: 1) The first order equations were the most suitable for fitting the adsorption under various temperature levels with constant K+ concentration in displacing fluid. With temperature increasing, the fitness of Elovich equation increased,while those of power equation and parabolic diffusion equation decreased; 2)the apparent adsorption rate constant ka and the product of ka multiplied by the apparent equilibrium adsorption q∞ increased when temperature increased, while the apparent equilibrium adsorption q∞reduced; 3)temperature influenced hardly the reaction order, the order of concentration and adsorpton site were always 1 under various temperatures, if they were taken into account simultaneously, the adsorption should be a two-order reaction process; 4)the Gibbs free energy change A G of potassium adsorption were negative, ranged from -4 444.56to -2 450.63 Jmol-1,and increased with temperature increasing, while enthalpy change A H,entropy change A S, apparent adsorption activation Ea, adsorption activation energy E2 and desorption activation energy E2 were temperature-independent; 5)the adsorption was spontaneous process with heat releasing and entropy dropping, fluvo-aquic soil released more heat than cinnamon soil.

  3. K+ Adsorption Kinetics of Fluvo-Aquic and Cinnamon Soil Under Different Temperature

    Institute of Scientific and Technical Information of China (English)

    LONG Huai-yu; LI Yun-zhu; ZHANG Wei-li; JIANG Yi-chao

    2004-01-01

    The K+ adsorption kinetics of fluvo-aquic soil and cinnamon soil under different temperatures were studied. The results showed: 1) The first order equations were the most suitable for fitting the adsorption under various temperature levels with constant K+ concentration in displacing fluid. With temperature increasing, the fitness of Elovich equation increased,while those of power equation and parabolic diffusion equation decreased; 2)the apparent adsorption rate constant ka and the product of ka multiplied by the apparent equilibrium adsorption q. increased when temperature increased, while the apparent equilibrium adsorption q∞ reduced; 3)temperature influenced hardly the reaction order, the order of concentration and adsorpton site were always 1 under various temperatures, if they were taken into account simultaneously, the adsorption should be a two-order reaction process; 4)the Gibbs free energy change AG of potassium adsorption were negative, ranged from -4 444.56to -2 450.63 Jmol-1,and increased with temperature increasing, while enthalpy change △H,entropy change △ S, apparent adsorption activation Ea, adsorption activation energy E1and desorption activation energy E2 were temperature-independent; 5)the adsorption was spontaneous process with heat releasing and entropy dropping, fluvo-aquic soil releasedmore heat than cinnamon soil.

  4. [K fertility and K deficit index of aquic brown soil under different fertilization systems].

    Science.gov (United States)

    Yu, Wan-Tai; Jiang, Zi-Shao; Shen, Shan-Min; Zhang, Lu

    2007-10-01

    A 15-year fertilization experiment was conducted on an aquic brown soil to study the variations of its K fertility and the index of K deficit under different fertilization systems. The results indicated that no K application accelerated the depletion of soil K, representing a certain decrease of soil available and slow-release K. Applying K alone could not keep soil K in balance, still having a decrease of soil available and slow-release K. The application of recycled compost combined with appropriate amount of fertilizer K could compensate soil K expenditure to a certain degree, and keep the concentrations of soil available and slow-release K somewhat constant. The statistic analysis on the past years test results showed that the critical values of soil available K in corn- and soybean fields obtained by crossing method were all 73 mg x kg(-1). PMID:18163304

  5. Temporal Variability of Physical Properties on an Aquic Argiudoll under no Tillage

    Science.gov (United States)

    Castiglione, M. G.; Sasal, M. C.; Wilson, M. G.; Paz González, A.; Oszust, J. D.

    2012-04-01

    Practices for the implementation and development of crops affect soil properties and processes in space and time with consequences for the accumulation and movement of water, nutrients and pollutants, which affects plant growth. The aim of this study was to determine the temporal variability of soil physical properties and its link with the infiltration process, on an Aquic Argiudoll of the Argentine Pampas under no-till cultivation. Sampling was performed during six dates in the INTA EEA Paraná (Entre Ríos, Argentina), in the course of the succession of wheat/ soybean-corn. In each of those dates, rain simulations were performed under covered and uncovered soil. From these results it was determined the saturated hydraulic conductivity (Ks), the runoff coefficient (EC), the accumulated rainfall up to ponding (Tp), the accumulated rainfall to reach the steady state infiltration rate (TI) and the decline slope of the infiltration rate (Pd). Also we determine: the initial soil water content (HI), bulk density (Dap), volume occupied by pores larger than 50 µm (> 50), volume occupied by pores between 10 and 50 µm (10-50), soil physical quality index (S) and structural stability (CDMP). On three dates HI was approximately 11%, two were between 22 and 27% and in the remaining time HI was 36%. Despite these variations we don't observed significant changes in most soil physical properties associated with the structure and pore size. However, we could prove significant differences between dates in Ks and EC, both on bare and cover soil. At the same time, differences in these parameters between coverage degrees were significant only in two dates. The HI affected the variability of Ks results. Also Ks ratio between covered and uncovered soil improved with HI increment, except for HI equal to 36%. We found highly significant linkage between Ks, CE and Pd with HI. This study reveals the importance of the temporal dynamics of water movement in this Aquic Argiudoll, although

  6. Vertical distribution of plant nematodes in an aquic brown soil under different land uses

    Institute of Scientific and Technical Information of China (English)

    MENG Fan-xiang; Liang Wen-ju; OU Wei; JIANG Yong; LI Qi; WEN Da-zhong

    2005-01-01

    The vertical distribution of the dominant genera of plant nematodes at the depth of 0-150 cm of an aquic brown soil were studied for four land use patterns, i.e., paddy field, maize field, fallow field and woodland in the Shenyang Experimental Station of Ecology, Chinese Academy of Sciences in November of 2003. The results showed that the numbers of some dominant genera under different land uses decreased with the increase of soil depth. Helicotylenchus was most dominant genus under each land use type. Genera of Filenchus, Psilenchus and Tylenchus in paddy field occurred at the depth of 0-20 cm; while Paratylenchus in fallow field and woodland, as well as Pratylenchus in maize field presented in the deeper soil layers (0-80 cm). Significant correlations between the numbers of dominant genera of plant nematodes and soil chemical properties were found in this study. The number of Helicotylenchus under different land uses was positively correlated with C/N ratio, total C, total N, total P, alkai-N, and Olsen-P. The numbers of Filenchus and Paratylenchus in paddy field, Pratylenchus in maize field and Paratylenchus in fallow field were negatively correlated with soil pH, and positively correlated with total C, total N and alkai-N. This study results showed that it is essential to sample at a certain depth according to the vertical distribution information of different genera of plant nematodes in adequately assessing the population size of plant nematodes.

  7. Effect of Continuous Vegetable Cultivation on Phosphorus Levels of Fluvo-Aquic Soils

    Institute of Scientific and Technical Information of China (English)

    WANG Xin-Min; HOU Yan-Lin

    2004-01-01

    Soil P status, inorganic P fractions, and P sorption properties were studied using sandy fluvo-aquic horticultural soils,which are high in organic matter content for vegetable production in comparison with a soil used for grain crop production in Zhengzhou, Henan Province, China. P fractions, Olsen-P, and OM were determined at different depths in the soil profile and sorption isotherm experiments were performed. Most P in excess of plant requirements accumulated in the topsoil and decreased with soil depth. Total P, inorganic P, and OM concentrations increased with continued horticultural use. Olsen-P concentrations in the 0-20 cm depth of horticultural soils were 9 to 25 times higher than those of the grain crop soil. A linear transformation of the Langmuir equation showed that the P adsorption maximum (491.3 mg P kg-i)and the maximum phosphate buffering capacity (162.1 L kg-1) for 80-100 cm were greater in the grain crop soil than the horticultural soils. Thus, the most immediate concern with excess P were in areas where heavy P fertilizer was used for vegetable crops and where soil P sorption capacities were low due to sandy soils and high organic matter content.

  8. Hidromorfía y condiciones ácuicas en suelos de la llanura aluvial de Tucumán (Argentina Hydromorphy and aquic conditions in soils of the alluvial plain of Tucumán (Argentina

    Directory of Open Access Journals (Sweden)

    Rodolfo Oscar Zappino

    2010-07-01

    micromorphological scale. In the well-drained and moderately well-drained profiles, Fe d and Mn d show little mobility, with the respective values ranging from 0.50-0.80% and 0.03-0.06%, Mn d / Fe d <0.08% and underdeveloped redoximorphic features. In the profiles with imperfect drainage, the Fe d sometimes co-migrates with and sometimes separates from clay, with the segregation of Fe d outside the profile. Mn d has low values (0.01-0.06% with an increase of 0.20% in the BC of La Fronterita X, Mn/Fe d = 0.33 and more developed redox features. The analysis suggests that the hydromorphic process increases from the moderately well-drained La Fronterita XI profile towards the imperfectly drained La Fronterita X and Famaillá profiles. The former two profiles are expressed in the Mn/Fe d ratio and in the increasing size and abundance of redox features as observed on a micromorphological scale; and the Famaillá profile in the low mean value of Fe d and Mn, and the presence of redoximorphic features. The Fronterita X and Famaillá profiles present the most reduced conditions among the studied soils and are assumed to conform to an aquic regime.

  9. Long-term organic and inorganic fertilizations enhanced basic soil productivity in a lfuvo-aquic soil

    Institute of Scientific and Technical Information of China (English)

    ZHA Yan; WU Xue-ping; GONG Fu-fei; XU Ming-gang; ZHANG Hui-min; CHEN Li-ming; HUANG Shao-min; CAI Dian-xiong

    2015-01-01

    The improvement of soil productivity depends on a rational input of water and nutrients, optimal ifeld management, and the increase of basic soil productivity (BSP). In this study, BSP is deifned as the productive capacity of a farmland soil with its own physical and chemical properties for a speciifc crop season under local ifeld management. Based on 19-yr data of the long-term agronomic experiments (1989–2008) on a lfuvo-aquic soil in Zhengzhou, Henan Province, China, the decision support system for agrotechnology transfer (DSSAT ver. 4.0) crop growth model was used to simulate yields by BSP of winter wheat (Triticum aestiviumL.) and summer maize (Zea maysL.) to examine the relationship between BSP and soil organic carbon (SOC) under long-term fertilization. Five treatments were included: (1) no fertilization (control), (2) nitrogen, phosphorus and potassium fertilizers (NPK), (3) NPK plus manure (NPKM), (4) 1.5 times of NPKM (1.5NPKM), and (5) NPK plus straw (NPKS). After 19 yr of treatments, the SOC stock increased 16.7, 44.2, 69.9, and 25.2% under the NPK, NPKM, 1.5NPKM, and NPKS, respectively, compared to the initial value. Among various nutrient factors affecting contribution per-centage of BSP to winter wheat and summer maize, SOC was a major affecting factor for BSP in the lfuvo-aquic soil. There were signiifcant positive correlations between SOC stock and yields by BSP of winter wheat and summer maize (P<0.01), and yields by BSP of winter wheat and summer maize increased 154 and 132 kg ha–1 when SOC stock increased 1 t C ha–1. Thus, increased SOC accumulation is a crucial way for increasing BSP in lfuvo-aquic soil.The manure or straw combined application with chemical fertilizers signiifcantly enhanced BSP compared to the application of chemical fertilizers alone.

  10. Atrazine Adsorption Behavior on a Fluvo-Aquic Soil as Influenced by Contact Periods

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A batch experiment was performed to investigate nonequilibrium adsorption behavior of atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) on a fluvo-aquic soil. The amount of atrazine sorbed increased with increasing adsorption contact periods. For a range of initial atrazine concentrations, the percentage of atrazine sorbed within 24 h ranged from 24% to 77% of the observed total amount sorbed for the longest contact period; when adsorption contact periods were more than 72 h, the deviations in curves fitted using a nonlinear Freundlich equation gradually became less. The opposite trend was observed for the atrazine concentrations in solution. The effect of adsorption contact periods on atrazine adsorption behavior was evaluated by interpreting the temporal variations in linear and nonlinear Freundlich equation parameters obtained from the phase-distribution relationships. As the adsorption contact period increased, the nonlinear Freundlich capacity coefficient kf showed a significant linear increase (r2 = 0.9063, P < 0.001). However, a significant negative linear correlation was observed for the nonlinear coefficient n, a dimensionless parameter (r2 = 0.5666,P < 0.05).Furthermore, the linear distribution coefficient kd ranged from 0.38 to 1.44 and exhibited a significant linear correlation to the adsorption contact period (r2 = 0.72, P < 0.01). The parameters k f and n obtained from a time-dependent isotherm rather than the distribution coefficient kd estimated using the linear Freundlich equation were more appropriate to predict the herbicide residue in the field and thus more meaningful for environmental assessment.

  11. Vertical variation and storage of nitrogen in an aquic brown soil under different land uses

    Institute of Scientific and Technical Information of China (English)

    ZHANGYu-ge; JIANGYong; LIANGWen-ju; WENDa-zhong; ZHANGYu-long

    2004-01-01

    The vertical variation and storage of nitrogen in the depth of 0-150 cm of an aquic brown soil were studied under 14 years of four land use patterns, i.e., paddy field, maize field, fallow field and woodland in Shenyang Experimental Station of Ecology, Chinese Academy of Sciences in November of 2003. The results showed that different land uses had different profile distributions of soil total nitrogen (STN), alkali N, ammonium (NH4+-N) and nitrate (NO3-N). The sequence of STN storage was woodland >maize field > fallow field > paddy field, while that of NO3--N content was maize field > paddy field > woodland > fallow field, suggesting the different root biomass and biological N cycling under various land uses. The STN storage in the depth of 0-100 cm of woodland averaged to 11.41 t. hm1, being 1.65 and 1.25 times as much as that in paddy and maize fields, respectively, while there was no significant difference between maize and fallow fields. The comparatively higher amount of NO3--N in maize and paddy fields may be due to nitrogen fertilization and anthropogenic disturbance. Soil alkali N was significantly related with STN, and the correlation could be expressed by a linear regression model under each land use (/:/2>0.929, p<0.001 ). Such a correlation was slightly closer in nature (woodland and fallow field) than in agro ecosystems (paddy and maize fields). Heavy N fertilization induced an excess of crop need, and led to a comparatively higher amount of soil NO3-N in cultivated fields than in fallow field and woodland. It is suggested that agroforestry practices have the potential to make a significant contribution to both crop production and environment protection.

  12. Characteristics of Magnesium Release from Fluvo-Aquic Soil and Relative Availability of Magnesium to Plants

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Experiments including two in laboratory and one in greenhouse were carried out to study non-exchange able magnesium release from fluvo-aquic soils sampled from Daxing and Changping counties located in the suburbs of Beijing and Mg relative availability of the two soils to plants. In a batch experiment in laboratory the soils were incubated under wet conditions and alternation of dry and wet conditions and determined for amount of Mg released at the 4th, 8th and 12th week, respectively, after extraction of exchangeable Mg with 1 mol L-1 NH4Ac. The amount of Mg released from the soil of Daxing was higher than from the soil of Changping, which was in accordance with the fact that the soil of Daxing had higher contents of all forms of Mg than that of Changping. There was little difference in Mg release from soils between wet conditions and alternation of dry and wet conditions. About 1%~2% of the total non-exchangeable Mg might be released within 12 weeks of incubation, restoring about 30%~35% of the original soil exchangeable Mg. Results of the experiment on kinetics of Mg release from the soils through continuous extractions with 0.5 mol L-1 NH4Ac (pH 7.0) on a continuous flow apparatus in laboratory showed that Mg released rapidly in the beginning, decreased sharply with time and kept stable at 60 and 240 rain for the soils of Changping and Daxing, respectively. Among the five mathematical models used to describe the kinetics of Mg release, the parabolic diffusion equation best fitted the cumulative Mg release, indicating that diffusion of Mg out of the soils might be the controlling process. The experiment of exhaustive cropping with 1 crop of tomato (Lycopersicon esculentum Mill.) followed by six crops of corn (Zea mays L.) in greenhouse showed that soil exchangeable Mg decreased remarkably with cropping. After three crops, the percentage of the total plant Mg uptake that came from soil non-exchangeable Mg was 29.5% for the soil from Changping and 35% for the

  13. Crop Yield, N Uptake and Nitrates in a Fluvo-Aquic Soil Profile

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shu-Xiang; LI Xiu-Ying; LI Xiao-Ping; YUAN Feng-Ming; YAO Zhao-Hua; SUN Yong-Lin; ZHANG Fu-Dao

    2004-01-01

    The effects of different chemical fertilizer combinations (N, P and K) on crop yield, N uptake and nitrate distribution and accumulation to a depth of 100 cm were studied in a cinnamon fiuvo-aquic soil profile (Beijing) with a continuous winter wheat-summer maize cropping system for nine years. The experiment consisted of 7 treatments: no fertilizer control (CK); N alone, N in combination with K (NK), P (NP), and P and K (NPK and N1PK); and P and K in combination without N (PK). The rate of N was 150 kg ha-1 for the N treatments except Treatment N1PK with higher N rate (195 kg ha-1), and the rates of P (P2O5) and K (K2O) were 75 and 37.5 kg ha-1, respectively. The applications of N combined with P and K (NK, NP and NPK) resulted in higher crop yields than a single application of N. The yields followed the order: NPK >NP > N1PK > PK > NK > N > CK for winter wheat, and NPK > N1PK > NP > NK > N > PK > CK for summer maize. Supplement of N with P or K, or both P and K resulted in a higher average N uptake of the two crops, which was in a decreasing order NPK > NP > N1PK > NK > N > PK > CK. The combinations also increased apparent N recovery more than N alone and CK. The nitrate content in the profile was thus reduced more in the combination treatments. The nitrate accumulation in the soil profiles followed the order:N > NK > N1PK > NPK > NP > CK > PK. Higher N uptake by the adequately fertilized crops (Treatment NPK) reduced nitrate accumulation in the profile and thus reduced nitrate leaching. The optimum N:P:K ratio was thus of paramount importance in increasing yields and N uptake of crops and reducing nitrate leaching losses.

  14. Using magnetic susceptibility to discriminate between soil moisture regimes in selected loess and loess-like soils in northern Iran

    Science.gov (United States)

    Valaee, Morteza; Ayoubi, Shamsollah; Khormali, Farhad; Lu, Sheng Gao; Karimzadeh, Hamid Reza

    2016-04-01

    This study used discriminant analysis to determine the efficacy of magnetic measures for discriminating between four soil moisture regimes in northern Iran. The study area was located on loess deposits and loess-like soils containing similar parent material. Four soil moisture regimes including aridic, xeric, udic, and aquic were selected. A total of 25 soil profiles were drug from each regime and composite soil samples were collected within the moisture control section. A set of magnetic measures including magnetic susceptibility at low (χlf) and high (χhf) frequencies, frequency-dependent magnetic susceptibility (χfd), saturation isothermal remnant magnetization (SIRM), and isothermal remnant magnetization (IRM100 mT, IRM 20 mT) were measured in the laboratory. Dithionite citrate bicarbonate (Fed) and acid oxalate (Feo) contents of all soil samples were also determined. The lowest and highest χlf and χhf were observed in aquic and udic moisture regimes, respectively. A similar trend was obtained for Fed and Fed-Feo. The significant positive correlation between Fed and SIRM (r = 0.60; P SSD) due to pedogenic processes. The results of discriminant analysis indicated that a combination of magnetic measures could successfully discriminate between the selected moisture regimes in the study area (average accuracy = 80%). It can thus be concluded that magnetic measures could be applied as a powerful indicator for differentiation of soil moisture regimes in the study area.

  15. Using magnetic susceptibility to discriminate between soil moisture regimes in selected loess and loess-like soils in northern Iran

    Science.gov (United States)

    Valaee, Morteza; Ayoubi, Shamsollah; Khormali, Farhad; Lu, Sheng Gao; Karimzadeh, Hamid Reza

    2016-04-01

    This study used discriminant analysis to determine the efficacy of magnetic measures for discriminating between four soil moisture regimes in northern Iran. The study area was located on loess deposits and loess-like soils containing similar parent material. Four soil moisture regimes including aridic, xeric, udic, and aquic were selected. A total of 25 soil profiles were drug from each regime and composite soil samples were collected within the moisture control section. A set of magnetic measures including magnetic susceptibility at low (χlf) and high (χhf) frequencies, frequency-dependent magnetic susceptibility (χfd), saturation isothermal remnant magnetization (SIRM), and isothermal remnant magnetization (IRM100 mT, IRM 20 mT) were measured in the laboratory. Dithionite citrate bicarbonate (Fed) and acid oxalate (Feo) contents of all soil samples were also determined. The lowest and highest χlf and χhf were observed in aquic and udic moisture regimes, respectively. A similar trend was obtained for Fed and Fed-Feo. The significant positive correlation between Fed and SIRM (r = 0.60; P < 0.01) suggested the formation of stable single domains (SSD) due to pedogenic processes. The results of discriminant analysis indicated that a combination of magnetic measures could successfully discriminate between the selected moisture regimes in the study area (average accuracy = 80%). It can thus be concluded that magnetic measures could be applied as a powerful indicator for differentiation of soil moisture regimes in the study area.

  16. Acid and Alkali Buffer Capacity of Typical Fluvor-Aquic Soil in Huang-HuaiHai Plain

    Institute of Scientific and Technical Information of China (English)

    HUANG Ping; ZHANG Jia-bao; ZHU An-ning; ZHANG Cong-zhi

    2009-01-01

    Soil acid and alkali buffer capacity, as a major indicator for evaluating its vulnerability and resistibility to acidification and alkalization, is an important factor affecting the sustainable agriculture, through knowledge on which soil acidification process can be predicted and modified. In this study, titration curve method was adopted to investigate the pH buffer capacity (pHBC) of fluvor-aquic soil, and separate titration curves were established by adding incremental amounts of either standardized hydrochloric acid (HCl) (0.12 mol L-1) or sodium hydroxide (NaOH) (0.10 mol L-1) to soil suspended in deionized water (soil:solution=1:5). Soil pH was measured after 7 d resuspension and isothermal equilibrium (T= 25℃). Linear regressions were fitted to the linear portion of each titration curve and the slopes of these lines were derived as the soil pHBC. The results showed that significant correlations between the amounts of adding acid or alkali and each pH change were presented, and titration curve method was feasible for measurement of pHBC on typical fluvor-aquic soil in Huang-Huai-Hai Plain, and the coefficients of determination were higher than the similar researches on acid soil (R2= 0.96). The slope-derived pHBC of acid and alkali were 158.71 and 25.02 mmol kg-1, respectively. According to the classification of soil buffer systems, the soil tested belongs to the calcium carbonate buffer system, carbonates contribute the most to pHBC, and the contribution of soil organic matter relatively less than it.

  17. Effects of slow-release urea fertilizers on urease activity, microbial biomass, and nematode communities in an aquic brown soil.

    Science.gov (United States)

    Jiao, Xiaoguang; Liang, Wenju; Chen, Lijun; Zhang, Haijun; Li, Qi; Wang, Peng; Wen, Dazhong

    2005-05-01

    A field experiment was carried out at the Shenyang Experimental Station of Ecology (CAS) in order to study the effects of slow-release urea fertilizers high polymer-coated urea (SRU1), SRU1 mixed with dicyandiamide DCD (SRU2), and SRU1 mixed with calcium carbide CaC2 (SRU3) on urease activity, microbial biomass C and N, and nematode communities in an aquic brown soil during the maize growth period. The results demonstrated that the application of slow-release urea fertilizers inhibits soil urease activity and increases the soil NH4+-N content. Soil available N increment could promote its immobilization by microorganisms. Determination of soil microbial biomass N indicated that a combined application of coated urea and nitrification inhibitors increased the soil active N pool. The population of predators/omnivores indicated that treatment with SRU2 could provide enough soil NH4+-N to promote maize growth and increased the food resource for the soil fauna compared with the other treatments.

  18. Macroeconomic regimes

    NARCIS (Netherlands)

    Baele, L.T.M.; Bekaert, G.R.J.; Cho, S.; Inghelbrecht, K.; Moreno, A.

    2015-01-01

    A New-Keynesian macro-model is estimated accommodating regime-switching behavior in monetary policy and macro-shocks. A key to our estimation strategy is the use of survey-based expectations for inflation and output. Output and inflation shocks shift to the low volatility regime around 1985 and 1990

  19. Losses of Urea—Nitrogen Applied to Maize Grown on a Calcareous Fluvo—Aquic Soil in North China Plain

    Institute of Scientific and Technical Information of China (English)

    ZHANGSHAO-LIN; ZHUZHAO-LIANG; 等

    1992-01-01

    Field experiments were conducted in a maize (Zea mays L.)field of a calcareous fluvo-aquic soil in North China Plain for studying the fate and ammonia loss of urea-N applied at seedling stage,as well as the effectiveness of coated calcium carbide(CCC) in reducing N loss and in improving the yield efficiency of urea.Results show that:(1) For the surface-broadcast treatment ammonia volatilization (measured with micro-meteorological technique)took place quickly,reached the peak 20-26hr after application,and then declined gradually;the cumulative ammonia loss approached the maximum 188hr after application (30% of the N applied),and increased only to 32% 284 hr after application;the latter accounted for 71% of the total loss (45% of applied N).(2) In the case of point placement at a depth of 5-10 cm,ammonia loss 188hr after application was only 12% of the N applied,accounting for 40% of the total loss.(3) There was no difference in total loss between the application depths of 6cm and 10 cm,the loss of them was 30% and 29%,respectively.(4) Total loss of N applied at lower rate (40kg N/ha)with point deep placement at 6cm depth was found only 4% of the N applied,it rose up to 30% when the rate of application increased to 80kg N/ ha.(5) The nitrification inhibitor,CCC,seemed to enhance N loss of urea rather than reduce it,and did not show any benefit effect in improving the yield efficiency of urea,which is presumably due to the high potential of ammonia volatilization in the soil and climatic conditions under investigation.

  20. Activity and Composition of Ammonia-Oxidizing Bacteria in an Aquic Brown Soil as Influenced by Land Use and Fertilization

    Institute of Scientific and Technical Information of China (English)

    YU Wan-Tai; XU Yong-Gang; BI Ming-Li; MA Qiang; ZHOU Hua

    2010-01-01

    The effects of long-term(19 years)different land use and fertilization on activity and composition of ammonia-oxidizing bacteria(AOB)in an aquic brown soil were investigated in a field experiment in Liaoning Province,China.The 19-year experiment conducted from 1990 to 2008 involved seven treatments designed: cropping rotation of soybean-corn-corn with no fertilizer(control,CK),recycled manure(RM),fertilizer nitrogen(N),phosphorous(P)and potassium(K)(NPK),NPK+RM,and no-crop bare land,mowed fallow,and non-mowed fallow.The results showed that the potential nitrification rates of the RM,NPK+RM,mowed fallow,and non-mowed fallow treatments were significantly higher(P < 0.05)than those of the CK and NPK treatments,indicating that the long-term applications of recycled manure and return of plant residues both significantly increased the activity of AOB.Although the application of NPK did not enhance soil potential nitrification because of decreased pH,available K had an important effect on potential nitrification.Denaturing gradient gel electrophoresis(DGGE)fingerprint profiles showed that no-crop treatments had an increase in the diversity of the AOB community compared to the CK,RM,and NPK treatments,implying that agricultural practices,especially tillage,had an adverse effect on the soil AOB community.The NPK+RM treatment had the most diverse DGGE patterns possibly because of the increased available P in this treatment.A phylogenetic analysis showed that most of the DGGE bands derived belonged to Nitrosoxpira cluster 3,not Nitrosospira cluster 2.These demonstrated that different land use and fertilization significantly influenced the activity and composition of the AOB community by altering the soil properties,mainly including pH,total C,available K,and available P.

  1. Fate of Fertilizer Nitrogen Applied to Crops Grown on Fluvo—Aquic Soil in Huang—Huai—Hai Plain

    Institute of Scientific and Technical Information of China (English)

    WANGXIAN-ZHONG; ZHANGSHAO-LIN; 等

    1991-01-01

    The fate of urea-and ammonium bicarbonate(ABC)-nitrogen (N) applied by prevailing traditional techniques to winter wheat (Triticum aestivum L.)or maize (Zea mays L.)grown in the fields of Fluvo-aquic soil was investigated using 15N tracer-micro-plot technique.Results show that:(1) at maturity of wheat,N recovery in plants and N losses of urea and ABC applied at seeding in autumn were 31-39%,and 34-46%,respextively,while the corresponding figures for side-banding at 10 cm depth in early spring were 51-57%,and 5-12%;surface-broadcast of urea followed by irrigation at early spring was as efficient as the side-banding in improving N recovery in plants and reducing N loss,however,such techuique was found less satisfactory with ABC.(2)At the maturity of maize,N recovery in the plants and N loss of urea and ABC sidebanded at seedling stage or prior to tasseling ranged from 23% to 57%,and 9% to 26%,respectively.(3) Either in Wheat or in maize experiment,the majority of residual fertilizer N in soil profile (0-60cm) was in the form of biologically immobilized organic N,however,the contribution of ammonium fixation by clay minerals increased markedly nwith depth in soil profile.(4) Though the proportion of residual fertilizer N was generally highest in the top 20 cm soil layer,considerable reaidual N (nostly 6-11% of the N applied)was found in 60-100 cm soil layers.

  2. Long-term fertilization of organic manure led to the succession of Bacillus community in an alluvial-aquic soil

    Science.gov (United States)

    Chen, Ruirui; Lin, Xiangui; Feng, Youzhi; Hu, Junli; Wang, Ruirui

    2014-05-01

    Long-term fertilization inevitably influences soil physic-chemical and biological properties. Our previous studies with a long-term fertilization experiment on an alluvial-aquic have revealed that specific Bacillus spp. was observed in organic manure-fertilized soils. The current study investigated the effects of long-term fertilization on the succession of Bacillus community in soils and their functions. The experiment included three fertilizer treatments: organic manure (OM), mineral fertilizers (NPK) and the control (without fertilizers). The results showed that long-term application of chemical fertilizers didn't increase the quantity of soil microbial population as much as organic fertilizers did, but it played an important role in maintaining the diversity and community structure of indigenous Bacilli. Correspondingly, long-term application of organic manure significantly increased the quantity while significantly decreased the diversity of Bacilli community. The ratio of Bacilli/bacteria was more constant in OM treatment than NPK indicating the stability of the response to long-term organic fertilizers. PCR-DGGE and clone library revealed the succession of Bacillus community after long-term application of organic manure and the dominant Bacillus spp occurred in the treatmen OM was Bacillus asahii. Our results also proved that Bacillus asahii was not derived from exogenous organic manure, but one of indigenous bacteria in the soil. Bacillus asahii was induced by the substrate after the application of organic manure, and gradually evolved into dominant Bacillus after 4 to 5 years. With an enzyme assay test of pure species and a soil incubation experiment, we came to a preliminary judgment, that the dominant Bacillus asahii didn't significantly influence the decomposition rate of cellulose and protein in the soil, but it promoted the decomposition of lipids, and could also improve the transformation process from fresh organic matter to humus. Applied organic

  3. Regime change?

    International Nuclear Information System (INIS)

    Following the 1998 nuclear tests in South Asia and later reinforced by revelations about North Korean and Iraqi nuclear activities, there has been growing concern about increasing proliferation dangers. At the same time, the prospects of radiological/nuclear terrorism are seen to be rising - since 9/11, concern over a proliferation/terrorism nexus has never been higher. In the face of this growing danger, there are urgent calls for stronger measures to strengthen the current international nuclear nonproliferation regime, including recommendations to place civilian processing of weapon-useable material under multinational control. As well, there are calls for entirely new tools, including military options. As proliferation and terrorism concerns grow, the regime is under pressure and there is a temptation to consider fundamental changes to the regime. In this context, this paper will address the following: Do we need to change the regime centered on the Treaty on the Nonproliferation of Nuclear Weapons (NPT) and the International Atomic Energy Agency (IAEA)? What improvements could ensure it will be the foundation for the proliferation resistance and physical protection needed if nuclear power grows? What will make it a viable centerpiece of future nonproliferation and counterterrorism approaches?

  4. Competition Regime

    OpenAIRE

    Danilo Icaza Ortiz

    2013-01-01

    This paper is a review of the competition regime works of various authors, published under the auspices of the University of the Hemispheres and the Corporation for Studies and Publications. Analyzes the structure, the general concepts, case law taken for development. Includes comments on the usefulness of this work for the study of competition law and the contribution to the lawyers who want to practice in this branch of economic law.

  5. Competition Regime

    Directory of Open Access Journals (Sweden)

    Danilo Icaza Ortiz

    2013-01-01

    Full Text Available This paper is a review of the competition regime works of various authors, published under the auspices of the University of the Hemispheres and the Corporation for Studies and Publications. Analyzes the structure, the general concepts, case law taken for development. Includes comments on the usefulness of this work for the study of competition law and the contribution to the lawyers who want to practice in this branch of economic law.

  6. [Effects of long-term application of organic fertilizer and superphosphate on accumulation and leaching of Olsen-P in Fluvo-aquic soil].

    Science.gov (United States)

    Huang, Shao-Min; Guo, Dou-Dou; Zhang, Shui-Qing

    2011-01-01

    Based on a 20-year experiment of fertilization with organic and chemical fertilizers on a Fluvo-aquic soil under wheat-corn cropping system, this paper studied the relationships between Olsen-P concentration in plough layer and crop yields as well as the accumulation and vertical translocation of Olsen-P in soil profile. The results showed that when the Olsen-P concentration in plough layer maintained at 10-40 mg x kg(-1), the grain yields of wheat and corn were higher, whereas when the concentration of Olsen-P in plough layer was higher than 40 mg x kg(-1), it started to leach, which meant that in light loam Fluvo-aquic soil, the threshold value for P leaching might be 40 mg x kg(-1). In the treatments of chemical fertilization (NPK) and corn straw returning (SNPK) with the P application rate of 77-90 kg x hm(-2), the Olsen-P concentration in plough layer was increased by 0.63-0.72 mg x kg(-1) per 100 kg x hm(-2) of applied P, with an annual increment of 0.49-0.65 mg x kg(-1) and needed 45-60 years for reaching the threshold value for P leaching. In the treatments of chemical fertilization combined with manure application (MNPK, MNPK2, and 1.5MNPK), the formula of Olsen-P accumulation in 0-20 cm soil layer were Y(MNPK) = 3.1097x + 6.9615 (R2 = 0.8562), Y(MNPK2) = 2.4765x + 13.563 (R2 = 0.9307), and Y1.5MNPK = 4.506x + 6.4464 (R2 = 0.8862). It might take 8 years to reach the threshold value for Olsen-P leaching when the P application rate in treatment 1.5MNPK was 210 kg x hm(-2), 11 years when the P application rate in treatments MNPK2 and MNPK was 125 and 140 kg x hm(-2). Organic fertilization combined with chemical fertilization increased the Olsen-P accumulation rate being 2.5 times higher than chemical fertilization. Excessive application of organic fertilizer could increase the accumulation and leaching of Olsen-P in soil profile. PMID:21548294

  7. Characteristics of maize biochar with different pyrolysis temperatures and its effects on organic carbon, nitrogen and enzymatic activities after addition to fluvo-aquic soil.

    Science.gov (United States)

    Wang, Xiubin; Zhou, Wei; Liang, Guoqing; Song, Dali; Zhang, Xiaoya

    2015-12-15

    In this study, the characteristics of maize biochar produced at different pyrolysis temperatures (300, 450 and 600°C) and its effects on organic carbon, nitrogen and enzymatic activities after addition to fluvo-aquic soil were investigated. As pyrolysis temperature increased, ash content, pH, electrical conductivity, surface area, pore volume and aromatic carbon content of biochar increased while yield, ratios of oxygen:carbon and hydrogen: carbon and alkyl carbon content decreased. During incubation, SOC, total N, and ammonium-N contents increased in all biochar-amended treatments compared with the urea treatment; however, soil nitrate-N content first increased and then decreased with increasing pyrolysis temperature of the applied biochar. Extracellular enzyme activities associated with carbon transformation first increased and then decreased with biochars pyrolyzed at 450 and 600°C. Protease activity markedly increased with increased pyrolysis temperatures, whereas pyrolysis temperature had limited effect on soil urease activity. The results indicated that the responses of extracellular enzymes to biochar were dependent on the pyrolysis temperature, the enzyme itself and incubation time as well.

  8. Effects of slow-release urea fertilizers on urease activity,microbial biomass, and nematode communities in an aquic brown soil

    Institute of Scientific and Technical Information of China (English)

    JIAO; Xiaoguang; LIANG; Wenju; CHEN; Lijun; ZHANG; Haijun

    2005-01-01

    A field experiment was carried out at the Shenyang Experimental Station of Ecology (CAS) in order to study the effects of slow-release urea fertilizers high polymer-coated urea (SRU1), SRU1 mixed with dicyandiamide DCD (SRU2), and SRU1 mixed with calcium carbide CaC2 (SRU3) on urease activity, microbial biomass C and N, and nematode communities in an aquic brown soil during the maize growth period. The results demonstrated that the application of slow-release urea fertilizers inhibits soil urease activity and increases the soil NH4+-N content.Soil available N increment could promote its immobilization by microorganisms. Determination of soil microbial biomass N indicated that a combined application of coated urea and nitrification inhibitors increased the soil active N pool. The population of predators/omnivores indicated that treatment with SRU2 could provide enough soil NH4+-N to promote maize growth and increased the food resource for the soil fauna compared with the other treatments.

  9. 北京地区潮土对土霉素的吸附特性研究%Adsorption Analysis of Oxytetracycline on Fluvo-aquic Soils in Beijing

    Institute of Scientific and Technical Information of China (English)

    李国傲; 陈振贺; 刘志富; 李烨

    2015-01-01

    Nearly 25%of the total area in Beijing is fluvo-aquic soils,whose adsorption characteristics of tetra-cycline antibiotics have not been investigated.This research,with the help of OECD Guideline 106,investiga-ted the absorption characteristics of oxytetracycline in the fluvo-aquic soils in Beijing.Our research found that the adsorption kinetics of oxytetracycline in the fluvo-aquic soils is correspond to Elovich equation.The initial concentration of oxytetracycline will affect the adsorption rate.Absorption rate reaches the maximum when the concentration is 2 mg/L and the minimum when 10 mg/L.For absorption percentage,as initial concentration increases,the adsorption percentage first increases and then decreases.The relationship between temperature and average absorption rate is negatively correlated.In our experimental context,the adsorption isotherm is con-sistent with both linear adsorption isotherm equation and Freundlich isotherm equation.The adsorption is a spontaneous endothermic reaction.Fluvo-aquic soils adsorption capacity of oxytetracycline has a positive relation with the content of silt and clay.Adsorption of oxytetracycline on fluvo-aquic soils was affected by initial con-centration,temperature,and soil properties.It is helpful to control pollution of oxytetracycline and protect soils if the mechanisms are understood deeply.%北京近1/4区域土壤属于潮土,潮土对四环素类抗生素的吸附特性还鲜有报道。采用OECD Guideline 106的方法,研究土霉素在北京地区潮土上的吸附特性。结果表明,土霉素在潮土中的吸附动力学过程符合Elovich方程,土霉素初始浓度会影响吸附速率,2 mg/L时最大,10 mg/L时最小。吸附百分比随着初始浓度的升高,先增大后减小。温度和平均吸附速率呈负相关。实验浓度下,吸附等温线符合线性等温方程和Freundlich方程,吸附是自发的吸热反应。潮土对土霉素的吸附量和粉粒及黏粒含

  10. Sustainable urban regime adjustments

    DEFF Research Database (Denmark)

    Quitzau, Maj-Britt; Jensen, Jens Stissing; Elle, Morten;

    2013-01-01

    The endogenous agency that urban governments increasingly portray by making conscious and planned efforts to adjust the regimes they operate within is currently not well captured in transition studies. There is a need to acknowledge the ambiguity of regime enactment at the urban scale. This directs......, inspired by Actor-Network Theory to demonstrate that regime incumbent actors can induce gradual regime adjustments at the urban scale. This is done through a case study of an urban development project, where the Municipality of Egedal in Denmark has successfully promoted energy efficient buildings through...

  11. Sodicity Properties of Saline Fluvo-aquic Soils around Wuliangsuhai Lake%乌梁素海周围盐化潮土钠质化特征

    Institute of Scientific and Technical Information of China (English)

    刘骏; 于会彬; 谢森; 席北斗; 蒋进元

    2011-01-01

    Sixteen composite soil samples from different depths (0-20 cm, >20-40 cm, >40-60 cm and >60-80 cm) were collected from four different halophyte communities, namely, Comm. Salicornia europaea (CSE), Comm. Suaeda glauca (CSG),Comm. Kalidium foliatum (CKF) and Comm. Sophora alopecuroides (CSA) located around Wuliangsuhai Lake. Based on measuring exchangeable sodium ion percentage (ESP), sodium absorption rate (SAR), pH, moisture and salinity, the salinization properties of saline fluvo-aquic soils were analyzed. The results showed that the means of salinity, ESP and SAR in CSE profile were highest, followed by CSG, CKF and CSA. The total contents of metal ions were highest in CSE profile, followed by CSG,CKF and CSA. The major cations were Ca2+ and Na+, while the major anions were C1 - and SO42- , though the contents of CO32 and HCO3 - were less. Chloride and sulphate were the main soil salinity, and carbonate existed as calcium carbonate. ESP was significantly and positively correlated with salinity ( R2 = 0. 834, P = 0. 0008 ) and SAR ( R2 = 0. 862, P = 0. 0002 ), indicating that ESP increases with the rise of salinity and SAR, and SAR can be used as a surrogate for ESP. The distribution of salts in soil profiles is formed from the combined effect of precipitation, evaporation, irrigation, groundwater, etc.%以乌梁素海周围盐角草(CSE)、碱蓬(CSG)、盐爪爪(CKF)和苦豆子(CSA)群落的盐化潮土为研究对象,分别采集0~20,>20~40,>40~60和>60~80 cm共16个混合土样.测定土壤pH,含水量,含盐量,钠吸附比(SAR)和交换性钠离子百分率(ESP)等指标,分析了土壤的碱化特征.结果表明:CSE土壤剖面含盐量,SAR和ESP的平均值最高,其次为CSG,CKF和CSA土壤.CSE土壤金属离子总量最大,其次为CSG,CKF和CSA;阳离子以Ca2+和Na+为主,阴离子以Cl-和SO2-4为主,而CO32-和HCO3-含量极低.土壤盐分主要以氯化物和硫酸盐为主,碳酸盐以碳酸钙形式存在.ESP与含盐量(R2

  12. Measuring autocratic regime stability

    Directory of Open Access Journals (Sweden)

    Joseph Wright

    2016-01-01

    Full Text Available Researchers measure regime stability in autocratic contexts using a variety of data sources that capture distinct concepts. Often this research uses concepts developed for the study of democratic politics, such as leadership change or institutionalized authority, to construct measures of regime breakdown in non-democratic contexts. This article assesses whether the measure a researcher chooses influences the results they obtain by examining data on executive leadership, political authority, and autocratic regimes. We illustrate the conceptual differences between these variables by extending recent studies in the literature on the political consequences of non-tax revenue and unearned foreign income.

  13. THE INFLUENCED FLOW REGIMES

    Directory of Open Access Journals (Sweden)

    Gavril PANDI

    2011-03-01

    Full Text Available The influenced flow regimes. The presence and activities ofhumanity influences the uniform environmental system, and in this context, therivers water resources. In concordance with this, the natural runoff regime suffersbigger and deeper changes. The nature of these changes depending on the type anddegree of water uses. The multitude of the use cause different types of influence,whit different quantitative aspects. In the same time, the influences havequalitative connotations, too, regarding to the modifications of the yearly watervolume runoff. So the natural runoff regime is modified. After analyzing thedistribution laws of the monthly runoff, there have been differenced four types ofinfluenced runoff regimes. In the excess type the influenced runoff is bigger thanthe natural, continuously in the whole year. The deficient type is characterized byinverse rapports like the first type, in the whole year. In the sinusoidal type, theinfluenced runoff is smaller than the natural in the period when the water isretained in the lake reservoirs, and in the depletion period the situation inverts. Atthe irregular type the ratio between influenced and natural runoff is changeable ina random meaner monthly. The recognition of the influenced regime and the gradeof influence are necessary in the evaluation and analysis of the usable hydrologicalriver resources, in the flood defence activities, in the complex scheme of thehydrographic basins, in the environment design and so on.

  14. World Nonproliferation Regime

    Institute of Scientific and Technical Information of China (English)

    Ouyang Liping; Wu Xingzuo

    2007-01-01

    2006 witnessed an intense struggle between nuclear proliferation and nonproliferation. Iran's nuclear issue and North Korea's nuclear test have cast a deep shadow over the current international nonproliferation regime. The international contest for civil nuclear development became especially fierce as global energy prices went up. Such a situation , to some extent, accelerated the pace of nuclear proliferation. Furthermore, the existing international nonproliferation regime, based upon the Nuclear Nonproliferation Treaty (NPT), was affected by loopholes, and the U.S. failed in its ambition to unite other forces to mend fences. The international community needs to come up with a comprehensive and long-term strategy to meet the demand for an effective future nonproliferation regime in a healthy nuclear order.

  15. Supply regimes in fisheries

    DEFF Research Database (Denmark)

    Nielsen, Max

    2006-01-01

    -economic supply model with mesh sizes is developed. It is found that in the presence of realistic management schemes, the supply curves are close to vertical in the relevant range. Also, the supply curve under open access with mesh size limitations is almost vertical in the relevant range, owing to constant......Supply in fisheries is traditionally known for its backward bending nature, owing to externalities in production. Such a supply regime, however, exist only for pure open access fisheries. Since most fisheries worldwide are neither pure open access, nor optimally managed, rather between the extremes......, the traditional understanding of supply regimes in fisheries needs modification. This paper identifies through a case study of the East Baltic cod fishery supply regimes in fisheries, taking alternative fisheries management schemes and mesh size limitations into account. An age-structured Beverton-Holt based bio...

  16. PRELIMINARY STUDY ON ACIDITY AND ACIDIFICATION SENSITIVITY OF FLUVO-AQUIC SOILS OF NORTH CHINA PLAIN%华北平原潮土酸度特征与酸化敏感性的初步探讨

    Institute of Scientific and Technical Information of China (English)

    张瑜; 郭景恒

    2011-01-01

    Fluvo-aquic soils in North China Plain were collected for the preliminary investigation of their acidity characteristics and acidification sensitivity,under intensive agricultural utilization.Soil pH significantly correlated with nitrate,which indicated that overuse of nitrogen fertilizer was the important driving factor for soil pH decline.Dissolution of CaCO3 is the main acidification buffer process in these fluvo-aquic soils.Soils with lower CaCO3 were sensitive to the acid input with fast pH drop,while soils with higher CaCO3 were insensitive to continuous acid input.Critical acid buffer capacity,acid buffer intensity and pH buffer intensity,calculated based on acid-base titration curve,positively correlated with CaCO3 content.Such relationships clearly showed the strong dependence of acidification sensitivity on soil carbonates.Depletion of soil carbonates induced by intensive utilizations will result in,in turn,faster decrease in soil pH,which brings potential risk to soil quality and environment health.Methodology improvement on acidification sensitivity assessment,with enough consideration to the buffering characteristics,is the most urgent task in the regulation of acidification in fluvo-aquic soils.%采集华北平原潮土样品对其酸度特征和酸化敏感性进行了初步探讨.结果显示,过量施用氮肥导致的硝酸盐积累是华北平原潮土pH值下降的重要原因,硝酸根与土壤pH值呈显著负相关.碳酸钙溶解是当前潮土缓冲酸化的主要过程,决定着潮土对外界酸输入的响应方式和敏感程度.随着酸输入量的增加,低碳酸钙土壤的pH值迅速下降,但高碳酸钙的石灰性潮土对酸输入不敏感.潮土酸化的敏感性主要决定于碳酸钙含量,临界缓冲容量、酸缓冲强度及pH缓冲强度等土壤敏感性指标均与碳酸钙含量呈显著正相关.初步分析显示,在长期集约化耕作的影响下低碳酸钙潮土存

  17. Dimagrire in regime mediatico

    OpenAIRE

    Boutaud, Jean-Jacques

    2012-01-01

    publication en italien : BOUTAUD Jean-Jacques, « Dimagrire in regime mediatico », Dietetica e semiotica. Regimi di Senso, a cura di Dario Mangano e Gianfranco Marrone, Mimesis Edizioni, Milano, 2013, p. 19-38 Il titolo può leggersi in molti modi. Per esempio: dietetica e semiotica sono due regimi di senso, uno alimentare e l'altro comunicativo, con pari dignità, dunque da paragonare fra loro. Oppure: grazie alla semiotica la dietetica appare, non più come un regime alimentare, ma come un r...

  18. The efficiency of applying phosphate on rice and utilization rate in calcareous fluvo-aquic soil%石灰性灰潮土水稻施磷效应及利用率

    Institute of Scientific and Technical Information of China (English)

    姜剑平; 刘伯芹

    2012-01-01

    The effects of different phosphorus fertilization level on soil rapid available phosphorus and rice yield are studied in calcareous fluvo-aquic soil of Tongzhou area, the utilization rate of phosphate fertilizer is determined in different phosphorus fertilization level. The results show: the phosphate fertilizer coefficient of calcareous fluvo-aquic soil is 1.72 in middle containing phosphorus soil, the critical value is 6.0 mg/kg; the reasonable applying phosphate fertilizer can significantly increase the yield of rice, and the yield is increased with the increasing of applying phosphate amount below a certain phosphorus fertilization level, the best phosphorus fertilization amount is 3.8 kg, and the phosphorus fertilization amount of the highest yield is 9.4 kg. The phosphate utilization rate is decreased with the increasing of applying phosphate amount, the averaKe utilization rate is 8.5%.%以通州区石灰性灰潮土为供试土壤,研究了不同施磷水平对土壤速效磷含量及水稻产量的影响,测定了水稻不同施磷水平下磷肥的利用率。结果表明,在中等含磷的土壤上,石灰性灰潮土的磷肥系数为1.72,磷肥临界值为6.0mg/kg;水稻合理施用磷肥能显著增产,但产量只在一定的施磷水平下随着施磷量的增加而增加,其667m。最经济施磷量为3.8kg,最高产量施磷量为9.4kg。磷肥利用率则随施磷量的增加而逐渐下降,平均利用率为8.5%。

  19. Effects of Intercropping Mushroom on the Fertility and Biological Activity in a Fluvo-aquic Soil for Planting Tomato%番茄地套作蘑菇对土壤肥力和生物活性的影响

    Institute of Scientific and Technical Information of China (English)

    王军涛; 尹睿; 林先贵; 胡君利; 李晶; 王一明; 陈瑞蕊

    2012-01-01

    通过温室盆栽试验,研究了套作双孢蘑菇(Agaricus bisporus)对潮土速效养分含量、微生物数量、关键酶活性以及番茄(Lycopersicon esculentum Mill.)生长的影响。结果发现,与对照相比,添加双孢蘑菇培养基质对土壤有机碳、矿质氮与速效磷含量均没有显著影响,但速效钾含量显著增加(P〈0.05),且土壤细菌数量趋于增加、真菌数量显著减少(P〈0.05),土壤脲酶与磷酸酶活性显著增强(P〈0.05)、纤维素酶活性显著下降(P〈0.05),番茄植株地上部和地下部生物量分别增加130%和67%,但产量没有明显变化;在添加培养基质基础上再接种双孢蘑菇菌种与不接种相比显著降低土壤有机碳含量和脲酶活性(P〈0.05),番茄植株生物量也降到与对照相接近的水平,尽管番茄产量没有明显变化,但额外收获了双孢蘑菇。结果表明,套作双孢蘑菇对潮土生物活性具有促进作用,并可以增加单位面积经济产出,因而在潮土地区具有推广潜力。%A pot experiment in greenhouse was carried out to investigate the effects of intercropping mushroom(Agaricus bisporus) on soil available nutrient contents,microbial population sizes,enzyme activities and tomato(Lycopersicon esculentum Mill.) growth in a fluvo-aquic soil.The amendment of substrate of mushroom had no significant effects on soil organic carbon,mineral nitrogen and available phosphorus,as well as fruit yield of tomato,while had a positive effect on soil available potassium content,bacterial population size,urease and phosphate activities,as well as vegetative biomass of tomato plants,and had negative effects on soil fungal population size and cellulose activity.However,the inoculation of mushroom strain Zhejiang 20 significantly decreased(P 0.05) soil organic carbon,urease activities,and vegetative biomass of tomato plants compared with the treatment without inoculation.In the intercropping

  20. 不同质地潮土夏玉米推荐施肥方法研究%Studies on recommended fertilization methods of summer maize in different fluvo-aquic soil texture

    Institute of Scientific and Technical Information of China (English)

    王宜伦; 李慧; 张晓佳; 韩燕来; 谭金芳

    2012-01-01

    Maize is the most cultivated grain crop in China. Realizing high yields of summer maize is important in ensuring food security in the country. There are, however, several known problems with summer maize production (e.g., excessive dosage and unreasonable periods of nitrogen application) that hinder high-yield realization. To increase fertilizer use efficiency and grain yield of summer maize, field experiments were conducted to determine the differences in summer maize yield, economic benefits, N, P and K. Use efficiency between Nutrient Expert (NE) and Agro-Services International Inc (ASI) recommended fertilizations in sand-loam, medium-loam and sticky-loam fluvo-aquic soils in Henan Province. The results showed that NE recommended fertilization treatment significantly increased maize yields in the three different soil textures. Summer maize yield, economic benefits and protein contents were ail significantly different (F medium-loam > sandy-loam soils. The output/input ratio of NE recommended fertilization treatment was higher than that of ASI recommended fertilization. Recommended fertilization treatments significant increased plant nutrient accumulation, which benefited grain protein and yield. Compared with farmer conventional fertilization (CK), maize yield increased by 7.22%, 3.84% and 11.32% for NE recommended fertilization treatment and by 13.44%, 10.60% and 11.20% for ASI recommended fertilization treatment in sandy-loam, medium-loam and clay-loam soils, respectively. N fertilizer increased yield the most under NE recommended fertilization treatment. N agronomic efficiency, use efficiencies of N, P and K fertilizers were in the order of clay-loam > medium-loam > sandy-loam. However, P and K fertilizers agronomic efficiencies were in the order of sandy-loam > clay-loam > medium-loam. Fertilizer agronomic efficiency was in the order of P fertilizer > K fertilizer > N fertilizer in all the three soil textures. NE recommended fertilization was most suitable

  1. Political Regimes and Economic Growth

    Directory of Open Access Journals (Sweden)

    Carlos Pinho

    2009-12-01

    Full Text Available Are political regimes drivers of economic growth? While political institutions are influenced by economic development, they are in turn a key determinant of the development process. This study builds in the Neoclassical Growth theory to identify the influence of political regimes on economic development through a panel data sample of 170 countries from 1960 to 2000. Results suggest that once fixed effects are considered, the positive relationship between income per capita and political regimes measured by different democracy variables disappears.

  2. Unitary Housing Regimes in Transition

    DEFF Research Database (Denmark)

    Bengtsson, Bo; Jensen, Lotte

    2013-01-01

    to the Danish and Swedish housing regimes are analysed and the responses and outcomes in terms of policy change and/or institutional continuity (path dependence) are compared. Overall, the more decentralized Danish housing regime seems to have resisted pressures for change and retrenchment better so far than...

  3. 'Regime shopping' across (blurring) boundaries

    NARCIS (Netherlands)

    Houwerzijl, M.S.; Evju, Stein

    2014-01-01

    This book chapter identifies and explores the (blurring) boundaries between the legal regimes for labour mobility across the EU. In the context of - what is sometimes called - 'regime shopping' a close look is taken into the law on freedom of movement within the EU. Several categories of transnation

  4. Regime shifts in resource management

    NARCIS (Netherlands)

    de Zeeuw, A.J.

    2014-01-01

    Resource management has to take account of the possibility of tipping points and regime shifts in ecological systems that provide the resources. This article focuses on the typical model of regime shifts in the ecological literature and analyzes optimal management and common-property issues when tra

  5. The Choice of Monetary Regime

    DEFF Research Database (Denmark)

    Østrup, Finn

    , a comparisonbetween monetary regimes suggests that welfare is highest under nominalincome targeting where the nominal income target is determined to bring aboutprice stability.Keywords: Monetary regimes; fiscal policy; monetary non-neutrality.JEL classicification: E42, E61, E62.......The article examines how government spending is determined in a closedeconomy where the nominal wage is pre-set through contracts and the wage settershave perfect foresight regarding subsequent policy decisions. The monetaryregime affects government spending because: (i) with a pre-set nominal wage......, agiven change in government spending has different effects on employment andinflation under different monetary regimes, and (ii) the authorities' inclinationto expand government spending is affected by the inflation rate which dependson the monetary regime. If the costs related to inflation are high...

  6. MULTILATERAL DIPLOMACY AND INTERNATIONAL REGIMES

    Directory of Open Access Journals (Sweden)

    BENEA Ciprian-Beniamin

    2014-12-01

    Full Text Available The history of diplomacy can by divided in three main periods: one is that of occasional diplomacy peculiar to Middle Ages, while other belong to permane diplomacy, peculiar to modern times. But this one can be divided in two parts, too: one with a bilateral character, previos to 1st World War, and one with a multilateral character, manifested especially after the end on 1st World War. This third type is the focus of present paper. And it cannot be separated from the newly international constructs: international regimes, and international organizations. International instritutions the area where international regimes are belonging to – are legal constructs which provide the formal (and legal framework for continous negotiations. They are the most visible part of the new diplomacy – the one which has a permanent character, and it has an more open face. Anyway, the most important connection has to do with the international institutions, international regimes, and multilateral international negotiations. In the era of the new diplomacy, they all have a permanent character. International institutions help international negotiations carring on; while in their turn, they provide the base for international regimes’ creation, and especially for their evolution. The international regimes’ evolution is an inseparable part of a permanent international framework. And if there is missing a permanent international framework (international organization connected to a specific regime, this regime is a difuse one, its members have only informal relations among them, while they survey each other, looking at their behavior, but they don’t have a formal relationship among them, which could help them solving their future common interests, and protect them from their common fears. International regimes are very important in the era when evrithing touches, and influences everything. In the same time, the complexity of our present world can be successfully

  7. Great Lakes' regional climate regimes

    Science.gov (United States)

    Kravtsov, Sergey; Sugiyama, Noriyuki; Roebber, Paul

    2016-04-01

    We simulate the seasonal cycle of the Great Lakes' water temperature and lake ice using an idealized coupled lake-atmosphere-ice model. Under identical seasonally varying boundary conditions, this model exhibits more than one seasonally varying equilibrium solutions, which we associate with distinct regional climate regimes. Colder/warmer regimes are characterized by abundant/scarce amounts of wintertime ice and cooler/warmer summer temperatures, respectively. These regimes are also evident in the observations of the Great Lakes' climate variability over recent few decades, and are found to be most pronounced for Lake Superior, the deepest of the Great Lakes, consistent with model predictions. Multiple climate regimes of the Great Lakes also play a crucial role in the accelerated warming of the lakes relative to the surrounding land regions in response to larger-scale global warming. We discuss the physical origin and characteristics of multiple climate regimes over the lakes, as well as their implications for a longer-term regional climate variability.

  8. Cloud regimes as phase transitions

    Science.gov (United States)

    Stechmann, Samuel N.; Hottovy, Scott

    2016-06-01

    Clouds are repeatedly identified as a leading source of uncertainty in future climate predictions. Of particular importance are stratocumulus clouds, which can appear as either (i) closed cells that reflect solar radiation back to space or (ii) open cells that allow solar radiation to reach the Earth's surface. Here we show that these clouds regimes -- open versus closed cells -- fit the paradigm of a phase transition. In addition, this paradigm characterizes pockets of open cells as the interface between the open- and closed-cell regimes, and it identifies shallow cumulus clouds as a regime of higher variability. This behavior can be understood using an idealized model for the dynamics of atmospheric water as a stochastic diffusion process. With this new conceptual viewpoint, ideas from statistical mechanics could potentially be used for understanding uncertainties related to clouds in the climate system and climate predictions.

  9. Friction Regimes in the Lubricants Solid-State Regime

    NARCIS (Netherlands)

    Schipper, D.J.; Maathuis, O.; Dowson, D.; Taylor, C.M.; Childs, T.H.C.; Dalmaz, G.

    1995-01-01

    Friction measurements were performed in the lubricant's solid-state regime to study the transition from full-film lubrication, in which the separation is maintained by a solidified lubricant, to mixed lubrication. Special attention is paid to the influence of temperature (inlet viscosity) and roughn

  10. On the regimes of premixing

    Energy Technology Data Exchange (ETDEWEB)

    Angelini, S.; Theofanous, T.G.; Yuen, W.W. [California Univ., Santa Barbara, CA (United States). Center for Risk Studies and Safety

    1998-01-01

    The conditions of the MAGICO-2000 experiment are extended to more broadly investigate the regimes of premixing, and the corresponding internal structures of mixing zones. With the help of the data and numerical simulations using the computer code PM-ALPHA, we can distinguish extremes of behavior dominated by inertia and thermal effects - we name these the inertia and thermal regimes, respectively. This is an important distinction that should guide future experiments aimed at code verification in this area. Interesting intermediate behaviors are also delineated and discussed. (author)

  11. Monetary regimes in open economies

    NARCIS (Netherlands)

    Korpos, A.

    2006-01-01

    This thesis presents a two-country open economy framework for the analysis of strategic interactions among monetary authorities and wage bargaining institutions. From this perspective, the thesis investigates the economic consequences of replacing flexible and fixed exchange rate regimes with a mone

  12. Friction Regimes in the Lubricants Solid-State Regime

    OpenAIRE

    Schipper, D.J.; Maathuis, O.; Dowson, D; Taylor, C.M.; Childs, T.H.C.; Dalmaz, G.

    1995-01-01

    Friction measurements were performed in the lubricant's solid-state regime to study the transition from full-film lubrication, in which the separation is maintained by a solidified lubricant, to mixed lubrication. Special attention is paid to the influence of temperature (inlet viscosity) and roughness on this transition. The friction measurements showed that in the lubricants solid-state region three lubrication modes can be distinguished: A) full-film lubrication; separation is maintained b...

  13. The Concept of Truth Regime

    Directory of Open Access Journals (Sweden)

    Lorna Weir

    2008-07-01

    Full Text Available “Truth regime” is a much used but little theorized concept, with the Foucauldian literature presupposing that truth in modernity is uniformly scientific/quasi-scientific and enhances power. I argue that the forms of truth characteristic of our present are wider than Foucault recognized, their relations to power more various, and their historicity more complex. The truth regime of advanced modernity is characterized by multiple, irreducible truth formulae that co-exist and sometimes vie for dominance. A truth formula stabilizes a network of elements: a relation between representation and presentation (words and things, truth and non-truth, and the place of the subject in discourse. Our contemporary truth regime comprises radically heterogeneous truthful knowledges – science, governance, religion/politics, and common culture – that have distinct histories and relations to power.

  14. Demystifying optimal dynamic treatment regimes.

    Science.gov (United States)

    Moodie, Erica E M; Richardson, Thomas S; Stephens, David A

    2007-06-01

    A dynamic regime is a function that takes treatment and covariate history and baseline covariates as inputs and returns a decision to be made. Murphy (2003, Journal of the Royal Statistical Society, Series B 65, 331-366) and Robins (2004, Proceedings of the Second Seattle Symposium on Biostatistics, 189-326) have proposed models and developed semiparametric methods for making inference about the optimal regime in a multi-interval trial that provide clear advantages over traditional parametric approaches. We show that Murphy's model is a special case of Robins's and that the methods are closely related but not equivalent. Interesting features of the methods are highlighted using the Multicenter AIDS Cohort Study and through simulation. PMID:17688497

  15. The EU Commission consultation regime

    OpenAIRE

    Quittkat, Christine; Finke, Barbara

    2008-01-01

    "The present consultation regime of the European Commission is marked by the role the Commission assigns to non-governmental actors or civil society organisations (CSOs). The Commission's documents on its policy of consultation and cooperation with external non-governmental actors reveal that a reflective approach has emerged during the 1980s, referring to a more elaborate concept of 'good governance'. The gradual extension is most noticeable in the change of terminology, from ‘consultation’ ...

  16. The International Climate Change Regime

    Science.gov (United States)

    Yamin, Farhana; Depledge, Joanna

    2005-01-01

    Aimed at the increasing number of policy-makers, stakeholders, researchers, and other professionals working on climate change, this volume presents a detailed description and analysis of the international regime established in 1992 to combat the threat of global climate change. It provides a comprehensive accessible guide to a high-profile area of international law and politics, covering not only the obligations and rights of countries, but ongoing climate negotiations as well.

  17. Disclosure regimes and corporate governance

    OpenAIRE

    Wüstemann, Jens

    2004-01-01

    As there is a strong relationship of disclosure regimes and corporate governance the internationally varying distribution of information rights can be interpreted as a function of different systems of corporate governance. A disclosure system comprises all legally recognized information claims that a system of corporate governance or a financial system furnishes financial contracting parties with: Both public disclosure and disclosure via private information channels may serve value-relevant ...

  18. Exchange Rate Regimes and Location

    OpenAIRE

    Ricci, Luca Antonio

    1997-01-01

    This paper investigates the effects of fixed versus flexible exchange rate regimes on location choices of firms and on the degree of specialization of countries. In a two-country two-differentiated-good monetary model, demand, supply, and monetary shocks arise after wages are set and prices are optimally chosen. The exchange rate performs then an adjustment role for firms located in the country relatively specialized in the good they produce, but it constitutes a factor of disturbance for the...

  19. Exchange rate regimes and monetary arrangements

    Directory of Open Access Journals (Sweden)

    Ivan Ribnikar

    2005-06-01

    Full Text Available There is a close relationship between a country’s exchange rate regime and monetary arrangement and if we are to examine monetary arrangements then exchange rate regimes must first be analysed. Within the conventional and most widely used classification of exchange rate regimes into rigid and flexible or into polar regimes (hard peg and float on one side, and intermediate regimes on the other there, is a much greater variety among intermediate regimes. A more precise and, as will be seen, more useful classification of exchange rate regimes is the first topic of the paper. The second topic is how exchange rate regimes influence or determine monetary arrangements and monetary policy or monetary policy regimes: monetary autonomy versus monetary nonautonomy and discretion in monetary policy versus commitment in monetary policy. Both topics are important for countries on their path to the EU and the euro area

  20. Merging of Rhine flow regimes

    Science.gov (United States)

    Boessenkool, Berry; Bronstert, Axel; Bürger, Gerd

    2016-04-01

    The Rhine flow regime is changing: (a) in the alpine nival regime, snow melt floods occur earlier in the year and (b) in the pluvial middle-Rhine regime, rainfall induced flood magnitudes rise. The seasonality of each is currently separated in time, but it is conceivable that this may shift due to climate change. If extremes of both flood types coincide, this would create a new type of hydrologic extreme with disastrous consequences. Quantifying the probability for a future overlap of pluvial and nival floods is therefore of high relevance to society and particularly to reinsurance companies. In order to investigate possible changes in magnitude and timing of flood types, we are developing a chain of physical models for spatio-temporal combination of flood probabilities. As input, we aim to use stochastically downscaled temperature and rainfall extremes from climate model weather projections. Preliminary research shows a six-week forward-shift of peak discharge at the nival gauge Maxau in the past century. The aim of presenting our early-stage work as a poster is to induce an exchange of ideas with fellow scientists in close research disciplines.

  1. The effect of conservation tillage on the structural characteristics of Fluvo-aquic soil%保护性耕作对潮土结构特性的影响

    Institute of Scientific and Technical Information of China (English)

    赵红; 吕贻忠

    2009-01-01

    研究不同保护性耕作措施对潮土结构特性的影响,探求不同秸秆还田方式下土壤结构的变化规律.以河北省石家庄市栾城县长期定位试验为研究基础,采用了传统翻耕、翻耕秸秆还田、旋耕秸秆还田、免耕覆盖还田、免耕立秆还田和免耕粉碎还田6种处理,分别对不同耕层的土壤容重、有机碳含量、团聚体及有机无机复合体进行了测定,对比分析了不同保护性耕作对潮土结构特性的影响.结果表明:免耕覆盖还田的土壤容重值最低;干筛情况下,免耕秸秆覆盖还田的MWD值显著高于其它处理30.4%~47.4%,而湿筛情况下,免耕立秆还田与粉碎还田MWD值高于其它处理;立秆还田的土壤分散系数最低,而粉碎还田的分散系数比其它处理高20.48%~330.93%;翻耕处理的原土复合量、原土复合度分别高于免耕处理10.82%~21.62%、8.97%~20.97%.不同秸秆还田方式对土壤结构稳定性的影响有很大差异:覆盖还田能改善田间土壤结构;立秆还田能提高微团聚体的稳定性;粉碎还田通过增加土壤有机碳含量而增加水稳性大团聚体的含量.%The effect of different conservation tillage measurement on structural characteristics of Fluvo-aquic soil were studied, and the variation law of soil structure under different ways of straw returning were searched. This study is based on long field experi-ments of Luancheng country of Hebei province Shijiazhuang city, six treatments of tillage systems were utilized: conventional tillage、tillage with straw returning、rotary tillage with straw returning, no tillage with mulch, no tillage with standing stubble and no tillage with crush returning, soil bulk density, soil organic carbon content, aggregate and organo-mineral complexes were measured. The results showed: the lowest soil bulk density value is no tillage with mulch; the MWD value of no tillage with mulch significantly higher than other treatments 30

  2. Alberta oil sands royalty regime

    International Nuclear Information System (INIS)

    The long term objective of the Oil Sands Business Unit of Alberta Energy is to pave the way for Alberta's bitumen production to reach 3 million barrels per day by 2020. This presentation described the national government's role in resource development. It was emphasized that since the Crown is the owner of the oil sands resource, it would benefit by providing strategic leadership and by generating a larger royalty base. The oil sands fiscal regime was described with reference to generic royalty, risk sharing, investment, and project economics. Business rule principles were also outlined along with criteria for project expansions. Both upstream and downstream challenges and opportunities were listed. 4 figs

  3. Accommodating human values in the climate regime

    NARCIS (Netherlands)

    Cook, Rosalind; Tauschinsky, Eljalill

    2008-01-01

    The climate regime addresses one of the most important challenges facing humankind today. However, while the environmental and economic sides of the problem are well represented, it lacks the inclusion of social and human aspects. The human rights regime, in contrast, is a regime which has been esta

  4. Analysis on basic soil productivity change of winter wheat in fluvo-aquic soil under long-term fertilization%长期不同施肥措施下潮土冬小麦农田基础地力演变分析

    Institute of Scientific and Technical Information of China (English)

    贡付飞; 蔡典雄; 查燕; 武雪萍; 黄绍敏; 徐明岗; 张会民; 刘海龙; 姜志伟; 王小彬

    2013-01-01

      Fluvo-aquic soil areas are important grain production areas in China. With the population increasing and the economy developing, China is facing the big challenge to increase grain yield and ensure food security. Because the use of fertilizer has reached a high level, increasing fertilizer application is no longer an effective way to increase production. The results of many long-term soil fertility experiments show that the basic soil productivity (BSP) change was important to reduce fertilizer application rates and increase crop yield. Thus, studying the change characteristics of BSP in fluvo-aquic soil areas has theoretical and practical significance to guide the proper oriented soil fertility cultivation to meet the national demand for the grain increase.   This paper analyzed the trends and influencing factors of BSP in winter wheat seasons under different long-term fertilization processes based on National Soil Fertility and Fertilizer Effects Long-term Monitoring Experiments, in order to provide a scientific basis to strengthen the oriented soil fertility cultivation in fluvo-aquic soil areas of China. The research was based on an 18-year field experiment on fluvo-aquic soil in Zhengzhou City, Henan Province. Five fertilization treatments were set up in the experiment, including CK (no fertilizer), NPK (single inorganic fertilizer), NPKM (organic fertilizer and inorganic fertilizer), 1.5 NPKM (organic fertilizer and inorganic fertilizer, the count was 1.5 times of NPKM), and NPKS (straw and inorganic fertilizer). The yields based on BSP were simulated by using the DSSAT (decision support system for agro-technology transfer) model. First, we input the parameters of soil, weather and field management into the DSSAT model, then modified and calibrated the crop variety parameters based on the measured yield;after that, we set up the fertilization opinion in the model to get the BSP yield. The contribution percentage of BSP to yield was calculated by the

  5. Adaptation in Collaborative Governance Regimes

    Science.gov (United States)

    Emerson, Kirk; Gerlak, Andrea K.

    2014-10-01

    Adaptation and the adaptive capacity of human and environmental systems have been of central concern to natural and social science scholars, many of whom characterize and promote the need for collaborative cross-boundary systems that are seen as flexible and adaptive by definition. Researchers who study collaborative governance systems in the public administration, planning and policy literature have paid less attention to adaptive capacity specifically and institutional adaptation in general. This paper bridges the two literatures and finds four common dimensions of capacity, including structural arrangements, leadership, knowledge and learning, and resources. In this paper, we focus on institutional adaptation in the context of collaborative governance regimes and try to clarify and distinguish collaborative capacity from adaptive capacity and their contributions to adaptive action. We posit further that collaborative capacities generate associated adaptive capacities thereby enabling institutional adaptation within collaborative governance regimes. We develop these distinctions and linkages between collaborative and adaptive capacities with the help of an illustrative case study in watershed management within the National Estuary Program.

  6. Measuring the effectiveness of international environmental regimes

    Energy Technology Data Exchange (ETDEWEB)

    Helm, C.; Sprinz, D.F.

    1999-05-01

    While past research has emphasized the importance of international regimes for international governance, systematic assessments of regime effects are missing. This article derives a standardized measurement concept for the effectiveness of international environmental regimes by developing an operational rational choice calculus to evaluate actual policy simultaneously against a non-regime counterfactual and a collective optimum. Subsequently, the empirical feasibility of the measurement instrument is demonstrated by way of two international treaties regulating transboundary air pollution in Europe. The results demonstrate that the regimes indeed show positive effects - but fall substantially short of the collective optima. (orig.)

  7. Regime Jumps in Electricity Prices

    International Nuclear Information System (INIS)

    Electricity prices are known to be very volatile and subject to frequent jumps due to system breakdown, demand shocks, and inelastic supply. As many international electricity markets are in some state of deregulation, more and more participants in these markets are exposed to these stylised facts. Appropriate pricing, portfolio, and risk management models should incorporate these facts. Authors have introduced stochastic jump processes to deal with the jumps, but we argue and show that this specification might lead to problems with identifying the true mean-reversion within the process. Instead, we propose using a regime jump model that disentangles mean-reversion from jump behaviour. This model resembles more closely the true price path of electricity prices

  8. Propagation Regime of Iron Dust Flames

    Science.gov (United States)

    Tang, Francois-David; Goroshin, Samuel; Higgins, Andrew J.

    2012-01-01

    A flame propagating through an iron-dust mixture can propagate in two asymptotic regimes. When the characteristic time of heat transfer between particles is much smaller than the characteristic time of particle combustion, the flame propagates in the continuum regime where the heat released by reacting particles can be modelled as a space-averaged function. In contrast, when the characteristic time of heat transfer is much larger than the particle reaction time, the flame can no longer be treated as a continuum due to dominating effects associated with the discrete nature of the particle reaction. The discrete regime is characterized by weak dependence of the flame speed on the oxygen concentration compared to the continuum regime. The discrete regime is observed in flames propagating through an iron dust cloud within a gas mixture containing xenon, while the continuum regime is obtained when xenon is substituted with helium.

  9. Accommodating human values in the climate regime

    Directory of Open Access Journals (Sweden)

    Rosalind Cook

    2008-12-01

    Full Text Available The climate regime addresses one of the most important challenges facing humankind today. However, while the environmental and economic sides of the problem are well represented, it lacks the inclusion of social and human aspects. The human rights regime, in contrast, is a regime which has been established precisely to implement human values. This article ex-plains the problems of climate change in terms of human values and argues that some proce-dures from the human rights regime offer possibilities for improvement. It is submitted that through the inclusion of human rights instruments, such as individual communication, pro-gressive realisation and authoritative interpretation, the inclusion of human values into the climate regime will be facilitated. This article presents these instruments and discusses their potential for inclusion in the climate regime.

  10. Commodity Price Volatility Across Exchange Rate Regimes

    OpenAIRE

    John T. Cuddington; Hong Liang

    1998-01-01

    This paper documents a new "stylized fact" regarding commodity prices using alternative datasets covering the period from 1880 to 1996: The volatility of real commodity prices, defined as nominal commodity prices deflated by the manufacturing unit value index, is higher under flexible-exchange rate regimes than fixed-exchange rate regimes. Furthermore, changes in exchange regime are associated with changes in the persistence of commodity price shocks. Implications of this finding for open-eco...

  11. US Forest Service LANDFIRE Historical Fire Regimes

    Data.gov (United States)

    US Forest Service, Department of Agriculture — Historical fire regimes, intervals, and vegetation conditions are mapped using the Vegetation Dynamics Development Tool (VDDT). These data support fire and...

  12. Synergies between nonproliferation regimes: A pragmatic approach

    International Nuclear Information System (INIS)

    Full text: With the recent progress in establishing international nonproliferation regimes, the question of synergies between different verification and monitoring regimes is becoming more acute. Three multilateral and universal nonproliferation organisations covering safeguards on civil nuclear materials, nuclear testing, and chemical weapons are up and running. A regime on biological weapons is under negotiation. Several regional organisations concerned with monitoring nonproliferation commitments in the nuclear field are in place; others are being established. Past discussions on synergies between these regimes have suffered from being too far-reaching. These discussions often have not reflected adequately the political difficulties of cooperation between regimes with different membership, scope and institutional set-up. This paper takes a pragmatic look at exploiting synergies and identifies some potential and real overlaps in the work between different verification regimes. It argues for a bottom-up approach and identifies building blocks for collaboration between verification regimes. By realising such, more limited potential for cooperation, the ground could be prepared for exploiting other synergies between these regimes. (author)

  13. Capacitance densitometer for flow regime identification

    Science.gov (United States)

    Shipp, Jr., Roy L.

    1978-01-01

    This invention relates to a capacitance densitometer for determining the flow regime of a two-phase flow system. A two-element capacitance densitometer is used in conjunction with a conventional single-beam gamma densitometer to unambiguously identify the prevailing flow regime and the average density of a flowing fluid.

  14. LEGAL MATRIMONIAL REGIME IN B&H

    Directory of Open Access Journals (Sweden)

    Boris Krešić

    2011-12-01

    Full Text Available Matrimonial regime between spouses or between extramarital partners, and between parents and children is regulated by the Family Law Act of Bosnia and Herzegovina Federation, hereinafter FLA B&HF (SG FBiH 35/05, 41/05, Family Law Act of the Republic of Srpska, hereinafter FLA RS (SG RS”54/02, 41/08 and the Family Law Act of Brčko District, hereinafter FLA BD (SG RS, 66/07. Legal rules used for the regulation of the matrimonial regime between spouses, as well as between spouses and third parties make matrimonial regime (Ponjavić, 2005, p. 361. Matrimonial regime between spouses in family legislation in Bosnia and Herzegovina (B&H is regulated in two following ways: as legal matrimonial regime and as contract matrimonial regime. Legal regime is the one which applies on spouses if not arranged otherwise prior to contracting marriage or during marriage. In this paper the author indicates the differences between the legal matrimonial regimes of the two entities as well as those between the entities and Brčko District of Bosnia and Herzegovina.

  15. Explaining the Transition Between Exchange Rate Regimes

    OpenAIRE

    Masson, Paul; RUGE-MURCIA, Francisco J.

    2003-01-01

    This paper studies the transition between exchange rate regimes using a Markov chain model with time-varying transition probabilities. The probabilities are parameterized as nonlinear functions of variables suggested by the currency crisis and optimal currency area literature. Results using annual data indicate that inflation, and to a lesser extent, output growth and trade openness help explain the exchange rate regime transition dynamics.

  16. Multiscale regime shifts and planetary boundaries

    NARCIS (Netherlands)

    Hughes, T.P.; Carpenter, S.; Rockstrom, J.; Scheffer, M.; Walker, B.

    2013-01-01

    Life on Earth has repeatedly displayed abrupt and massive changes in the past, and there is no reason to expect that comparable planetary-scale regime shifts will not continue in the future. Different lines of evidence indicate that regime shifts occur when the climate or biosphere transgresses a ti

  17. LOW DOSE MAGNESIUM SULPHATE REGIME FOR ECLAMPSIA

    Directory of Open Access Journals (Sweden)

    Bangal V

    2009-09-01

    Full Text Available Pre- eclampsia is one of the commonest medical complications seen during pregnancy. It contributes significantly to maternal and perinatal morbidity and mortality. Dr.J.A.Pritchard in 1955, introduced magnesium sulphate for control of convulsions in eclampsia and is used worldwide. Considering the low body mass index of indian women, a low dose magnesium sulphate regime has been introduced by some authors. Present study was carried out at tertiary care centre in rural area. Fifty cases of eclampsia were randomly selected to find out the efficacy of low dose magnesium sulphate regime to control eclamptic convulsions. Maternal and perinatal outcome and magnesium toxicity were analyzed. It was observed that 86% cases responded to initial intravenous dose of 4 grams of 20% magnesium sulphate . Eight percent cases, who got recurrence of convulsion, were controlled by additional 2 grams of 20% magnesium sulphate. Six percent cases required shifting to standard Pritchard regime, as they did not respond to low dose magnesium sulphate regime. The average total dose of magnesium sulphate required for control of convulsions was 20 grams ie. 54.4% less than that of standard Pritchard regime. The maternal and perinatal morbidity and mortality in the present study werecomparable to those of standard Pritchard regime. The study did not find a single case of magnesium related toxicity with low dose magnesium sulphate regime. Low dose magnesium sulphate regime was found to be safe and effective in eclampsia.

  18. Framing of regimes and transition strategies

    DEFF Research Database (Denmark)

    Jensen, Jens Stissing

    2012-01-01

    This article suggests that transition strategies are always formulated in the context of specific representations of the regime and the challenges it faces. It is argued that the framing of a regime affects the envisioning of transition strategies. An analysis of the current development agenda...

  19. Food Regimes Revisited: A New Zealand Perspective

    Directory of Open Access Journals (Sweden)

    Michael Roche

    2012-01-01

    Full Text Available ‘Food Regimes’ was coined by Friedmann and McMichael in 1989 and provided a organising framework for a considerable amount of Australian and New Zealand research during a period of economic restructuring and ‘deregulation’. Subsequently Food regimes were overtaken by other perspectives in New Zealand and elsewhere including an interest in commodity productions chains, regulation, post-productivist landscapes, and post structural political economy. More recently McMichael has reintroduced Food Regimes to his analysis. The paper will compare and contrast McMichael’s earlier and more recent engagements with Food Regimes. The export meat, the dairy, and pip fruit industries of Zealand it will be used to illustrate points about the timing, boundaries and margins as well as the transformation of Food Regimes. Finally the paper will attempt to connect the more recent focus on commodity chain analysis and post productivist landscapes with McMichael’s renewed interest in food Regimes.

  20. Profile Distribution of Exchangeable Cations under No-till and Conventional Tillage in An Aquic Brown Soil%免耕与常规耕作潮棕壤交换性阳离子的剖面分布特征

    Institute of Scientific and Technical Information of China (English)

    孙良杰; 张晓珂; 梁文举

    2009-01-01

    The effects of tillage systems on exchangeable cations of different layers to a 1 m depth in an aquic brown soil were studied in a field experiment. The results showed that no-tillage, compared with conventional tillage, significantly increased soil pH and reduced electronic conductivity (EC) in the 0- 5 cm layer. Soil exchangeable K~+ was improved in no-tillage treatment,while exchangeable Na was declined. However, there was no significant effect of tillage practices on soil exchangeable Ca~(2+) , Mg~(2+) and cation exchange capacity. Correlation analysis showed that no significant correlations were observed between exchangeable K and soil nutrients, whereas exchangeable Na~+ , Ca~(2+) , Mg~(2+) , as well as cation exchange capacity had significant negative correlations with organic matter (OM) and total nitrogen (TN), respectively.%通过田间定位试验.研究了不同耕作方式对潮棕壤0-100 cm深度6个土层土壤交换性阳离子的影响.结果表明,与常规耕作相比,免耕使土壤表层pH显著增,.而电导率下降;同时,免耕增加了表层土壤可交换性K~+含量,降低了可交换性Na~+含量,但对可交换性Ca~(2+),Mg~(2+)和阳离子交换量没有产生显著影响.相关分析结果表明,可交换性K~+与土壤养分含量没有显著相关性,而可交换性Na~+,Ca~(2+),Mg~(2+)和阳离子交换量与有机质和全氮含量均呈负相关关系.

  1. What is the economy of Ancien Regime?

    OpenAIRE

    Jean-Yves Grenier

    2012-01-01

    The aim of this article is to describe the main features of the Ancien Regime economy and develop a “political economy” of European societies, particularly the French, during the central period of modernity (XVII-XVIII centuries

  2. Earth Regime Network Evolution Study (ERNESt)

    Science.gov (United States)

    Menrad, Bob

    2016-01-01

    Speaker and Presenter at the Lincoln Laboratory Communications Workshop on April 5, 2016 at the Massachusetts Institute of Technology Lincoln Laboratory in Lexington, MA. A visual presentation titled Earth Regimes Network Evolution Study (ERNESt).

  3. FLOW REGIMES BELOW AERATORS FOR DISCHARGE TUNNELS

    Institute of Scientific and Technical Information of China (English)

    MA Fei; WU Jian-hua

    2012-01-01

    The flow regimes below an aerator influence directly the air entrainment and the cavitation damage control.Based on the theoretical considerations,the experiments of the aerator for a discharge tunnel were conducted,and the relationships between the flow regime and hydraulic and geometric parameters were investigated.The results showed that,there are two kinds of threshold values for the flow regime conversions.One is Fr1-2 standing for the conversion from the fully filled cavity to the partially filled cavity,and the other is Fr2-3 which shows the change from the partially filled cavity to the net air cavity.Two empirical expressions were obtained for the conversions of the flow regimes,which can be used in the designs of the aerators.

  4. The Two Regimes of Postwar Shipping

    DEFF Research Database (Denmark)

    Iversen, Martin Jes; Tenold, Stig

    2014-01-01

    the bargaining that accompanied the shift from the national regime to the competitive regime. Specifically, we show that the new regime primarily accommodated the interests of private actors such as shipping companies, rather than the interests of the authorities and the trade unions.......The aim of this article is to illustrate the most important changes in the regulatory framework of the shipping sector from the 1960s to 2010, and to analyse the basis for, and effects of, these changes. In order to explain how the transformation has occurred, we use two traditional maritime...... nations—Denmark and Norway—as case studies. First, we introduce the two regimes of Danish and Norwegian shipping: ‘the national regime’ from the early 1960s to the mid-1970s; and ‘the competitive regime’, which was fully established by the middle of the 1990s and still persists. Then, we briefly sketch...

  5. Regimes of validity for balanced models

    Science.gov (United States)

    Gent, Peter R.; McWilliams, James C.

    1983-07-01

    Scaling analyses are presented which delineate the atmospheric and oceanic regimes of validity for the family of balanced models described in Gent and McWilliams (1983a). The analyses follow and extend the classical work of Charney (1948) and others. The analyses use three non-dimensional parameters which represent the flow scale relative to the Earth's radius, the dominance of turbulent or wave-like processes, and the dominant component of the potential vorticity. For each regime, the models that are accurate both at leading order and through at least one higher order of accuracy in the appropriate small parameter are then identified. In particular, it is found that members of the balanced family are the appropriate models of higher-order accuracy over a broad range of parameter regimes. Examples are also given of particular atmospheric and oceanic phenomena which are in the regimes of validity for the different balanced models.

  6. The international climate regime: towards consolidation collapse

    International Nuclear Information System (INIS)

    This article deals with the different modalities that exist to manage a problem of collective action in the field of climate negotiation. It uses two concepts of the International Political Economy (IPE): the concept of International Regime (IR) and the concept of Hegemony and / or Leadership. The course the international negotiation has taken between 1992 (Rio Convention) and march 2001 (the US rejection of the Kyoto Protocol of 1997) leads us, first, to question the conditions of existence as well as the viability of a non-hegemonic International Regime (Part One). Then, we discuss the perspectives for the 'post - Kyoto' era. After having examined the preferences of the three most active actors in the negotiation (USA, Europe, G77 + China) combined with the leadership capacities they possess, we identify three scenarios for the future: i) anarchy, ii) an international regime under the American hegemony, iii) an international regime under the European leadership (Part Two). (author)

  7. Developmental Regimes in Africa synthesis report

    OpenAIRE

    Booth, D.; Dietz, A.J.; Golooba-Mutebi, F.; Fuady, A.H.; Henley, D; Kelsall, T.; Leliveld, A.H.M.; Donge, van, J.K.

    2015-01-01

    Many African countries have experienced sustained economic growth, but few have achieved the type of structural change, driven by rising productivity, that has transformed mass living standards in parts of Asia. In the Developmental Regimes in Africa Synthesis Report, editor David Booth examines how DRA research has shed new light on how developmental regimes might emerge and be sustained in Africa in the 21st century. He outlines a concept with defining features at three levels: policy conte...

  8. Regime shifts and inflation uncertainty in Peru

    OpenAIRE

    Paúl Castillo; Alberto Humala; Vicente Tuesta

    2012-01-01

    The link between inflation and inflation uncertainty is evaluated using Peruvian data, in a context of changing monetary policies because of regime shifts. A Markov regime-switching heteroskedasticity model that includes unobserved components is used. The model shows how periods of high (low) inflation accompany periods of high (low) short- and long-run uncertainty in inflation. The results of the model also illustrate how, during the recent period of price stability in Peru, both permanent a...

  9. Regime Diagrams for K-Theory Dispersion

    Science.gov (United States)

    Smith, Ronald B.

    2011-06-01

    In atmospheric dispersion, the "non-Gaussian" effects of gravitational settling, the vertical gradient in diffusivity and the surface deposition do not enter uniformly but rather break up parameter space into several discrete regimes. Here, we describe regime diagrams that are constructed for K-theory dispersion of effluent from a surface line source in unsheared inhomogeneous turbulence, using a previously derived Fourier-Hankel method. This K-theory formulation differs from the traditional one by keeping a non-zero diffusivity at the ground. This change allows for turbulent exchange between the canopy and the atmosphere and allows new natural length scales to emerge. The axes on the regime diagrams are non-dimensional distance defined as the ratio of downwind distance to the characteristic length scale for each effect. For each value of the ratio of settling speed to the K gradient, two to four regimes are found. Concentration formulae are given for each regime. The regime diagrams allow real dispersion problems to be categorized and the validity of end-state concentration formulae to be judged.

  10. Laser-Nucleus Interactions: The Quasiadiabatic Regime

    CERN Document Server

    Pálffy, Adriana; Hoefer, Axel; Weidenmüller, Hans A

    2015-01-01

    The interaction between nuclei and a strong zeptosecond laser pulse with coherent MeV photons is investigated theoretically. We provide a first semi-quantitative study of the quasiadiabatic regime where the photon absorption rate is comparable to the nuclear equilibration rate. In that regime, multiple photon absorption leads to the formation of a compound nucleus in the so-far unexplored regime of excitation energies several hundred MeV above the yrast line. The temporal dynamics of the process is investigated by means of a set of master equations that account for dipole absorption, stimulated dipole emission, neutron decay and induced fission in a chain of nuclei. That set is solved numerically by means of state-of-the-art matrix exponential methods also used in nuclear fuel burnup and radioactivity transport calculations. Our quantitative estimates predict the excitation path and range of nuclei reached by neutron decay and provide relevant information for the layout of future experiments.

  11. Fermi's golden rule beyond the Zeno regime

    Science.gov (United States)

    Debierre, Vincent; Goessens, Isabelle; Brainis, Edouard; Durt, Thomas

    2015-08-01

    We reconsider the problem of the spontaneous emission of light by an excited atomic state. We scrutinize the survival probability of this excited state for very short times, in the so-called Zeno regime, for which we show that the dynamics is dictated by a coherent, in-phase, response of the on-shell and off-shell vacuum modes. We also develop a perturbative approach in order to interpolate between different temporal regimes: the Zeno, golden rule (linear), and Wigner-Weisskopf (exponential) regimes. We compare results obtained with the E ̂.x ̂ and A ̂.p ̂ interaction Hamiltonians, using successively the dipole approximation and the exact coupling.

  12. Interpreting MAD within multiple accretion regimes

    CERN Document Server

    Mocz, Philip

    2014-01-01

    General relativistic magnetohydrodynamic (GRMHD) simulations of accreting black holes in the radiatively inefficient regime show that systems with sufficient magnetic poloidal flux become magnetically arrested disc (MAD) systems, with a well-defined relationship between the magnetic flux and the mass accretion rate. Recently, Zamaninasab (2014) report that the jet magnetic flux and accretion disc luminosity are tightly correlated over 7 orders of magnitude for a sample of 76 radio-loud active galaxies, concluding that the data are explained by the MAD mode of accretion. Their analysis assumes radiatively efficient accretion, and their sample consists primarily of radiatively efficient sources, while GRMHD simulations of MAD thus far have been carried out in the radiatively inefficient regime. We propose a model to interpret MAD systems in the context of multiple accretion regimes, and apply it to the sample in Zamaninasab (2014), along with additional radiatively inefficient sources from archival data. We sho...

  13. Regimes of turbulence without an energy cascade

    CERN Document Server

    Barenghi, C F; Baggaley, A W

    2016-01-01

    Experiments and numerical simulations of turbulent $^4$He and $^3$He-B have established that, at hydrodynamic length scales larger than the average distance between quantum vortices, the energy spectrum obeys the same 5/3 Kolmogorov law which is observed in the homogeneous isotropic turbulence of ordinary fluids. The importance of the 5/3 law is that it points to the existence of a Richardson energy cascade from large eddies to small eddies. However, there is also evidence of quantum turbulent regimes without Kolmogorov scaling. This raises the important questions of why, in such regimes, the Kolmogorov spectrum fails to form, what is the physical nature of turbulence without energy cascade, and whether hydrodynamical models can account for the unusual behaviour of turbulent superfluid helium. In this work we describe simple physical mechanisms which prevent the formation of Kolmogorov scaling in the thermal counterflow, and analyze the conditions necessary for emergence of quasiclassical regime in quantum tu...

  14. Early detection of ecosystem regime shifts

    DEFF Research Database (Denmark)

    Lindegren, Martin; Dakos, Vasilis; Groeger, Joachim P.;

    2012-01-01

    Critical transitions between alternative stable states have been shown to occur across an array of complex systems. While our ability to identify abrupt regime shifts in natural ecosystems has improved, detection of potential early-warning signals previous to such shifts is still very limited...... methods may have limited utility in ecosystem-based management as they show no or weak potential for early-warning. We therefore propose a multiple method approach for early detection of ecosystem regime shifts in monitoring data that may be useful in informing timely management actions in the face....... Using real monitoring data of a key ecosystem component, we here apply multiple early-warning indicators in order to assess their ability to forewarn a major ecosystem regime shift in the Central Baltic Sea. We show that some indicators and methods can result in clear early-warning signals, while other...

  15. Determination of the Hall Thruster Operating Regimes

    Energy Technology Data Exchange (ETDEWEB)

    L. Dorf; V. Semenov; Y. Raitses; N.J. Fisch

    2002-04-09

    A quasi one-dimensional (1-D) steady-state model of the Hall thruster is presented. For the same discharge voltage two operating regimes are possible -- with and without the anode sheath. For given mass flow rate, magnetic field profile and discharge voltage a unique solution can be constructed, assuming that the thruster operates in one of the regimes. However, we show that for a given temperature profile the applied discharge voltage uniquely determines the operating regime: for discharge voltages greater than a certain value, the sheath disappears. That result is obtained over a wide range of incoming neutral velocities, channel lengths and widths, and cathode plane locations. It is also shown that a good correlation between the quasi 1-D model and experimental results can be achieved by selecting an appropriate electron mobility and temperature profile.

  16. Regimes, Non-State Actors and the State System: A 'Structurational' Regime Model

    NARCIS (Netherlands)

    Arts, B.J.M.

    2000-01-01

    Regime analysis has become a popular approach in International Relations theory and in international policy studies. However, current regime models exhibit some shortcomings with regard to (1) addressing non-state actors, and in particular nongovernmental organizations (NGOs), (2) the balancing of a

  17. Causas estruturais e consequências dos regimes internacionais: regimes como variáveis intervenientes

    Directory of Open Access Journals (Sweden)

    Stephen D. Krasner

    2012-06-01

    Full Text Available Os regimes internacionais são definidos como princípios, normas, regras e procedimentos de tomada de decisões ao redor dos quais as expectativas dos atores convergem em uma dada área-tema. Como ponto de partida, os regimes são conceituados como variáveis intervenientes, estando entre fatores causais básicos e os resultados e comportamentos relacionados. Há três visões a respeito da importância dos regimes: as orientações estruturais convencionais desvalorizam os regimes como sendo, na melhor das hipóteses, ineficazes; as orientações grocianas vêem os regimes como componentes íntimos do sistema internacional; as perspectivas estruturalistas modificadas vêem os regimes como significativos somente em certas condições restritas. Para os argumentos grociano e estruturalista modificado - que concordam com a visão de que os regimes podem influenciar resultados e comportamentos - , o desenvolvimento de regimes é visto como uma função de cinco variáveis causais básicas: auto-interesse egoísta; poder político; normas e princípios difusos; usos e costumes; conhecimento.

  18. Supercurrent in the quantum Hall regime.

    Science.gov (United States)

    Amet, F; Ke, C T; Borzenets, I V; Wang, J; Watanabe, K; Taniguchi, T; Deacon, R S; Yamamoto, M; Bomze, Y; Tarucha, S; Finkelstein, G

    2016-05-20

    A promising route for creating topological states and excitations is to combine superconductivity and the quantum Hall (QH) effect. Despite this potential, signatures of superconductivity in the QH regime remain scarce, and a superconducting current through a QH weak link has been challenging to observe. We demonstrate the existence of a distinct supercurrent mechanism in encapsulated graphene samples contacted by superconducting electrodes, in magnetic fields as high as 2 tesla. The observation of a supercurrent in the QH regime marks an important step in the quest for exotic topological excitations, such as Majorana fermions and parafermions, which may find applications in fault-tolerant quantum computing. PMID:27199424

  19. Economic performance and North Korean regime legitimacy

    OpenAIRE

    Moore, Patrick J.

    2014-01-01

    This thesis examines the sources of legitimacy for the North Korean regime in an effort to explain what role, if any, economic performance has played in keeping the Kim family in power. This thesis provides a historical look at the development of the North Korean regime from the beginning under Kim Il-sung to the current generation of rule under Kim Jong-un. The core argument of the thesis is broken into two major time periods, with the economic downturn of the early 1990s serving as the divi...

  20. WELFARE REGIMES IN LATIN AMERICA AND CARIBBEAN

    Directory of Open Access Journals (Sweden)

    Melisa Campana-Alabarce

    2015-06-01

    Full Text Available This article provides a characterization of Latin American and Caribbean Welfare regimes in historiographical perspective. Firstly, it makes a review of the emergence conditions of Welfare States in Western Europe and its core features, with particular emphasis on its role as a method to regulate inequalities in industrial capitalism. Dialoguing with it, then stops in the specific configurations that welfare regimes have taken in Latin America during the course of the twentieth century. Finally, it provides a map of its contemporary features and the major challenges that the States of the region face in his capacity as right guarantors for the future.

  1. Light focusing in the Anderson Regime

    CERN Document Server

    Leonetti, Marco; Mafi, Arash; Conti, Claudio

    2014-01-01

    Anderson localization is a regime in which diffusion is inhibited and waves (also electromagnetic waves) get localized. Here we exploit adaptive optics to achieve focusing in disordered optical fibers in the Anderson regime. By wavefront shaping and optimization, we observe the generation of a propagation invariant beam, where light is trapped transversally by disorder, and show that Anderson localizations can be also excited by extended speckled beams. We demonstrate that disordered fibers allow a more efficient focusing action with respect to standard fibers in a way independent of their length, because of the propagation invariant features and cooperative action of transverse localizations.

  2. Synchronization regimes in conjugate coupled chaotic oscillators.

    Science.gov (United States)

    Karnatak, Rajat; Ramaswamy, Ram; Prasad, Awadhesh

    2009-09-01

    Nonlinear oscillators that are mutually coupled via dissimilar (or conjugate) variables display distinct regimes of synchronous behavior. In identical chaotic oscillators diffusively coupled in this manner, complete synchronization occurs only by chaos suppression when the coupled subsystems drive each other into a regime of periodic dynamics. Furthermore, the coupling does not vanish but acts as an "internal" drive. When the oscillators are mismatched, phase synchronization occurs, while in a master slave configuration, generalized synchrony results. These effects are demonstrated in a system of coupled chaotic Rossler oscillators.

  3. Supercurrent in the quantum Hall regime

    Science.gov (United States)

    Amet, F.; Ke, C. T.; Borzenets, I. V.; Wang, J.; Watanabe, K.; Taniguchi, T.; Deacon, R. S.; Yamamoto, M.; Bomze, Y.; Tarucha, S.; Finkelstein, G.

    2016-05-01

    A promising route for creating topological states and excitations is to combine superconductivity and the quantum Hall (QH) effect. Despite this potential, signatures of superconductivity in the QH regime remain scarce, and a superconducting current through a QH weak link has been challenging to observe. We demonstrate the existence of a distinct supercurrent mechanism in encapsulated graphene samples contacted by superconducting electrodes, in magnetic fields as high as 2 tesla. The observation of a supercurrent in the QH regime marks an important step in the quest for exotic topological excitations, such as Majorana fermions and parafermions, which may find applications in fault-tolerant quantum computing.

  4. Anomalous Hall effect in localization regime

    Science.gov (United States)

    Wu, Lin; Zhu, Kai; Yue, Di; Tian, Yuan; Jin, Xiaofeng

    2016-06-01

    The anomalous Hall effect in the ultrathin film regime is investigated in Fe(001)(1-3 nm) films epitaxial on MgO(001). The logarithmic localization correction to longitudinal resistivity and anomalous Hall resistivity are observed at low temperature. We identify that the coefficient of skew scattering has a reduction from metallic to localized regime, while the contribution of side jump has inconspicuous change except for a small drop below 10 K. Furthermore, we discover that the intrinsic anomalous Hall conductivity decreases with the reduction of thickness below 2 nm. Our results provide unambiguous experimental evidence to clarify the problem of localization correction to the anomalous Hall effect.

  5. The oil tax regime of Azerbaijan

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Gerard

    1998-07-01

    Azerbaijan has a long history in the oil business and a chance of a spectacular future. To understand why the oil tax regime evolved into its present form and how it is likely to develop, it is necessary to know something of the country's history and the commercial environment. Consequently the presentation begins by discussing these items. It then outlines the Production Sharing Agreement regime in Azerbaijan and then deals with the Kazakh and Georgian Tax Codes, as these are likely to be the basis of a new general tax law in Azerbaijan from 1999. The presentation includes comments on the New Draft Tax Code of 1998.

  6. Regimes of flow past a vortex generator

    DEFF Research Database (Denmark)

    Velte, Clara Marika; Okulov, V.L.; Naumov, I.V.

    2012-01-01

    particle image velocimetry (SPIV). Based on the obtained SPIV data, a map of the regimes of flow past the vortex generator has been constructed. One region with a developed stable multivortex system on this map reaches the vicinity of the optimum angle of attack of the vortex generator....

  7. In Search of the Chiral Regime

    CERN Document Server

    Beane, S R

    2004-01-01

    A critical appraisal is given of a recent analysis of the quark-mass and finite-size dependence of unquenched lattice QCD data for the nucleon mass. We use this forum to estimate the boundary of the chiral regime for nucleon properties.

  8. Optimal dividend distribution under Markov regime switching

    NARCIS (Netherlands)

    Z. Jiang; M. Pistorius

    2012-01-01

    We investigate the problem of optimal dividend distribution for a company in the presence of regime shifts. We consider a company whose cumulative net revenues evolve as a Brownian motion with positive drift that is modulated by a finite state Markov chain, and model the discount rate as a determini

  9. European welfare regimes: Political orientations versus poverty

    Directory of Open Access Journals (Sweden)

    Josifidis Kosta

    2011-01-01

    Full Text Available This inquiry analyzes how political orientations shape welfare states and labour market institutions when seeking to reduce poverty. In order to identify effects of these two key variables, we conduct a panel regression analysis that includes two poverty measures: poverty rates before and after social spending. This inquiry considers 14 EU countries, and in the period from 1995 to 2008, which are grouped according to welfare state regimes. We consider Social Democratic, Corporatist, Mediterranean and Liberal welfare state regimes. Panel regression results indicate that political orientation engenders no significant statistically measurable effects on poverty rates before social spending. Effects register, however, as significant when considering poverty rates after social spending. With respect to the first set of results, we advance two key explanations. First, we note a longer period of time is necessary in order to observe actual effects of political orientation on market generated poverty. Second, political parties with their respective programs do not register as influential enough to solve social problems related to income distribution when taken alone. Influences register as indirect and are expressed through changes in employment rates and social spending. The second set of results support the hypothesis that a selected political regime does indeed contribute to poverty reduction. In sum, political orientation and political regime does indeed affect poverty through welfare state institutions, as well as through labour market institutions.

  10. Estimation in autoregressive models with Markov regime

    OpenAIRE

    Ríos, Ricardo; Rodríguez, Luis

    2005-01-01

    In this paper we derive the consistency of the penalized likelihood method for the number state of the hidden Markov chain in autoregressive models with Markov regimen. Using a SAEM type algorithm to estimate the models parameters. We test the null hypothesis of hidden Markov Model against an autoregressive process with Markov regime.

  11. A Comparative Typology of Pension Regimes

    NARCIS (Netherlands)

    Arjan Soede; Cok Vrooman

    2008-01-01

    This report presents an empirical typology of pension regimes in the European Union, the US, Canada, Australia and Norway. The categorisation is based on 34 quantitative and qualitative characteristics of the mandatory parts of the pension systems in these countries. The empirical analysis shows tha

  12. Developmental Regimes in Africa synthesis report

    NARCIS (Netherlands)

    Booth, D.; Dietz, A.J.; Golooba-Mutebi, F.; Fuady, A.H.; Henley, D.; Kelsall, T.; Leliveld, A.H.M.; Donge, van J.K.

    2015-01-01

    Many African countries have experienced sustained economic growth, but few have achieved the type of structural change, driven by rising productivity, that has transformed mass living standards in parts of Asia. In the Developmental Regimes in Africa Synthesis Report, editor David Booth examines how

  13. Radiative effects of global MODIS cloud regimes

    Science.gov (United States)

    Oreopoulos, Lazaros; Cho, Nayeong; Lee, Dongmin; Kato, Seiji

    2016-03-01

    We update previously published Moderate Resolution Imaging Spectroradiometer (MODIS) global cloud regimes (CRs) using the latest MODIS cloud retrievals in the Collection 6 data set. We implement a slightly different derivation method, investigate the composition of the regimes, and then proceed to examine several aspects of CR radiative appearance with the aid of various radiative flux data sets. Our results clearly show that the CRs are radiatively distinct in terms of shortwave, longwave, and their combined (total) cloud radiative effect. We show that we can clearly distinguish regimes based on whether they radiatively cool or warm the atmosphere, and thanks to radiative heating profiles, to discern the vertical distribution of cooling and warming. Terra and Aqua comparisons provide information about the degree to which morning and afternoon occurrences of regimes affect the symmetry of CR radiative contribution. We examine how the radiative discrepancies among multiple irradiance data sets suffering from imperfect spatiotemporal matching depend on CR and whether they are therefore related to the complexity of cloud structure, its interpretation by different observational systems, and its subsequent representation in radiative transfer calculations.

  14. De facto and official exchange rate regimes in transition economies

    OpenAIRE

    von Hagen, Jürgen; Zhou, Jizhong

    2002-01-01

    This paper provides an empirical investigation on the discrepancies between official exchange rate regimes and de facto exchange rate policies in transition economies. Since official and de facto regime choices are not independent of each other, we adopt a bivariate probit model to describe the joint determination of the two regime choices. After finding the important determinants of both regime choices, we use a univariate probit model to describe the determination of regime discrepancies. W...

  15. The Effect of Market Regimes on Style Allocation

    OpenAIRE

    Ammann, Manuel; Verhofen, Michael

    2006-01-01

    We analyse time-varying risk premia and the implications for portfolio choice. Using Markov Chain Monte Carlo (MCMC) methods, we estimate a multivariate regime-switching model for the Carhart (1997) four factor model. We find two clearly separable Regimes with different mean returns, volatilities and correlations. In the High-Variance Regime, only value stocks deliver a good performance, whereas in the Low-Variance Regime, the market portfolio and momentum stocks promise high returns. Regime-...

  16. Regime shifts in the anthropocene: drivers, risks, and resilience.

    Science.gov (United States)

    Rocha, Juan Carlos; Peterson, Garry D; Biggs, Reinette

    2015-01-01

    Many ecosystems can experience regime shifts: surprising, large and persistent changes in the function and structure of ecosystems. Assessing whether continued global change will lead to further regime shifts, or has the potential to trigger cascading regime shifts has been a central question in global change policy. Addressing this issue has, however, been hampered by the focus of regime shift research on specific cases and types of regime shifts. To systematically assess the global risk of regime shifts we conducted a comparative analysis of 25 generic types of regime shifts across marine, terrestrial and polar systems; identifying their drivers, and impacts on ecosystem services. Our results show that the drivers of regime shifts are diverse and co-occur strongly, which suggests that continued global change can be expected to synchronously increase the risk of multiple regime shifts. Furthermore, many regime shift drivers are related to climate change and food production, whose links to the continued expansion of human activities makes them difficult to limit. Because many regime shifts can amplify the drivers of other regime shifts, continued global change can also be expected to increase the risk of cascading regime shifts. Nevertheless, the variety of scales at which regime shift drivers operate provides opportunities for reducing the risk of many types of regime shifts by addressing local or regional drivers, even in the absence of rapid reduction of global drivers. PMID:26267896

  17. 长期不同施肥方式对砷在典型壤质潮土及作物中累积的影响%Effects of long-term fertilization on As (arsenate) accumulation in typical fluvo-aquic soils and crops

    Institute of Scientific and Technical Information of China (English)

    王擎运; 张佳宝; 信秀丽; 赵炳梓; 邓西海; 钦绳武

    2012-01-01

    Huang-Huai-Hai Plain is a strategic grain production base in China with a wild distribution of fertile fluvo-aquic soils. During the past 20 years, high-input intensive agriculture with excess chemical fertilizer application has sustained high grain yields. However, unreasonable field management has resulted in potential pollution issues in the plain. In this study, the effects of long-term differential fertilization practices on the accumulation of arsenate (As) in typical fluvo-aquic soils and crops were investigated. Field experiments were launched in 1989, in which 7 treatments were established. The treatments included OM (organic manure), OM+NPK (50% organic manure + 50% chemical fertilizer), NPK, NP, PK, NK and CK (the control experiment with no fertilizer). With over 20 years (1989-2009) of cultivation, As in the surface (0~20 cm) and subsurface (20~40 cm) soil layers markedly accumulated. The soil As content was, however, too low for loading negative effects on eco-agricultural safety. As accumulation in the plain was mainly affected by irrigation and deposition, and relatively less affected by different fertilizer applications. The content of As in phosphorus (P) fertilizers was higher than in nitrogen (N) and potassium (K) fertilizers or in organic manure (OM). Hence P fertilization was the main drive of soil As accumulation in the plain. Nevertheless, long-term P fertilization did not significantly increase soil As content since it was largely used up by crops. Also As accumulation trend slowed with OM fertilization. Crop tissue content of As was in the order of root > stalk > grain. Grain As content was not only significantly lower than that of root or stalk, but also than that of China's national standard. For different fertilization treatments, wheat tissue As content was in the order of PK > OM > OM+NPK > NPK > NP > NK > CK. This was somehow similar to that of soil available P, which was indirectly affected by soil organic matter content. Under OM

  18. Effects of long-term K application and straw returning on crop yield and soil K status in fluvo-aquic soil of Hebei Province%长期施钾和秸秆还田对河北潮土区作物产量和土壤钾素状况的影响

    Institute of Scientific and Technical Information of China (English)

    孙丽敏; 李春杰; 何萍; 刘孟朝; 胡景辉

    2012-01-01

    以河北冲积平原典型潮土区小麦-玉米轮作长期定位试验(19922009年)为基础,分析了长期施用钾肥和秸秆还田对作物产量、 土壤钾含量及钾素平衡的影响。研究结果表明,不同处理下小麦、 玉米17年平均产量均表现为NPKSt〉NPK〉NPSt〉NP,其中,小麦、 玉米NPKSt处理比NP处理分别增产9.37%和19.23%,NPK处理比NP处理分别增产6.32%和18.25%; NPSt处理比NP处理分别增产2.76%和9.60%; 长期定位施肥下,各处理耕层土壤(0—20 cm)各施钾肥的处理其速效钾、 缓效钾含量均与NP处理差异极显著,且表现为NPKSt〉NPK〉NPSt〉NP; 各处理下层土壤(20—40 cm)的速效钾、 缓效钾含量差异均不显著,从钾素平衡看,NP处理钾素表观年盈亏量为-170.0 kg/hm2,土壤钾严重亏缺; NPSt处理实际平衡盈亏率-58.4%,表观年盈亏量为-150.6 kg/hm2; NPK处理钾素表观年盈亏量-3.1 kg/hm2,盈亏率-1.0%,基本接近平衡; NPKSt处理实际平衡盈亏率36.8%,表观年盈亏量为111.4 kg/hm2。试验结果说明,在潮土区,在施氮、 磷肥的基础上,配施钾肥或秸秆还田不仅能持续提高小麦、 玉米的高产、 稳产生产能力, 而且对保持农田土壤钾素平衡、 有效改善耕层土壤钾素状况、 提高土壤肥力有重要的作用。%With the aim to provide the theoretical basis for sustainably increasing crop yield, productivity, and nutrient management in fluvoaquic soil of Hebei Province, the effects of the longterm application of K fertilizers and straw returning on crop yield, soil K content and potassium balance were analyzed using the data obtained from the longterm K localization experiment (1992-2009) under wheatmaize rotation system. The results reveal that the 17-year average yields of wheat and maize are in an order as NPKSt 〉 NPK 〉 NPSt 〉 NP, which is similar to the effects of the K fertilizer application

  19. Recent Activities on Global Nuclear Safety Regime

    International Nuclear Information System (INIS)

    Recently, rapid progress on the globalization of the nuclear safety issues is being made in IAEA (International Atomic Energy Agency) and its member states. With the globalization, the need for international cooperation among international bodies and member states continues to grow for resolving these universal nuclear safety issues. Furthermore, the importance of strengthening the global nuclear safety regime is emphasized through various means, such as efforts in application of IAEA safety standards to all nuclear installations in the world and in strengthening the code of conduct and the convention on nuclear safety. In this regards, it is important for us to keep up with the activities related with the global nuclear safety regime as an IAEA member state and a leading country in nuclear safety regulation

  20. Online recognition of the multiphase flow regime

    Institute of Scientific and Technical Information of China (English)

    BAI BoFeng; ZHANG ShaoJun; ZHAO Liang; ZHANG XiMin; GUO LieJin

    2008-01-01

    The key reasons that the present method cannot be used to solve the industrial multi-phase flow pattern recognition are clarified firstly. The prerequisite to realize the online recognition is proposed and recognition rules for partial flow pattern are obtained based on the massive experimental data. The standard templates for every flow regime feature are calculated with self-organization cluster algorithm. The multi-sensor data fusion method is proposed to realize the online recognition of multiphase flow regime with the pressure and differential pressure signals, which overcomes the severe influence of fluid flow velocity and the oil fraction on the recognition. The online recognition method is tested in the practice, which has less than 10 percent measurement error. The method takes advantages of high confidence, good fault tolerance and less requirement of single sensor performance.

  1. Online recognition of the multiphase flow regime

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The key reasons that the present method cannot be used to solve the industrial multi- phase flow pattern recognition are clarified firstly. The prerequisite to realize the online recognition is proposed and recognition rules for partial flow pattern are obtained based on the massive experimental data. The standard templates for every flow regime feature are calculated with self-organization cluster algorithm. The multi-sensor data fusion method is proposed to realize the online recognition of multiphase flow regime with the pressure and differential pressure signals, which overcomes the severe influence of fluid flow velocity and the oil fraction on the recognition. The online recognition method is tested in the practice, which has less than 10 percent measurement error. The method takes advantages of high confidence, good fault tolerance and less requirement of single sensor performance.

  2. Regimes de espaço

    Directory of Open Access Journals (Sweden)

    Eric Landowski

    2015-06-01

    Full Text Available Space Regimes - Based on a general model of interaction, the present analysis attempts to account for the diversity of the ways space may be apprehended in lived experience. It leads to the definition of four configurations that correspond to as many regimes of relation with the environing world. The conventional space of the circulation of values takes the archetypical shape of the net (incarnated today by Internet. The operational space is that of our dealing with objects within a material environment seen as a tissue of stable and intelligible relations. The experienced space of bodies’ movement, to which one may give as an emblem the spiral, expresses the dynamics of sensitive relationships between the self and the other. The existential space is that of our presence in a universe without boundaries, which no one can properly represent oneself but that nonetheless haunts art and thought: its figure is the abyss.

  3. Deuteron structure in the deep inelastic regime

    CERN Document Server

    Canal, C A Garcìa; Vento, V

    2016-01-01

    We study nuclear effects on the deuteron in the deep inelastic regime using the newest available data analyzing their $Q^2$ dependence. We conclude that precise EMC ratios for large $Q^2$ (> 30, GeV$^2$) cannot be obtained without considering these nuclear effects. For this purpose we use a scheme which parametrizes these effects in a simple manner and compare our results with other recent proposals.

  4. The Forex Regime and EMU Expansion

    OpenAIRE

    Foreest, P.W.; de Vries, Casper

    2002-01-01

    This paper provides evidence that the choice of the foreign exchange regime is not of first order importance for achieving high output growth. It is argued that due to the forward looking nature of the foreign exchange market, exchange rate stability hinges on the current and anticipated coherency of monetary and fiscal policies. We demonstrate this empirically on a panel including potential EMU accession countries. By means of rank regression analysis we uncover the partial links across the ...

  5. Dynamic Regime of Ignition of Solid Propellant

    Directory of Open Access Journals (Sweden)

    Zolotorev Nikolay

    2016-01-01

    Full Text Available This article presents a dynamic regime of exposure of the radiant flux on the sample of gun-cotton. Obtained time the ignition of gun-cotton in the heating conditions of increasing heat flux in the range from 0.2 W/cm2 to 22 W/cm2. A comparison of the delay times of the ignition when heated variable and constant heat flux.

  6. Exchange Rate Regimes and International Business Cycles

    OpenAIRE

    Theptida Sopraseuth

    2003-01-01

    This paper investigates the impact of exchange rate regimes on international business cycles and focuses on the consequences of membership to the European Monetary System. The volatility puzzle uncovered by Baxter and Stockman [1989, Journal of Monetary Economics 23, 377–401] after assessing the consequences of the Bretton Woods system turns out to be a robust stylized fact: real and nominal exchange rates display a higher volatility under floating rates while the variability of macroeconom...

  7. APPLICABLE LAW PRINCIPLES FOR MATRIMONIAL PROPERTY REGIMES

    OpenAIRE

    Andreea-Lorena CODREANU

    2014-01-01

    More and more often, marriages are concluded between people of different nationalities, which brings an extraneous dimension to the legal status and matrimonial property regime jurisdiction conflict. Many European states (among which Romania, through its new Civil Code) offer the advantage of clauses that could be used by any of the spouses, with regard to the applicable law. In case of divorce, consequences differ with the applicable law. Spouses who divorce and divide their assets based on ...

  8. Monetary policy regimes and the Nordic model

    OpenAIRE

    Schewe, Theo

    2015-01-01

    In many contexts, the Nordic countries are regarded as a natural bloc of nations that have common political, cultural and economic characteristics. Open to globalisation, the small Nordic countries are exposed to strong global competition and cyclical influences. Therefore, the basis of the model may be to combine collective risk sharing and openness to globalisation. Studies of the Nordic model do not focus on the question whether the monetary policy regime is a constitutive element of the m...

  9. Financing welfare regimes: mapping heterogeneous revenue structures

    OpenAIRE

    Gough, Ian; Abu-Sharkh, Miriam

    2011-01-01

    This article studies how the composition of public revenues in terms of sources (such as taxation, social insurance contributions, mineral rents, foreign aid) is associated with different welfare regimes and social policy outcomes. It is divided into two halves: a review of literature and research, and a cross-national data analysis. The first half reviews literature on the emergence of tax and revenue systems in the West, and on the relevance of these frameworks and findings to developing co...

  10. Snowpack regimes of the Western United States

    OpenAIRE

    Trujillo, Ernesto; Molotch, Noah P.

    2014-01-01

    Snow accumulation and melt patterns play a significant role in the water, energy, carbon, and nutrient cycles in the montane environments of the Western United States. Recent studies have illustrated that changes in the snow/rainfall apportionments and snow accumulation and melt patterns may occur as a consequence of changes in climate in the region. In order to understand how these changes may affect the snow regimes of the region, the current characteristics of the snow accumulation and mel...

  11. Tax incentive regimes: models and research methods

    OpenAIRE

    Sokolovska, Olena; Sokolovskyi, Dmytro

    2014-01-01

    Paper deals with problem of effectiveness of tax incentive regimes. Support of priority industries remains currently important for transition economies. At once, such countries more often than developed ones face the imperfection of tax incentive mechanisms. Notably, such problems are common to Ukrainian and Moldavian economies, where the legislative support or its implementation in the area of preferential taxation of innovative enterprises which contribute essentially to sustainable develop...

  12. Macro Regime and Economic Growth in China

    OpenAIRE

    Yuwen Dai

    2007-01-01

    In this paper, we investigate the relationship between Chinese macroeconomic policy and economic growth, and examine how the choice of macroeconomic regime affects economic performance in China. An open-economy model is developed for this purpose. It is a three-sector “almost small" open-economy macroeconomic model, with asset markets and forward-looking agents. This open-economy model is then adopted to analyse the implications of both domestic and external growth shocks to the Chinese econo...

  13. Exchange Rate Regimes, Location, and Specialization

    OpenAIRE

    Luca Antonio Ricci

    2006-01-01

    This paper investigates the effects of fixed versus flexible exchange rates on firms' location choices and on countries' specialization patterns. In a two-country, twodifferentiated-goods monetary model, uncertainty arises after wages are set and prices are optimally chosen. The paper shows that countries are more specialized under flexible than fixed rates, which indicates that the pattern of specialization is not uniquely defined by trade models but also depends on the exchange rate regime....

  14. British Columbia's new coalbed methane royalty regime

    International Nuclear Information System (INIS)

    The British Columbia Ministry of Energy and Mines is promoting the development of the coalbed methane (CBM) industry in the province in order to make CBM a viable and competitive investment option for industry. It is establishing a regulatory and fiscal regime for CBM development. Issues of concern regarding CBM development include water production, gas production rates, well numbers, and marginal economics. The features of the CBM royalty regime include a new producer cost of service allowance, the creation of a CBM royalty tax bank to collect excess PCOS allowances, and a royalty tax credit for wells drilled by the end of February, 2004. The marginal well adjustment factor threshold has been raised from 180 mcf per day to 600 mcf per day for CBM only. It was noted that royalties will probably not be payable for several years following the first commercial well because royalties are very depending on capital and operating costs, local infrastructure and price. Royalty regimes cannot save CBM from low gas prices, poor resources or economics. 2 figs

  15. Constructing an interdisciplinary flow regime recommendation

    Science.gov (United States)

    Bartholow, J.M.

    2010-01-01

    It is generally agreed that river rehabilitation most often relies on restoring a more natural flow regime, but credibly defining the desired regime can be problematic. I combined four distinct methods to develop and refine month-by-month and event-based flow recommendations to protect and partially restore the ecological integrity of the Cache la Poudre River through Fort Collins, Colorado. A statistical hydrologic approach was used to summarize the river's natural flow regime and set provisional monthly flow targets at levels that were historically exceeded 75% of the time. These preliminary monthly targets were supplemented using results from three Poudre-specific disciplinary studies. A substrate maintenance flow model was used to better define the high flows needed to flush accumulated sediment from the river's channel and help sustain the riparian zone in this snowmelt-dominated river. A hydraulic/habitat model and a water temperature model were both used to better define the minimum flows necessary to maintain a thriving cool water fishery. The result is a range of recommended monthly flows and daily flow guidance illustrating the advantage of combining a wide range of available disciplinary information, supplemented by judgment based on ecological principles and a general understanding of river ecosystems, in a highly altered, working river. ?? 2010 American Water Resources Association.

  16. The kinetic regime of the Vicsek model

    Science.gov (United States)

    Chepizhko, A. A.; Kulinskii, V. L.

    2009-12-01

    We consider the dynamics of the system of self-propelling particles modeled via the Vicsek algorithm in continuum time limit. It is shown that the alignment process for the velocities can be subdivided into two regimes: "fast" kinetic and "slow" hydrodynamic ones. In fast kinetic regime the alignment of the particle velocity to the local neighborhood takes place with characteristic relaxation time. So, that the bigger regions arise with the velocity alignment. These regions align their velocities thus giving rise to hydrodynamic regime of the dynamics. We propose the mean-field-like approach in which we take into account the correlations between density and velocity. The comparison of the theoretical predictions with the numerical simulations is given. The relation between Vicsek model in the zero velocity limit and the Kuramoto model is stated. The mean-field approach accounting for the dynamic change of the neighborhood is proposed. The nature of the discontinuity of the dependence of the order parameter in case of vectorial noise revealed in Gregorie and Chaite, Phys. Rev. Lett., 92, 025702 (2004) is discussed and the explanation of it is proposed.

  17. Autonomia e relevância dos regimes The autonomy and relevance of regimes

    Directory of Open Access Journals (Sweden)

    Gustavo Seignemartin de Carvalho

    2005-12-01

    Full Text Available Teorias institucionalistas na disciplina de relações internacionais usualmente definem regimes como um conjunto de normas e regras formais ou informais que permitem a convergência de expectativas ou a padronização do comportamento de seus participantes em uma determinada área de interesses com o objetivo de resolver problemas de coordenação que tenderiam a resultados não pareto-eficientes. Como estas definições baseadas meramente na "eficiência" dos regimes não parecem suficientes para explicar sua efetividade, o presente artigo propõe uma definição diferente para regimes: a de arranjos políticos que permitem a redistribuição dos ganhos da cooperação pelos participantes em uma determinada área de interesses em um contexto de interdependência. Regimes possuiriam efetividade pela sua autonomia e relevância, ou seja, por possuírem existência objetiva autônoma da de seus participantes e por influenciarem seu comportamento e expectativas de maneiras que não podem ser reduzidas à ação individual de nenhum deles. O artigo inicia-se com uma breve discussão sobre as dificuldades terminológicas associadas ao estudo de regimes e a definição dos conceitos de autonomia e relevância. Em seguida, classifica os diversos autores participantes do debate em duas perspectivas distintas, uma que nega (não-autonomistas e outra que atribui (autonomistas aos regimes autonomia e relevância, e faz uma breve análise dos autores e tradições mais significativos para o debate, aprofundando-se nos autonomistas e nos argumentos que reforçam a hipótese aqui apresentada. Ao final, o artigo propõe uma decomposição analítica dos regimes nos quatro elementos principais que lhes propiciam autonomia e relevância: normatividade, atores, especificidade da área de interesses e interdependência complexa com o contexto.Regimes are defined by institutionalist theories in the discipline of International Relations as formal or informal sets

  18. Refrigeration. Two-Phase Flow. Flow Regimes and Pressure Drop

    DEFF Research Database (Denmark)

    Knudsen, Hans-Jørgen Høgaard

    2002-01-01

    The note gives the basic definitions used in two-phase flow. Flow regimes and flow regimes map are introduced. The different contributions to the pressure drop are stated together with an imperical correlation from the litterature....

  19. Asymptotic Regime in N Random Interacting Species

    CERN Document Server

    Fiasconaro, A; Valenti, D

    2005-01-01

    The asymptotic regime of a complex ecosystem with N random interacting species and in the presence of an external multiplicative noise is analyzed. We find the role of the external noise on the long time probability distribution of the i_th density species, the extinction of species and the local field acting on the i_th population. We analyze in detail the transient dynamics of this field and the cavity field, which is the field acting on the i_th species when this is absent. We find that the presence or the absence of some population give different asymptotic distributions of these fields.

  20. REVIEW OF REGIME THEORY OF ALLUVIAL CHANNELS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    One of the most important problems in river engineering is to determine a stable cross section geomenry and slope for an alluvial channel. This has been the subject of considerable research for about a century and continues to be of great practical interest. Lgnoring plan geometry, an alluvi-al channel can adjust its slope, depth and width, to develop a dynamic stable condition in which it can transport a certain a-mount of water and sediment. The brief history of regime the-ory and its new development are reviewed in this paper.

  1. Muscle's Motion in an Overdamped Regime

    Institute of Scientific and Technical Information of China (English)

    AI Bao-Quan; WANG Xian-Ju; LIU Liang-Gang; M. Nakano; H. Matsuura

    2002-01-01

    Based on the stochastic inclined rods model proposed by H. Matsuura et al., we study the motion of actin myosin system in an overdamped regime. Our model is composed ofan inclined spring (rod), a myosin head and a myosin filament. The results of calculation show that the modelcan convert the random motion to one-directional motion, and the myosin head works as a resonator of random noise, which absorbs the energy through a stochastic resonance. The results show that the inclined rod and the intermolecular potential are very important for the system to move.

  2. Autoritarismus in Peru : das Fujimori-Regime

    OpenAIRE

    Crabtree, John

    2007-01-01

    The ten-years presidency of Alberto Fujimori in Peru is a classic example of the sort of hybrid democracy that emerged in various Latin American countries in the 1990s, combining a mixture of democratic and clearly non-democratic elements. Fujimori was one of the more autocratic Latin American leaders of the 1990s, he is being the only regime formally to break with pre-existing constitutional rules. Closely tied to the military and intelligence apparatus, his government involved a concentrati...

  3. Efficiency of Rectification: Reversible vs. Irreversible Regimes

    Science.gov (United States)

    Sokolov, I. M.

    2002-11-01

    Both man-made locomotive devices and molecular motors use gears to transform a reciprocating motion into a directed one. One of the most common gears is a rectifier, a mechanically irreversible appliance. The maximal energetic efficiency of an isothermic gear is bounded by unity, as a consequence of the Second Law. However, approaching this ideal efficiency does not imply approaching reversibility. We discuss what properties of a rectifier mostly influence the transduction efficiency and show that an appliance which locks under backward force is just the one which can approach the ideal efficiency either in the reversible or in the irreversible regime.

  4. The Tributary Regime in the oil sector

    International Nuclear Information System (INIS)

    The tributary regime of the oil sector, is framed by the fiscal crisis that the country, maxim if one keeps in mind the importance of the fiscal revenues originated in the exploitation of these resources in Colombia, so much for the tribute coming from the foreign investment of the sector, like for the utilities generated by ECOPETROL and its impact in the public finances. However in front of this focus, the strategic importance of maintaining the investment in hydrocarbons and the paper that the fiscal politics and the tributary politics for the sector should play in the future and they constitute the government's key pieces

  5. Random nanolasing in the Anderson localized regime

    DEFF Research Database (Denmark)

    Liu, Jin; Garcia, P. D.; Ek, Sara;

    2014-01-01

    multiple scattering. The applicability of random lasers has been limited due to multidirectional emission, lack of tunability, and strong mode competition with chaotic fluctuations due to a weak mode confinement. The regime of Anderson localization of light has been proposed for obtaining stable multimode...... random lasing, and initial work concerned macroscopic one-dimensional layered media. Here, we demonstrate on-chip random nanolasers where the cavity feedback is provided by the intrinsic disorder. The strong confinement achieved by Anderson localization reduces the spatial overlap between lasing modes...

  6. Asian Aspirations for Climate Regime Beyond 2012

    International Nuclear Information System (INIS)

    This report is based on the second round of 'The Asia-Pacific Consultations on Climate Regime Beyond 2012' in 2006 to further advance the frank exchange of opinions of policy makers, academics, and the private sector on specific issues of high priority to the region. These include: energy security and development, Clean Development Mechanism (CDM), technology development and transfer, and adaptation. This report presents a summary of what has been learnt through the current consultations, interviews, and questionnaire surveys with policy makers and climate policy researchers across the region

  7. Langmuir wave filamentation in the kinetic regime

    CERN Document Server

    Silantyev, Denis A; Rose, Harvey A

    2016-01-01

    Nonlinear Langmuir wave in the kinetic regime $k\\lambda_D\\gtrsim0.2$ has a transverse instability, where $k$ is the wavenumber and $\\lambda_D$ is the Debye length. The nonlinear stage of that instability development leads to the filamentation of Langmuir waves. Here we study the linear stage of transverse instability of both Bernstein-Greene-Kruskal (BGK) modes and dynamically prepared BGK-like initial conditions to find the same instability growth rate suggesting the universal mechanism for the kinetic saturation of stimulated Raman scatter in laser-plasma interaction experiments. Multidimensional Vlasov simulations results are compared to the theoretical predictions.

  8. Reconfigurable photoinduced metamaterials in the microwave regime

    CERN Document Server

    Rizza, Carlo; De Paulis, Francesco; Palange, Elia; Orlandi, Antonio; Columbo, Lorenzo; Prati, Franco

    2014-01-01

    We investigate optically reconfigurable dielectric metamaterials at gigahertz frequencies. More precisely, we study the microwave response of a subwavelength grating optically imprinted into a semiconductor slab. In the homogenized regime, we analytically evaluate the ordinary and extraordinary component of the effective permittivity tensor by taking into account the photo-carrier dynamics described by the ambipolar diffusion equation. We analyze the impact of semiconductor parameters on the gigahertz metamaterial response which turns out to be highly reconfigurable by varying the photogenerated grating and which can show a marked anisotropic behavior.

  9. The design of environmental regimes: Social construction, contextuality, and improvisation

    OpenAIRE

    Lejano

    2006-01-01

    While much of the literature on environmental regimes has focused on effectiveness, this article takes a new look at a lesser-studied topic, the evolution of regime design. Understanding how regimes differ in design, and how various factors and processes shape such design, is important if we are to more carefully craft these regimes. We should also pay close attention to the formative role of social construction and context. Focusing on transboundary marine programs, we see that their designs...

  10. Low-frequency regime transitions and predictability of regimes in a barotropic model

    CERN Document Server

    Nadiga, B T

    2016-01-01

    Predictability of flow is examined in a barotropic vorticity model that admits low frequency regime transitions between zonal and dipolar states. Such transitions in the model were first studied by Bouchet and Simonnet (2009) and are reminiscent of regime change phenomena in the weather and climate systems wherein extreme and abrupt qualitative changes occur, seemingly randomly, after long periods of apparent stability. Mechanisms underlying regime transitions in the model are not well understood yet. From the point of view of atmospheric and oceanic dynamics, a novel aspect of the model is the lack of any source of background gradient of potential-vorticity such as topography or planetary gradient of rotation rate (e.g., as in Charney & DeVore '79). We consider perturbations that are embedded onto the system's chaotic attractor under the full nonlinear dynamics as bred vectors---nonlinear generalizations of the leading (backward) Lyapunov vector. We find that ensemble predictions that use bred vector per...

  11. 氮肥施用量对豫东黄潮土区不同肥力土壤大蒜产量的影响%Effects of Nitrogen Fertilizer Application Amount on Garlic Yield in Different Fertility Soil in Yellow Fluvo-aquic Soil Region in Eastern Henan

    Institute of Scientific and Technical Information of China (English)

    刘艳侠; 闫挺起; 皇甫自起; 鲁启安; 靳秀丽

    2015-01-01

    The effect of nitrogen application amount on garlic yield under different soil fertility levels was studied with Songcheng garlic as material in yellow fluvo-aquic soil region in eastern Henan. The results showed that when the application amount of the phosphorus and potassium fertilizer were suitable,the re-lationship between garlic yield and application amount of nitrogen fertilizer under all the soil fertility levels was fit for quadratic function. The optimal application amounts of fertilizer were phosphorus ( P2 O5 ) of 180. 0 kg/ha,potassium(K2O) of 300. 0 kg/ha,nitrogen(N) of 354. 0 kg/ha for high yield field, phos-phorus(P2O5) of 135. 0 kg/ha,potassium(K2O) of 240. 0 kg/ha,nitrogen(N) of 288. 0 kg/ha for medi-um yield filed,and phosphorus(P2O5) of 90. 0 kg/ha,potassium(K2O) of 180. 0 kg/ha,nitrogen(N) of 264. 0 kg/ha for low yield filed,the corresponding best economic outputs were 22 209. 0 kg/ha,17 041. 5 kg/ha and 12 511. 5 kg/ha,respectively.%以头薹兼用型品种宋城大蒜为供试材料,研究了氮肥施用量对豫东黄潮土区不同肥力土壤大蒜产量的影响。结果表明:在磷、钾肥适宜水平下,高、中、低产田氮肥施用量与蒜头产量均呈二次曲线函数关系。高产田在施磷(P2O5)180.0 kg/hm2、钾(K2O)300.0 kg/hm2的条件下,最佳施氮量354.0 kg/hm2,最佳经济产量为22209.0 kg/hm2;中产田在施磷(P2O5)135.0 kg/hm2、钾(K2O)240.0 kg/hm2的条件下,最佳施氮量288.0 kg/hm2,最佳经济产量为17041.5 kg/hm2;低产田在施磷(P2O5)90.0 kg/hm2、钾(K2O)180.0 kg/hm2的条件下,最佳施氮量264.0 kg/hm2,最佳经济产量为12511.5 kg/hm2。

  12. Hard and Soft Excitation Regimes of Kerr Frequency Combs

    CERN Document Server

    Matsko, Andrey B; Ilchenko, Vladimir S; Seidel, David; Maleki, Lute

    2011-01-01

    We theoretically study the stability conditions and excitation regimes of hyper-parametric oscillation and Kerr frequency comb generation in continuously pumped nonlinear optical resonators possessing anomalous group velocity dispersion. We show that both hard and soft excitation regimes are possible in the resonators. Selection between the regimes is achieved via change in the parameters of the pumping light.

  13. Level-ARCH Short Rate Models with Regime Switching

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    This paper introduces regime switching volatility into level- ARCH models for the short rates of the US, the UK, and Germany. Once regime switching and level effects are included there are no gains from including ARCH effects. It is of secondary importance exactly how the regime switching...

  14. Change of secondary water regime of Paks NPP. Change of secondary water regime at Unit 2

    International Nuclear Information System (INIS)

    The installation of high pH water regime during the 17th cycle of Unit 2 aimed to decrease the amount of transportation inlet of erosion-corrosion products (magnitude) in feedwater to SGs. The resolution of OAH-NBI permitting the installation ordained to make an evaluation of the process. The main conclusions and results are discussed. The high pH water regime proved to be adequate in the case of Unit 2 as well, similarly to Units 3, 4 and 1. (R.P.)

  15. The Asymptotic Regime of High Density QCD

    CERN Document Server

    Gay-Ducati, M B

    2000-01-01

    We discuss the distinct approaches for high density QCD (hdQCD) in the asymptotic regime of large values of parton density. We derive the AGL equation for running coupling constant and obtain the asymptotic solution, demonstrating that the property of partial saturation of the solution of the AGL equation is not modified by the running of the coupling constant. We show that in this kinematical regime, the solution of the AGL equation coincides with the solution of an evolution equation, obtained recently using the McLerran-Venugopalan approach. Using the asymptotic behavior of the gluon distribution we calculate the $F_2$ structure function assuming first that the leading twist relation between these two quantities is valid and second that this relation is modified by the higher twist terms associated to the unitarity corrections. In the first case we obtain that the corresponding $F_2$ structure function is linearly proportional to $ln s$, which agrees with the results obtained recently by Kovchegov using a ...

  16. Dynamic regimes of random fuzzy logic networks

    Science.gov (United States)

    Wittmann, Dominik M.; Theis, Fabian J.

    2011-01-01

    Random multistate networks, generalizations of the Boolean Kauffman networks, are generic models for complex systems of interacting agents. Depending on their mean connectivity, these networks exhibit ordered as well as chaotic behavior with a critical boundary separating both regimes. Typically, the nodes of these networks are assigned single discrete states. Here, we describe nodes by fuzzy numbers, i.e. vectors of degree-of-membership (DOM) functions specifying the degree to which the nodes are in each of their discrete states. This allows our models to deal with imprecision and uncertainties. Compatible update rules are constructed by expressing the update rules of the multistate network in terms of Boolean operators and generalizing them to fuzzy logic (FL) operators. The standard choice for these generalizations is the Gödel FL, where AND and OR are replaced by the minimum and maximum of two DOMs, respectively. In mean-field approximations we are able to analytically describe the percolation and asymptotic distribution of DOMs in random Gödel FL networks. This allows us to characterize the different dynamic regimes of random multistate networks in terms of FL. In a low-dimensional example, we provide explicit computations and validate our mean-field results by showing that they agree well with network simulations.

  17. Variety of synchronous regimes in neuronal ensembles

    Science.gov (United States)

    Komarov, M. A.; Osipov, G. V.; Suykens, J. A. K.

    2008-09-01

    We consider a Hodgkin-Huxley-type model of oscillatory activity in neurons of the snail Helix pomatia. This model has a distinctive feature: It demonstrates multistability in oscillatory and silent modes that is typical for the thalamocortical neurons. A single neuron cell can demonstrate a variety of oscillatory activity: Regular and chaotic spiking and bursting behavior. We study collective phenomena in small and large arrays of nonidentical cells coupled by models of electrical and chemical synapses. Two single elements coupled by electrical coupling show different types of synchronous behavior, in particular in-phase and antiphase synchronous regimes. In an ensemble of three inhibitory synaptically coupled elements, the phenomenon of sequential synchronous dynamics is observed. We study the synchronization phenomena in the chain of nonidentical neurons at different oscillatory behavior coupled with electrical and chemical synapses. Various regimes of phase synchronization are observed: (i) Synchronous regular and chaotic spiking; (ii) synchronous regular and chaotic bursting; and (iii) synchronous regular and chaotic bursting with different numbers of spikes inside the bursts. We detect and study the effect of collective synchronous burst generation due to the cluster formation and the oscillatory death.

  18. Regimes of piezoelectric transformer operation II

    International Nuclear Information System (INIS)

    Piezoelectric transformers (PTs) have some attractive features for using them in power supply systems such as high efficiency and high power density, a high level of isolation between primary and secondary sides, a flat design which is well suited for a lot of applications and a low level of electromagnetic noise, just to name a few. For any application it is of utmost importance to know the behavior of a piezoelectric transformer under different conditions, which we call regimes of transformer operation. Based on this knowledge, criteria for safe operation of the PT in the power supply system and hence for the whole system as well can be derived. After having introduced the regimes of piezoelectric transformer operation in a first article on this topic in 2006 [1], in this paper we will present the derivation of important parameters based on measurements by way of an example of a symmetric PT. These measurements facilitate the basic understanding for choosing the appropriate transformer parameters necessary for its optimal as well as safe and controlled operation in power supply systems

  19. Characterizing multistationarity regimes in biochemical reaction networks.

    Directory of Open Access Journals (Sweden)

    Irene Otero-Muras

    Full Text Available Switch like responses appear as common strategies in the regulation of cellular systems. Here we present a method to characterize bistable regimes in biochemical reaction networks that can be of use to both direct and reverse engineering of biological switches. In the design of a synthetic biological switch, it is important to study the capability for bistability of the underlying biochemical network structure. Chemical Reaction Network Theory (CRNT may help at this level to decide whether a given network has the capacity for multiple positive equilibria, based on their structural properties. However, in order to build a working switch, we also need to ensure that the bistability property is robust, by studying the conditions leading to the existence of two different steady states. In the reverse engineering of biological switches, knowledge collected about the bistable regimes of the underlying potential model structures can contribute at the model identification stage to a drastic reduction of the feasible region in the parameter space of search. In this work, we make use and extend previous results of the CRNT, aiming not only to discriminate whether a biochemical reaction network can exhibit multiple steady states, but also to determine the regions within the whole space of parameters capable of producing multistationarity. To that purpose we present and justify a condition on the parameters of biochemical networks for the appearance of multistationarity, and propose an efficient and reliable computational method to check its satisfaction through the parameter space.

  20. Elastic regimes of subisostatic athermal fiber networks.

    Science.gov (United States)

    Licup, A J; Sharma, A; MacKintosh, F C

    2016-01-01

    Athermal models of disordered fibrous networks are highly useful for studying the mechanics of elastic networks composed of stiff biopolymers. The underlying network architecture is a key aspect that can affect the elastic properties of these systems, which include rich linear and nonlinear elasticity. Existing computational approaches have focused on both lattice-based and off-lattice networks obtained from the random placement of rods. It is not obvious, a priori, whether the two architectures have fundamentally similar or different mechanics. If they are different, it is not clear which of these represents a better model for biological networks. Here, we show that both approaches are essentially equivalent for the same network connectivity, provided the networks are subisostatic with respect to central force interactions. Moreover, for a given subisostatic connectivity, we even find that lattice-based networks in both two and three dimensions exhibit nearly identical nonlinear elastic response. We provide a description of the linear mechanics for both architectures in terms of a scaling function. We also show that the nonlinear regime is dominated by fiber bending and that stiffening originates from the stabilization of subisostatic networks by stress. We propose a generalized relation for this regime in terms of the self-generated normal stresses that develop under deformation. Different network architectures have different susceptibilities to the normal stress but essentially exhibit the same nonlinear mechanics. Such a stiffening mechanism has been shown to successfully capture the nonlinear mechanics of collagen networks. PMID:26871101

  1. Essence and Prospect of International Export Control Regimes

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ International export control regimes are referring to the regimes and systems concerning limitation of export and transference of military-use and dual-use items and related parts as well as technologies. In the past couple of years, the control regimes have shown a strengthening posture. In addition, a new global export control regime is brewing. Hence export control has caught the attention of the international community, and particularly of the circles of armament control and commerce. The author would like to make some analyses of the posture and then try to predict the trend of international export control regimes.

  2. Quaternary Faults and Stress Regime of Venezuela

    Directory of Open Access Journals (Sweden)

    F.A. Audemard M.

    2006-12-01

    Full Text Available Spatial configuration of Quaternary active tectonic features along the southern Caribbean plate boundary suggests that the region is subject to a compressive strike-slip (transpressional senso lato regime, characterized by a NNW-SSE maximum horizontal stress (sH=s1 and/or an ENE-WSW minimum (s h=s3 or s2 horizontal stress. Stress inversion applied to fault-plane kinematic indicators measured essentially in Plio-Quaternary sedimentary rocks confirms this tectonic regime. Accordingly, this stress regime is responsible for the Quaternary activity and kinematics of six sets of brittle features along northern Venezuela (from Colombia in the west to Trinidad in the east: (1 east-west rightlateral faults, (2 NW right-lateral faults -acting as synthetic Riedel shears-, (3 ENE to east-west dextral faults -P shears-, (4 NNW normal faults, (5 almost north-south left-lateral faults -antithetic Riedel shears- and (6 mostly subsurface ENE reverse faults associated with folding of the same orientation. Brittle deformation conforms to the simple shear model, although not all the deformation can be accounted for it since strain partitioning is also taking place because regional folding and thrusting are due to the normal-to-structure component of the relative slip vector between the Caribbean and South America plates. On the other hand, the maximum horizontal stress in western Venezuela, particularly in the Maracaibo block and south of the Oca-Ancón fault, progressively turns counter-clockwise to become more east-west oriented, producing left- and right-lateral slip along the north-south striking and NE-SW striking faults, respectively. The orientation and spatial variation of this regional stress field in western Venezuela results from the superposition of the two major neighboring interplate maximum horizontal stress orientations (sH: roughly east-west trending stress across the Nazca-South America type-B subduction along the pacific coast of Colombia and NNW

  3. Institutional design and regime effectiveness in transboundary river management – the Elbe water quality regime

    Directory of Open Access Journals (Sweden)

    I. Dombrowsky

    2007-06-01

    Full Text Available The literature on transboundary river management suggests that institutions play an important role in bringing cooperation about. However, the knowledge on how they should be designed in order to do so remains limited. One way to learn more about adequate institutional design is to assess the effectiveness of existing regimes, and to trace the causal relationships leading to the respective outcomes. In order to gain further insights into the relationship of institutional design and regime effectiveness, this paper presents a study on the water quality regime of the International Commission for the Protection of the Elbe (ICPE. The analysis is based on a review of pertinent documents and ten qualitative interviews with Czech and German Commission members and NGO representatives. Particular emphasis has been put on determining the ICPE's specific contribution and the no-regime counterfactual as well as on the perceived expedience of the institutional arrangements. The study shows that overall due to external as well as internal institutional factors the ICPE proved relatively successful, and as such it also provides insights into how institutions matter: The commission served as platform for joint problem solving by identifying priorities for action. These international obligations increased the power of national administrations and their access to funds. At the same time, the Commission's reporting to the public served as an enforcement mechanism. However, the ICPE's contribution towards achieving the various goals varied significantly between the different areas of activity. It was high where the main responsibility for action was with the public authorities, such as in the area of wastewater treatment and the establishment of an international alarm plan and model. It was practically non existent in the reduction of non-point pollution from agriculture, where the success depended on the behavior of individual private actors (farmers. From a

  4. Two regimes of forced turbulent convection

    CERN Document Server

    Eidelman, A; Kleeorin, N; Rogachevskii, I; Sapir-Katiraie, I

    2009-01-01

    We study experimentally a forced turbulent convection in the Rayleigh-B\\'{e}nard apparatus with an additional source of turbulence produced by the two oscillating grids located nearby the side walls of the chamber. Two different regimes have been observed in the forced turbulent convection. When the frequency of the grid oscillations f>2 Hz, the large-scale circulation (LSC) is totally destroyed, and the destruction of the LSC is accompanied by a strong change of the mean temperature distribution. For the very low frequency the thermal structure inside the LSC is inhomogeneous and anisotropic. The hot thermal plumes accumulate at one side of LSC, and cold plumes concentrate at the opposite side of LSC. The mean temperature gradient in the horizontal direction inside the LSC is significantly larger than in the vertical direction. For the high frequency (f > 10 Hz), LSC has not been observed and the mean temperature gradient in the central flow region in the vertical direction, \

  5. The Great Lakes' regional climate regimes

    Science.gov (United States)

    Sugiyama, Noriyuki

    For the last couple of decades, the Great Lakes have undergone rapid surface warming. In particular, the magnitude of the summer surface-warming trends of the Great Lakes have been much greater than those of surrounding land (Austin and Colman, 2007). Among the Great Lakes, the deepest Lake Superior exhibited the strongest warming trend in its annual, as well as summer surface water temperature. We find that many aspects of this behavior can be explained in terms of the tendency of deep lakes to exhibit multiple regimes characterized, under the same seasonally varying forcing, by the warmer and colder seasonal cycles exhibiting different amounts of wintertime lake-ice cover and corresponding changes in the summertime lake-surface temperatures. In this thesis, we address the problem of the Great Lakes' warming using one-dimensional lake modeling to interpret diverse observations of the recent lake behavior. (Abstract shortened by ProQuest.).

  6. Regime shifts in models of dryland vegetation

    CERN Document Server

    Zelnik, Yuval R; Yizhaq, Hezi; Bel, Golan; Meron, Ehud

    2013-01-01

    Drylands are pattern-forming systems showing self-organized vegetation patchiness, multiplicity of stable states and fronts separating domains of alternative stable states. Pattern dynamics, induced by droughts or disturbances, can result in desertification shifts from patterned vegetation to bare soil. Pattern-formation theory suggests various scenarios for such dynamics; an abrupt global shift involving a fast collapse to bare soil, a gradual global shift involving the expansion and coalescence of bare-soil domains, and an incipient shift to a hybrid state consisting of stationary bare-soil domains in an otherwise periodic pattern. Using models of dryland vegetation we address the question which of these scenarios can be realized. We found that the models can be split into two groups: models that exhibit multiplicity of periodic-pattern and bare-soil states, and models that exhibit, in addition, multiplicity of hybrid states. Furthermore, in all models we could not identify parameter regimes in which bare-s...

  7. Environment Flow Assessment with Flow Regime Transition

    Science.gov (United States)

    Su, J.; Ho, C. C.; Chang, L. C.

    2015-12-01

    To avoid worsen river and estuarine ecosystems cause by overusing water resources, environmental flows conservation is applied to reduce the impact of river environment. Environmental flows refer to water provided within a river, wetland or coastal zone to sustain ecosystems and benefits to human wellbeing. Environment flow assessment is now widely accepted that a naturally variable flow regime, rather than just a minimum low flow. In this study, we propose four methods, experience method, Tenant method, hydraulic method and habitat method to assess the environmental flow of base flow, flush flow and overbank flow with different discharge, frequency and occurrence period. Dahan River has been chosen as a case to demonstrate the assessment mechanism. The alternatives impact analysis of environment and human water used provides a reference for stakeholders when holding an environmental flow consultative meeting.

  8. Nonlinear regimes of forced magnetic reconnection

    Energy Technology Data Exchange (ETDEWEB)

    Vekstein, G., E-mail: g.vekstein@manchester.ac.uk [JBCA, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); STEL, Nagoya University, Nagoya, Aichi 464-8601 (Japan); Kusano, K. [STEL, Nagoya University, Nagoya, Aichi 464-8601 (Japan)

    2015-09-15

    This letter presents a self-consistent description of nonlinear forced magnetic reconnection in Taylor's model of this process. If external boundary perturbation is strong enough, nonlinearity in the current sheet evolution becomes important before resistive effects come into play. This terminates the current sheet shrinking that takes place at the linear stage and brings about its nonlinear equilibrium with a finite thickness. Then, in theory, this equilibrium is destroyed by a finite plasma resistivity during the skin-time, and further reconnection proceeds in the Rutherford regime. However, realization of such a scenario is unlikely because of the plasmoid instability, which is fast enough to develop before the transition to the Rutherford phase occurs. The suggested analytical theory is entirely different from all previous studies and provides proper interpretation of the presently available numerical simulations of nonlinear forced magnetic reconnection.

  9. Different spreading regimes of spray-flames

    Science.gov (United States)

    Suard, Sylvain; Haldenwang, Pierre; Nicoli, Colette

    2004-05-01

    We present a minimal model of spray combustion to investigate a flame front propagating through a fuel-lean mixture of fuel vapor, droplets and air. The model relies on a main control parameter, Da, named the Damkoehler number, which allows us to take into account a large variety of fuel sprays. Numerical results reveal, as a function of Da, a wide range of spray-flame structures, including the classical gaseous premixed flame, a specific regime controlled by vaporisation, and a pulsating mode of propagation. The latter appears when the vaporisation is smaller than (or equal to) the reaction time, and it occurs even with a unit Lewis number. To cite this article: S. Suard et al., C. R. Mecanique 332 (2004).

  10. The role of the media in establishing international security regimes

    Directory of Open Access Journals (Sweden)

    Chanan Naveh

    2005-04-01

    Full Text Available This article focuses primarily on the media's impact on international security regimes. It explores the ways in which the media affect the lifecycles of international regimes, from the time they are first conceived of, through their establishment, consolidation and stabilization, up until their ultimate demise. Although this paper highlights the media's role in the evolution of security regimes, it is clear that, regardless of the regime in question, media play a role throughout the lifecycle of all international regimes, whatever their character. In order to analyze the relationships of the media with security regimes in general, and specifically their contribution to each stage in their development, the article utilizes methodologies from the field of communication studies. It examines the media's agenda, "news values" and various functions, and their ability to mobilize public support for the particular issue of the regime. To date, most studies have explored the interaction between media communication patterns and global developments at the state level, or in relation to the formulation of foreign policy, while largely ignoring the international dimension of the relationship. This article attempts to remedy this situation, and the relevant processes are analysed in a case study of the anti-Iraq international security regime. It should be noted that although the paper focuses on the specific anti-Iraqi regime, it is part of a more general Anti-Rogue actors regime which includes the war against global terrorism. The study of the development of the anti-Iraq press-security regime teaches us that during international crises the media mobilize and unanimously support the regime fighting the "bad guys." But, when the regime develops and enters disputed turfs and begins to lose its legitimacy, media support diminishes, and the media may even develop into an opposing force and may join the actors fighting against this regime. Moreover, the study of

  11. Fiscal Policy and Welfare under Different Exchange Rate Regimes

    DEFF Research Database (Denmark)

    Østrup, Finn

    , and secondbecause the government's inclination to expand government spending is affectedby inflation which depends on the exchange rate regime. At low rates of inflation,the government is inclined to set a higher level of government spending under afixed exchange rate regime than under a floating exchange rate...... regime in whichthe monetary authority optimises preferences which include an employment targetand an inflation target. As government spending affects the representativeindividual's utility, the choice of exchange rate regime has an impact on welfare.Keywords: exchange rate regimes; fiscal policy......The article analyses how government spending is determined under differentexchange rate regimes in the context of a small open economy. Assumingnominal wage contracts which last for one period and assuming a benevolentgovernment which determines government spending to optimise...

  12. Detection and Assessment of Ecosystem Regime Shifts from Fisher Information

    OpenAIRE

    B. Roy Frieden; Christopher W. Pawlowski; Heriberto Cabezas; Arunprakash T. Karunanithi

    2008-01-01

    Ecosystem regime shifts, which are long-term system reorganizations, have profound implications for sustainability. There is a great need for indicators of regime shifts, particularly methods that are applicable to data from real systems. We have developed a form of Fisher information that measures dynamic order in complex systems. Here we propose the use of Fisher information as a means of: (1) detecting dynamic regime shifts in ecosystems, and (2) assessing the quality of the shift in terms...

  13. Spacetime-noncommutativity regime of Loop Quantum Gravity

    OpenAIRE

    AMELINO-CAMELIA, Giovanni; da Silva, Malú Maira; Ronco, Michele; Cesarini, Lorenzo; Lecian, Orchidea Maria

    2016-01-01

    A recent study by Bojowald and Paily provided a path toward the identification of an effective quantum-spacetime picture of Loop Quantum Gravity, applicable in the "Minkowski regime", the regime where the large-scale (coarse-grained) spacetime metric is flat. A pivotal role in the analysis is played by Loop-Quantum-Gravity-based modifications to the hypersurface deformation algebra, which leave a trace in the Minkowski regime. We here show that the symmetry-algebra results reported by Bojowal...

  14. Apparel exportism in Kenya: international regimes, chain governance and upgrading

    OpenAIRE

    Kindiki, M. M.

    2011-01-01

    An important question in development is how far can the contemporary global context create industrial development opportunities for the South, particularly for Low Income Countries? In an important sense, this can only be answered in non-abstract terms, since the institutional conditions facing particular industries at particular times are highly specific. In this research, a configuration of four regimes- the structural regime on production and trade in apparel, the labour regime, the neo-st...

  15. Flow regimes in a trapped vortex cell

    Science.gov (United States)

    Lasagna, D.; Iuso, G.

    2016-03-01

    This paper presents results of an experimental investigation on the flow in a trapped vortex cell, embedded into a flat plate, and interacting with a zero-pressure-gradient boundary layer. The objective of the work is to describe the flow features and elucidate some of the governing physical mechanisms, in the light of recent investigations on flow separation control using vortex cells. Hot-wire velocity measurements of the shear layer bounding the cell and of the boundary layers upstream and downstream are reported, together with spectral and correlation analyses of wall-pressure fluctuation measurements. Smoke flow visualisations provide qualitative insight into some relevant features of the internal flow, namely a large-scale flow unsteadiness and possible mechanisms driving the rotation of the vortex core. Results are presented for two very different regimes: a low-Reynolds-number case where the incoming boundary layer is laminar and its momentum thickness is small compared to the cell opening, and a moderately high-Reynolds-number case, where the incoming boundary layer is turbulent and the ratio between the momentum thickness and the opening length is significantly larger than in the first case. Implications of the present findings to flow control applications of trapped vortex cells are also discussed.

  16. Scaling regimes in spherical shell rotating convection

    CERN Document Server

    Gastine, T; Aubert, J

    2016-01-01

    Rayleigh-B\\'enard convection in rotating spherical shells can be considered as a simplified analogue of many astrophysical and geophysical fluid flows. Here, we use three-dimensional direct numerical simulations to study this physical process. We construct a dataset of more than 200 numerical models that cover a broad parameter range with Ekman numbers spanning $3\\times 10^{-7} \\leq E \\leq 10^{-1}$, Rayleigh numbers within the range $10^3 < Ra < 2\\times 10^{10}$ and a Prandtl number unity. We investigate the scaling behaviours of both local (length scales, boundary layers) and global (Nusselt and Reynolds numbers) properties across various physical regimes from onset of rotating convection to weakly-rotating convection. Close to critical, the convective flow is dominated by a triple force balance between viscosity, Coriolis force and buoyancy. For larger supercriticalities, a subset of our numerical data approaches the asymptotic diffusivity-free scaling of rotating convection $Nu\\sim Ra^{3/2}E^{2}$ in ...

  17. Multimode optomechanical system in the quantum regime

    CERN Document Server

    Nielsen, William H P; Møller, Christoffer B; Polzik, Eugene S; Schliesser, Albert

    2016-01-01

    We realise a simple and robust optomechanical system with a multitude of long-lived ($Q>10^7$) mechanical modes in a phononic-bandgap shielded membrane resonator. An optical mode of a compact Fabry-Perot resonator detects these modes' motion with a measurement rate ($96~\\mathrm{kHz}$) that exceeds the mechanical decoherence rates already at moderate cryogenic temperatures ($10\\,\\mathrm{K}$). Reaching this quantum regime entails, i.~a., quantum measurement backaction exceeding thermal forces, and thus detectable optomechanical quantum correlations. In particular, we observe ponderomotive squeezing of the output light mediated by a multitude of mechanical resonator modes, with quantum noise suppression up to -2.4 dB (-3.6 dB if corrected for detection losses) and bandwidths $\\lesssim 90\\,\\mathrm{ kHz}$. The multi-mode nature of the employed membrane and Fabry-Perot resonators lends itself to hybrid entanglement schemes involving multiple electromagnetic, mechanical, and spin degrees of freedom.

  18. Global fishery prospects under contrasting management regimes.

    Science.gov (United States)

    Costello, Christopher; Ovando, Daniel; Clavelle, Tyler; Strauss, C Kent; Hilborn, Ray; Melnychuk, Michael C; Branch, Trevor A; Gaines, Steven D; Szuwalski, Cody S; Cabral, Reniel B; Rader, Douglas N; Leland, Amanda

    2016-05-01

    Data from 4,713 fisheries worldwide, representing 78% of global reported fish catch, are analyzed to estimate the status, trends, and benefits of alternative approaches to recovering depleted fisheries. For each fishery, we estimate current biological status and forecast the impacts of contrasting management regimes on catch, profit, and biomass of fish in the sea. We estimate unique recovery targets and trajectories for each fishery, calculate the year-by-year effects of alternative recovery approaches, and model how alternative institutional reforms affect recovery outcomes. Current status is highly heterogeneous-the median fishery is in poor health (overfished, with further overfishing occurring), although 32% of fisheries are in good biological, although not necessarily economic, condition. Our business-as-usual scenario projects further divergence and continued collapse for many of the world's fisheries. Applying sound management reforms to global fisheries in our dataset could generate annual increases exceeding 16 million metric tons (MMT) in catch, $53 billion in profit, and 619 MMT in biomass relative to business as usual. We also find that, with appropriate reforms, recovery can happen quickly, with the median fishery taking under 10 y to reach recovery targets. Our results show that commonsense reforms to fishery management would dramatically improve overall fish abundance while increasing food security and profits. PMID:27035953

  19. Crossing into the substellar regime in Praesepe

    CERN Document Server

    Chappelle, R J; Steele, I A; Dobbie, P D; Magazzù, A

    2005-01-01

    We present the results of a deep optical 2.6 square degree survey with near infrared follow-up measurements of the intermediate-aged Praesepe open cluster. The survey is complete to I=21.3, Z=20.5, corresponding to ~0.06 Solar Masses assuming a cluster age of 0.5 Gyrs. Using 3-5 pass-bands to constrain cluster membership, we identify 32 new low mass cluster members, at least 4 of which are likely to be substellar. We use the low mass census to trace the region where the sequence moves away from the NEXTGEN towards the Dusty regime at Teff = 2200K. In doing so, we identify four unresolved binaries, yielding a substellar binary fraction of ~30 percent. The binary fractions appear to decrease below 0.1 Solar Masses, in contrast to the rising fractions found in the Pleiades. We also identify a paucity of late M dwarfs, thought to be due to a steepening in the mass-luminosity relation at these spectral types, and compare the properties of this gap in the sequence to those observed in younger clusters. We note an o...

  20. On the ontological emergence from quantum regime

    Energy Technology Data Exchange (ETDEWEB)

    Luty, Damian [Adam Mickiewicz University, Poznan (Poland)

    2014-07-01

    There are several views on the relation between quantum physics and theory of relativity (especially General Relativity, GR). A popular perspective is this: GR with its macroscopic gravitational effects will turn out to be a limit of a more fundamental theory which should consider discrete physics and not deal with continuity (like theory of relativity). Thus, GR will emerge from a more basic theory, which should be quantum-like. One could call this an epistemic emergence view towards fundamental theories. The question is, given that scientific realism is valid: should emergence be a fundamental notion in our ontological view about the evolving, physical Universe? Is there an ontological emergence fully compatible with the notion of fundamentality? I argue that if we want to defend ontological emergence (from quantum to macroscopic regime) as something fundamental, we will arrive at the position of metaphysics of dispositions (and I argue, why this is undesirable), or conclude, that we cannot square fully fundamental ontology with the notion of emergence, and that we have to accept an ontological pluralism relativised to a certain scale. I defend the latter proposition, showing, that epistemic emergence doesn't entail (logically) ontological emergence.

  1. Regime shifts in a social-ecological system

    OpenAIRE

    Lade, Steven J.; Tavoni, Alessandro; Levin, Simon A.; Schlüter, Maja

    2013-01-01

    Ecological regime shifts are rarely purely ecological. Not only is the regime shift frequently triggered by human activity, but the responses of relevant actors to ecological dynamics are often crucial to the development and even existence of the regime shift. Here, we show that the dynamics of human behaviour in response to ecological changes can be crucial in determining the overall dynamics of the system. We find a social-ecological regime shift in a model of harvesters of a common-pool re...

  2. Institutional design and regime effectiveness in transboundary river management – the Elbe water quality regime

    Directory of Open Access Journals (Sweden)

    I. Dombrowsky

    2008-02-01

    Full Text Available The literature on transboundary river management suggests that institutions play an important role in bringing about cooperation. However, knowledge about how such institutions should be designed in order to do so remains limited. One way to learn more about adequate institutional design is to assess the effectiveness of existing regimes, and to trace the causal relationships that lead to the respective outcomes. In order to gain further insights into the relationship between institutional design and regime effectiveness, this paper presents a study on the water quality regime of the International Commission for the Protection of the Elbe (ICPE. The analysis is based on a review of pertinent documents and ten qualitative interviews with Czech and German Commission members and NGO representatives. Particular emphasis has been put on determining the ICPE's specific contribution and the no-regime counterfactual as well as on the perceived expediency of the institutional arrangements. The study shows overall that the countries were relatively successful in improving water quality in the Elbe basin. However, this outcome can only partly be attributed to the ICPE itself. Furthermore, the ICPE's contribution towards achieving the various goals varied significantly between the different areas of activity: it was relatively significant where the main responsibility for action lay with the public authorities, such as in the area of wastewater treatment and the establishment of an international alarm plan and model, but was practically non-existent in the reduction of non-point pollution from agriculture, where success depended on the behavior of individual private actors (farmers. The commission contributed towards problem solving by serving as a forum for the joint identification of priorities for action from a basin-wide perspective. The resulting international obligations increased the power of national water administrations and their access to funds

  3. Varieties of Economic Growth Regimes, Types of Macroeconomic Policies, and Policy Regime: A Post-Keynesian Analysis

    OpenAIRE

    Hiroshi Nishi

    2012-01-01

    This study explores the effects of macroeconomic policies on measures of macroeconomic performance such as growth and inflation by setting up a dynamic post-Keynesian model with government and central bank interventions. In doing so, this study reconsiders the arguments in favor of a policy regime. The model in this paper generates several varieties of economic growth regimes and inflation dynamics. The economic growth regimes are defined by the relationship between economic growth, the incom...

  4. 长期平衡施肥对潮土微生物活性和玉米养分吸收的影响%EFFECTS OF LONG-TERM BALANCED FERTILIZATION ON MICROBIAL ACTIVITY AND NUTRIENT UPTAKE OF MAIZE IN A FLUVO-AQUIC SOIL

    Institute of Scientific and Technical Information of China (English)

    王俊华; 胡君利; 林先贵; 戴珏; 王军涛; 崔向超; 钦绳武

    2011-01-01

    利用中国科学院封丘农业生态实验站农田生态系统养分平衡长期定位试验地,研究氮磷钾平衡施肥(NPK)与缺素施肥(NK、PK、NP)对土壤微生物生物量、酶活性、呼吸强度以及玉米养分吸收的影响.结果发现,与不施肥对照(CK)相比,NPK处理玉米根系与茎叶生物量、籽粒产量以及植株氮磷钾吸收量均大幅提高,NP处理次之,PK与NK处理则无显著影响;同一处理玉米茎叶与根系养分含量接近,而籽粒的全氮和全磷含量较高、全钾含量偏低;与NPK处理相比,缺施氮、磷或钾肥均直接导致玉米植株相应养分的明显亏缺或其他养分的过量富集,但在根系、茎叶和籽粒部位的累积情况存在一定差异.与CK相比,所有施加磷肥的处理( NPK、NP、PK)土壤微生物生物量(碳、氮、磷)、脱氢酶、转化酶、脲酶与碱性磷酸酶活性以及土壤微生物代谢活性和土壤基础呼吸强度均显著升高(p<0.05),土壤微生物代谢熵则显著下降(p<0.05),而缺施磷肥的NK处理除显著提高脲酶活性外(p<0.05),对其他指标均无显著影响.结果表明,氮磷钾平衡施肥在促进土壤微生物繁育和保育微生物代谢活性以及促进作物生长和保证养分吸收等方面显得非常重要,而缺素施肥中以缺施磷肥的不利影响最为突出.%A long-term stationary field experiment on nutrient balance for farming ecosystem in the Fengqiu National Agro-ecological Experiment Station was made use of to investigate effects of balanced or unbalanced, fertilization on micro-bial biomass, enzymatic activities, and soil basal respiration as well as nutrient uptake of maize plants in a fluvo-aquic soil. The experiment was designed to have five treatments: fertilizer NPK, NP, PK, NK, and CK (without fertilization). The root biomass, straw biomass, grain yield, and total uptakes of N, P, K of maize plants were all greatly increased in Treatment NPK, and were also

  5. CSDP: Seismology of continental thermal regime

    Energy Technology Data Exchange (ETDEWEB)

    Aki, K.

    1989-04-01

    This is a progress report for the past one year of research (year 2 of 5-year project) under the project titled CSDP: Seismology of Continental Thermal Regime'', in which we proposed to develop seismological interpretation theory and methods applicable to complex structures encountered in continental geothermal areas and apply them to several candidate sites for the Continental Scientific Drilling Project. During the past year, two Ph.D. thesis works were completed under the present project. One is a USC thesis on seismic wave propagation in anisotropic media with application to defining fractures in the earth. The other is a MIT thesis on seismic Q and velocity structure for the magma-hydrothermal system of the Valles Caldera, New Mexico. The P.I. co-organized the first International Workshop on Volcanic Seismology at Capri, Italy in October 1988, and presented the keynote paper on the state-of-art of volcanic seismology''. We presented another paper at the workshop on Assorted Seismic Signals from Kilauea Volcano, Hawaii. Another international meeting, namely, the Chapman Conference on seismic anisotropy in the earth's crust at Berkeley, California in May 1988, was co-organized by the co-P.I. (P.C.L), and we presented our work on seismic waves in heterogeneous and anisotropic media. Adding the publications and presentations made in the past year to the list for the preceding year, the following table lists 21 papers published, submitted or presented in the past two years of the present project. 65 refs., 334 figs., 1 tab.

  6. Dissipation regimes for short wind waves

    Science.gov (United States)

    Caulliez, Guillemette

    2013-02-01

    The dissipation processes affecting short wind waves of centimeter and decimeter scales are investigated experimentally in laboratory. The processes include damping due to molecular viscosity, generation of capillary waves, microbreaking, and breaking. The observations were made in a large wind wave tank for a wide range of fetches and winds, using a laser sheet and a high-resolution video camera. The work aims at constructing a comprehensive picture of dissipative processes in the short wind wave field, to find for which scales particular dissipative mechanism may become important. Four distinct regimes have been identified. For capillary-gravity wave fields, i.e., for dominant waves with scales below 4 cm, viscous damping is found to be the main dissipation mechanism. The gravity-capillary wave fields with dominant wavelength less than 10 cm usually exhibit a train of capillary ripples at the crest wavefront, but no wave breaking. For such waves, the main dissipation process is molecular viscosity occurring through nonlinear energy cascade toward high-frequency motions. Microscale breaking takes place for waves longer than 10 cm and manifests itself in a very localized surface disruption on the forward face of the crest. Such events generate turbulent motions in water and thus enhance wave dissipation. Plunging breaking, characterized by formation of a crest bulge, a microjet hitting the water surface and a splash-up, occurs for short gravity waves of wavelength exceeding 20 cm. Macroscale spilling breaking is also observed for longer waves at high winds. In both cases, the direct momentum transfer from breaking waves to the water flow contributes significantly to wave damping.

  7. The seismology of geothermal regimes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Aki, K.

    1997-04-01

    The authors have been developing seismological interpretation theory and methods applicable to complex structures encountered in geothermal areas for a better understanding of the earth`s geothermal regimes. The questions the y have addressed in their research may be summarized as ``What is going on in the earth`s crust under tectonically active regions; what are the structures and processes responsible for such activities as earthquakes and volcanic eruptions; and how can one capture their essence effectively by means of seismological studies?`` First, the authors found clear evidence for localization of scattered seismic energy in the deep magmatic system of the volcano on the island of Reunion in the Indian Ocean. The seismic coda of local earthquakes show concentrated energy in the intrusive zones as late as 30 to 40 seconds after the origin time. This offers a very effective method for defining a zone of strong heterogeneity on a regional scale, complementary to the high resolution study using trapped modes as pursued in the past project. Secondly, the authors identified about 700 long-period events with various frequencies and durations from the data collected during the past 5 years which included three episodes of eruption. They are applying a finite-element method to the simplest event with the longest period and the shortest duration in order to find the location, geometry and physical properties of their source deterministically. The preliminary result described here suggests that their sources may be a horizontally lying magma-filled crack at a shallow depth under the summit area. In addition to the above work on the Reunion data, they have continued the theoretical and observational studies of attenuation and scattering of seismic waves.

  8. Antecedents of Teachers Fostering Effort within two different management regimes: An assessment-based accountability regime and regime without external pressure on results

    OpenAIRE

    Knut-Andreas Christophersen; Eyvind Elstad; Are Turmo

    2012-01-01

    This article focuses on the comparison of organizational antecedents of teachers' fostering of students' effort in two quite different accountability regimes: one management regime with an external-accountability system and one with no external accountability devices. The methodology involves cross-sectional surveys from two different management systems: (1) teachers working under assessment-based accountability (N = 236) and (2) folk–high school teachers who work without tests and examinatio...

  9. Antecedents of Teachers Fostering Effort within two different management regimes: An assessment-based accountability regime and regime without external pressure on results

    Directory of Open Access Journals (Sweden)

    Knut-Andreas Christophersen

    2012-12-01

    Full Text Available This article focuses on the comparison of organizational antecedents of teachers' fostering of students' effort in two quite different accountability regimes: one management regime with an external-accountability system and one with no external accountability devices. The methodology involves cross-sectional surveys from two different management systems: (1 teachers working under assessment-based accountability (N = 236 and (2 folk–high school teachers who work without tests and examinations and, thereby, without external accountability devices (N = 366. The purpose of the study is to estimate the path coefficients in structural equation modeling in the two regimes and compare the significance of relationships between concepts in the structural models. Through this comparison, inferences are drawn suggesting how accountability repercussions and other leadership organizational antecedents may influence teachers' fostering of students' efforts and how qualitative aspects among school professionals may influence the fostering of effort. Implications for practice and directions for future research are discussed.Christopherson, K, Elstad, E, & Turmo, A. (2012. Antecedents of teachers fostering effort within two different management regimes: an assessment-based accountability regime and regime without external pressure on results. International Journal of Education Policy and Leadership 7(6. Retrieved from www.ijepl.org.

  10. Transition to ballistic regime for heat transport in helium II

    Energy Technology Data Exchange (ETDEWEB)

    Sciacca, Michele, E-mail: michele.sciacca@unipa.it [Dipartimento Scienze Agrarie e Forestali, Università degli studi di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Catalonia (Spain); Sellitto, Antonio, E-mail: ant.sellitto@gmail.com [Dipartimento di Matematica, Informatica ed Economia, Università della Basilicata, Campus Macchia Romana, 85100 Potenza (Italy); Jou, David, E-mail: david.jou@uab.cat [Departament de Física, Universitat Autònoma de Barcelona, 08193 Bellaterra, Catalonia (Spain); Institut d' Estudis Catalans, Carme 47, 08001 Barcelona, Catalonia (Spain)

    2014-07-04

    The size-dependent and flux-dependent effective thermal conductivity of narrow capillaries filled with superfluid helium is analyzed from a thermodynamic continuum perspective. The classical Landau evaluation of the effective thermal conductivity of quiescent superfluid, or the Gorter–Mellinck regime of turbulent superfluids, is extended to describe the transition to ballistic regime in narrow channels wherein the radius R is comparable to (or smaller than) the phonon mean-free path ℓ in superfluid helium. To do so, we start from an extended equation for the heat flux incorporating non-local terms, and take into consideration a heat slip flow along the walls of the tube. This leads from an effective thermal conductivity proportional to R{sup 2} (Landau regime) to another one proportional to Rℓ (ballistic regime). We consider two kinds of flows: along cylindrical pipes and along two infinite parallel plates. - Highlights: • Heat transport in counterflow helium in the ballistic regime. • The one-fluid model based on the Extended Thermodynamics is used. • The transition from the Landau regime to the ballistic regime. • The transition from quantum turbulence to ballistic regime.

  11. Consumption, investment and life insurance under different tax regimes

    DEFF Research Database (Denmark)

    Bruun, Kenneth

    2013-01-01

    , and compare tax effects on consumption/savings contributions, investment and purchase of life insurance under the regimes. The optimization problems have analytical solutions, which allow for easy comparison of tax effects under the different regimes. To substantiate the results we also present a numerical...

  12. Bargaining among Nations: Culture, History, and Perceptions in Regime Formation.

    Science.gov (United States)

    Lipschutz, Ronnie D.

    1991-01-01

    The formation of regimes (collective international schemes) for managing global problems depends on culture, history, and perceptions. The ways in which these elements affect bargaining among nations over issues of the global commons are discussed. Implications are reviewed for a regime to deal with atmospheric conditions and global warming. (SLD)

  13. Disciplinary Regimes of "Care" and Complementary Alternative Education

    Science.gov (United States)

    Thomson, Pat; Pennacchia, Jodie

    2016-01-01

    In schools, the notion of "care" is often synonymous with welfare and disciplinary regimes. Drawing on Foucault, and a study of alternative education (AE) across the UK, and looking in depth at two cases of complementary AE, we identify three types of disciplinary regimes at work in schools: (1) dominant performative reward and…

  14. Transition to ballistic regime for heat transport in helium II

    International Nuclear Information System (INIS)

    The size-dependent and flux-dependent effective thermal conductivity of narrow capillaries filled with superfluid helium is analyzed from a thermodynamic continuum perspective. The classical Landau evaluation of the effective thermal conductivity of quiescent superfluid, or the Gorter–Mellinck regime of turbulent superfluids, is extended to describe the transition to ballistic regime in narrow channels wherein the radius R is comparable to (or smaller than) the phonon mean-free path ℓ in superfluid helium. To do so, we start from an extended equation for the heat flux incorporating non-local terms, and take into consideration a heat slip flow along the walls of the tube. This leads from an effective thermal conductivity proportional to R2 (Landau regime) to another one proportional to Rℓ (ballistic regime). We consider two kinds of flows: along cylindrical pipes and along two infinite parallel plates. - Highlights: • Heat transport in counterflow helium in the ballistic regime. • The one-fluid model based on the Extended Thermodynamics is used. • The transition from the Landau regime to the ballistic regime. • The transition from quantum turbulence to ballistic regime

  15. States agree on stronger physical protection regime

    International Nuclear Information System (INIS)

    Full text: Delegates from 89 countries agreed on 8 July to fundamental changes that will substantially strengthen the Convention on the Physical Protection of Nuclear Material (CPPNM). IAEA Director General Mohamed ElBaradei welcomed the agreement in saying 'This new and stronger treaty is an important step towards greater nuclear security by combating, preventing, and ultimately punishing those who would engage in nuclear theft, sabotage or even terrorism. It demonstrates that there is indeed a global commitment to remedy weaknesses in our nuclear security regime.' The amended CPPNM makes it legally binding for States Parties to protect nuclear facilities and material in peaceful domestic use, storage as well as transport. It will also provide for expanded cooperation between and among States regarding rapid measures to locate and recover stolen or smuggled nuclear material, mitigate any radiological consequences of sabotage, and prevent and combat related offences. The original CPPNM applied only to nuclear material in international transport. Conference President Dr. Alec Baer said 'All 89 delegations demonstrated real unity of purpose. They put aside some very genuine national concerns in favour of the global interest and the result is a much improved convention that is better suited to addressing the nuclear security challenges we currently face.' The new rules will come into effect once they have been ratified by two-thirds of the 112 States Parties of the Convention, expected to take several years. 'But concrete actions are already taking place around the world. For more than 3 years, the IAEA has been implementing a systematic Nuclear Security plan, including physical protection activities designed to prevent, detect and respond to malicious acts,' said Anita Nillson, Director of the IAEA's Office of Nuclear Security. The Agency's Nuclear Security Fund, set up after the events of 9/11, has delivered $19.5 million in practical assistance to 121 countries

  16. Boundary between Stable and Unstable Regimes of Accretion. Ordered and Chaotic Unstable Regimes

    CERN Document Server

    Blinova, A A; Lovelace, R V E

    2015-01-01

    We search for the boundary between stable and Rayleigh-Taylor unstable regimes of accretion to magnetized stars in a new set of high grid resolution simulations. We found that the boundary between stable and unstable regimes is mainly determined by the ratio of the corotation radius r_cor (where the Keplerian angular velocity in the disc matches the angular velocity of the star) to the magnetospheric radius r_m (where the magnetic stress in the magnetosphere matches the matter stress in the disc). Instability is stronger when r_cor is larger with respect to r_m, that is, when the gravitational force is larger than the centrifugal force at the inner disc. In the cases of a small tilt of the magnetosphere, Theta=5 deg, and a small alpha-parameter of viscosity, alpha=0.02, the boundary is located at r_cor approx. 1.4 r_m. Instability becomes stronger at higher values of viscosity, and occurs at lower values of r_cor/r_m. At higher values of Theta, the variability associated with instability decreases. Simulation...

  17. An Examination of the Nature of Global MODIS Cloud Regimes

    Science.gov (United States)

    Oreopoulos, Lazaros; Cho, Nayeong; Lee, Dongmin; Kato, Seiji; Huffman, George J.

    2014-01-01

    We introduce global cloud regimes (previously also referred to as "weather states") derived from cloud retrievals that use measurements by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard the Aqua and Terra satellites. The regimes are obtained by applying clustering analysis on joint histograms of retrieved cloud top pressure and cloud optical thickness. By employing a compositing approach on data sets from satellites and other sources, we examine regime structural and thermodynamical characteristics. We establish that the MODIS cloud regimes tend to form in distinct dynamical and thermodynamical environments and have diverse profiles of cloud fraction and water content. When compositing radiative fluxes from the Clouds and the Earth's Radiant Energy System instrument and surface precipitation from the Global Precipitation Climatology Project, we find that regimes with a radiative warming effect on the atmosphere also produce the largest implied latent heat. Taken as a whole, the results of the study corroborate the usefulness of the cloud regime concept, reaffirm the fundamental nature of the regimes as appropriate building blocks for cloud system classification, clarify their association with standard cloud types, and underscore their distinct radiative and hydrological signatures.

  18. Marine regime shifts: drivers and impacts on ecosystems services

    Science.gov (United States)

    Rocha, J.; Yletyinen, J.; Biggs, R.; Blenckner, T.; Peterson, G.

    2015-01-01

    Marine ecosystems can experience regime shifts, in which they shift from being organized around one set of mutually reinforcing structures and processes to another. Anthropogenic global change has broadly increased a wide variety of processes that can drive regime shifts. To assess the vulnerability of marine ecosystems to such shifts and their potential consequences, we reviewed the scientific literature for 13 types of marine regime shifts and used networks to conduct an analysis of co-occurrence of drivers and ecosystem service impacts. We found that regime shifts are caused by multiple drivers and have multiple consequences that co-occur in a non-random pattern. Drivers related to food production, climate change and coastal development are the most common co-occurring causes of regime shifts, while cultural services, biodiversity and primary production are the most common cluster of ecosystem services affected. These clusters prioritize sets of drivers for management and highlight the need for coordinated actions across multiple drivers and scales to reduce the risk of marine regime shifts. Managerial strategies are likely to fail if they only address well-understood or data-rich variables, and international cooperation and polycentric institutions will be critical to implement and coordinate action across the scales at which different drivers operate. By better understanding these underlying patterns, we hope to inform the development of managerial strategies to reduce the risk of high-impact marine regime shifts, especially for areas of the world where data are not available or monitoring programmes are not in place.

  19. Shearing box simulations in the Rayleigh unstable regime

    CERN Document Server

    Nauman, Farrukh

    2015-01-01

    We study the stability properties of Rayleigh unstable flows both in the purely hydrodynamic and magnetohydrodynamic (MHD) regimes for two different values of the shear $q=2.1, 4.2$ ($q = - d\\ln\\Omega / d\\ln r$) and compare it with the Keplerian case $q=1.5$. The Rayleigh stability criterion states that hydrodynamic shear flows are stable for $q2$ regime as the volume averaged velocities ($k=0$ mode) are unstable in this regime but the advantage of using a pseudospectral code is that the $k=0$ mode is conserved. We find that the $q>2$ regime is unstable to turbulence both in the hydrodynamic and in the MHD limit (with an initially weak magnetic field). In the $q>2$ regime, the velocity fluctuations dominate the magnetic fluctuations whereas in the $q2$ regime the instability produces primarily velocity fluctuations that cause magnetic fluctuations, with the causality reversed for the $q<2$ MRI unstable regime. We also find that the magnetic field correlation is increasingly localized as the shear is increa...

  20. Perspectives on the International and Internal Nuclear Security Regime

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Sung Soon [Korea Nuclear Non-proliferation and Control, Daejeon (Korea, Republic of)

    2015-10-15

    The term, 'Nuclear Security' became more familiar to Korean public after the government hosted 2012 Seoul Nuclear Security Summit. Nuclear Security is prevention of, detection of and response to criminal or intentional unauthorized acts involving or directed at nuclear material, other radioactive material, associated facilities, or associated activities. Nuclear Security includes physical protection, security of radioactive sources, nuclear forensics, nuclear smuggling prevention, border monitoring, and cyber security with regard to nuclear and other radiological materials. This abstract will review recent international trends and discuss the nuclear security regime in the Republic of Korea (ROK). The international Nuclear Security Regime has been strengthened. The upcoming Chicago Summit in 2016 and the entry into force of the Amendment of Convention on Physical Protection of Nuclear Materials (CPPNM) will bring major changes in nuclear security. The Republic of Korea hosted the 2012 Seoul Summit and strengthened domestic regime to meet international standards. The ROK has worked hard to contribute to the international security regime and to establish a robust domestic security regime against terrorist threats. Even if the nuclear security regime is robust, Risk-informed Nuclear Security management should be established to meet international standards and to implement effective as well as an efficient nuclear security regime.

  1. Conceptualization of UN Peacekeeping as an International Regime

    Directory of Open Access Journals (Sweden)

    Jana Urbanovská

    2012-12-01

    Full Text Available It is widely recognized that UN peacekeeping operations are an undertheorized topic. In this respect, scholars call to devote more attention to the incorporation of the study of UN peacekeeping operations into the framework of international relations theories. The article responds to these calls and suggests conceptualizing UN peacekeeping as an international regime. Some authors have already referred to UN peacekeeping as an international regime, however, the references have been rather fragmentary and there is no detailed identification of individual dimensions of this regime. The article uses the conception of Stephen Krasner who defines regimes as “principles, norms, rules, and decision-making procedures around which actors’ expectations converge in a given area of international relations” to carefully identify and characterize the dimensions of the UN peacekeeping regime. The conceptualization of UN peacekeeping as an international regime is understood as a first and necessary step to opening new ground to the theoretical study of UN peacekeeping operations within the regime analysis.

  2. The NPT regime: Progress and promises

    International Nuclear Information System (INIS)

    Full text: Thesis. The 'NPT regime' has arrived at a fateful crossroads. Though extended indefinitely in 1995, its future is my no means secure. The future 'progress' of this treaty will depend upon whether the 'promises' of its States parties are fully implemented and, eventually, upon the treaty's success in achieving fully universal membership. Challenges The treaty faces many short-term and longer-term challenges: Short term - The first Preparatory Committee meeting for the 2005 Review Conference will meet next year. NNWS will want to see some evidence of progress on nuclear disarmament (Art. VI), along the lines prescribed in the 13 'practical steps' agreed at the last Review Conference. Yet progress has been set back by: uncertainties over the future of the ABM Treaty; the failure of START II and the CTBT to enter into force; the lack of a FISMAT treaty and a treaty establishing a NWFZ in Central Asia; continued qualitative improvements in nuclear weapons; hints that nuclear testing may one day resume; the persistence of doctrines of first-use, pre-emptive use, and use against states that use CBW. Other compliance-related questions will arise over safeguards (e.g. the inability of the IAEA to conduct inspections in the DPRK; signs of a breakdown of the norm of full-scope IAEA safeguards, e.g. in South Asia). There are also concerns over the implementation of non-proliferation commitments (e.g. persisting allegations about nuclear weapon programmes in existing NNWS). The terrorist attacks in New York and Washington, D.C. on 11 September should also serve as a reminder of the new terrorist dangers relating to the possible use of weapons of mass destruction and unorthodox delivery systems. Longer term - Selectivity in the enforcement of NPT norms; unilateralism; IAEA funding uncertainties and shortfalls; difficulties in reaching universal membership (India, Pakistan, and Israel); continuing compliance problems with respect to both non-proliferation and

  3. Past and Future Drought Regimes in Turkey

    Science.gov (United States)

    Sen, Burak; Topcu, Sevilay; Turkes, Murat; Sen, Baha

    2010-05-01

    Climate variability in the 20th century was characterized by apparent precipitation variability at both temporal and spatial scales. In addition to the well-known characteristic seasonal and year-to-year variability, some marked and long-term changes in precipitation occurred in Turkey, particularly after the early 1970s. Drought, originating from a deficiency of precipitation over an extended time period (which is usually a season or more) has become a recurring phenomenon in Turkey in the past few decades. Spatially coherent with the significant drought events since early 1970s, water stress and shortages for all water user sectors have also reached their critical points in Turkey. Analyzing the historical occurrence of drought provides an understanding of the range of climate possibilities for a country, resulting in more informed management decision-making. However, future projections about spatial and temporal changes in drought characteristics such as frequency, intensity and duration can be challenging for developing appropriate mitigation and adaptation strategies. Hence, the objectives of this study are (i) to analyze the spatial and temporal dimensions of historical droughts in Turkey, (2) to predict potential intensity, frequency and duration of droughts in Turkey for the future (2070-2100). The Standardized Precipitation Index (SPI) and the Percent to Normal Index (PNI) have been used to assess the drought characteristics. Rainfall datasets for the reference period, 1960-1990, were acquired from 52 stations (representative of all kinds of regions with different rainfall regimes in the country) of the Turkish State Meteorological Service (TSMS). The future rainfall series for the 2070-2100 period were simulated using a regional climate model (RegCM3) for IPCC's SRESS-A2 scenario conditions. For verification of RegCM3 simulations, the model was performed for the reference period and simulated rainfall data were used for computing two drought indices (SPI

  4. Considerations on nonproliferation regime meeting in a changing world

    Energy Technology Data Exchange (ETDEWEB)

    Kurihara, Hiroyoshi; Kikuchi, Masahiro [Nuclear Material Control Center, Tokyo (Japan)

    1994-12-31

    This paper summarizes the past history of worldwide nonproliferation regime, then proposes the future improvements on the regime. Present worldwide nonproliferation regime have been formulated during the cold war era. Therefore, the structure and measures of the regime were heavily influenced by the features of cold war era. Though the cold war was over, still new international order does not seem to be on the horizon, we need to review the present regime and to improve the regime compatible to new world situation. Generally speaking, the nonproliferation regime have gained moderate success so far. We could point out the following features as a kind of success: (1) No increase of overt Nuclear Weapon State (NWS), (2) All five NWSs have finally participated to the NPT, (3) South Africa has destroyed its nuclear weapons and became Non-Nuclear Weapon State (NNWS), (4) Successful conclusions of some regional arrangements, such as Tlatelolco, Ralotonga, and (5) Strengthening of export control on sensitive items. On the other hand, we recognize the following points as the failures of the regime. (6) India, Pakistan and Israel reject to join the NPT, (7) Existence of some violation against NPT regime, i.e. Iraqi case and DPRK case, (8) Insufficient effective measures against brain drain problem, (9) Risk exists for the long term extension of NPT, and (10) Insufficient flexibility to meet changing boundary conditions. We would propose the various measures for strengthening to meet changing boundary conditions, as follows: (11) Measures to be taken along with future civil use of Plutonium, (12) Strengthening and rationalizing international safeguards, (13) Countermeasures for emerging new types of nuclear proliferation, (14) Strengthening nuclear material control in NWS, (15) Measures to be taken for nuclear material from dismantled nuclear weapons, and (16) Nuclear disarmament. (author).

  5. Laserlike and atomlike regimes in a one-atom laser

    OpenAIRE

    Boozer, A. D.

    2008-01-01

    We consider a three-level model of a one-atom laser, and show that there are two limiting regimes of parameter space, one in which the system behaves like a conventional laser and one in which the system exhibits novel quantum properties. We show that in the first limiting regime, the model can be approximated by semiclassical laser theory, and in the second limiting regime the model can be approximated as an effective two-level atom. We also perform numerical simulations that confirm the lim...

  6. Diversity-Multiplexing Tradeoff in the Low-SNR Regime

    CERN Document Server

    Loyka, Sergey

    2011-01-01

    An extension of the popular diversity-multiplexing tradeoff framework to the low-SNR (or wideband) regime is proposed. The concept of diversity gain is shown to be redundant in this regime since the outage probability is SNR-independent and depends on the multiplexing gain and the channel power gain statistics only. The outage probability under the DMT framework is obtained in an explicit, closed form for a broad class of channels. The low and high-SNR regime boundaries are explicitly determined for the scalar Rayleigh-fading channel, indicating a significant limitation of the SNR-asymptotic DMT when the multiplexing gain is small.

  7. Nonlinear Regime of a Single-mode CSR Instability

    International Nuclear Information System (INIS)

    Close to the shielding threshold of synchrotron radiation in a toroidal waveguide the coherent synchrotron radiation (CSR) instability may be driven by a single synchronous mode. The linear analysis of the problem is presented elsewhere. In this paper we study a nonlinear regime of the single-mode CSR instability. We show that in the nonlinear regime the instability is described by a system of equations which, after a proper scaling, coincides with the 1D FEL instability theory. We present numeric and analytic analysis of the non-linear regime for the time interval large compared with the damping time taking into account radiation damping and diffusion due to the quantum fluctuations

  8. Formations and transformations of language regimes: Turkey, a case study

    OpenAIRE

    Balçık, Mehmet Berk; Balcik, Mehmet Berk

    2009-01-01

    There are two main aims of this dissertation: to present a legal and ideological history of the formation of the language regime in Turkey in the Republican period; and to analyze its transformation in the post-1980 era. A language regime is defined in this dissertation as a de jure or de facto regulation of the linguistic behavior, in its content or in its status, within a space of communicative action, such as that of a nation-state or a speech group. In other words, a language regime is a ...

  9. Raman amplification in the broken-wave regime

    CERN Document Server

    Farmer, John P

    2015-01-01

    In regimes far beyond the wavebreaking theshold of Raman amplification, we show that significant amplifcation can occur after the onset of wavebreaking, before phase mixing destroys the coupling between pump and probe. The amplification efficiency in this regime is therefore strongly dependent on the energy-transfer rate when wavebreaking occurs, and is, as such, sensitive to both the probe amplitude and profile. In order to access the higher-efficiency broken-wave regime, a short, intense probe is required. Parameter scans show the marked difference in behaviour compared to below wavebreaking, where longer, more energetic pulses lead to improved efficiencies.

  10. Policy Ideas, Knowledge Regimes and Comparative Political Economy

    DEFF Research Database (Denmark)

    Campbell, John L.; Pedersen, Ove K.

    2015-01-01

    Despite much attention to how ideas affect policy making, where these ideas come from is a blind spot in comparative political economy. We show that an important source of policy ideas are knowledge regimes—fields of policy research organizations. We show as well that the organization of knowledge...... regimes is heavily influenced by the organization of their surrounding political economies such that knowledge regimes have particular national characters. Furthermore, when people perceive that the utility of their knowledge regime for the rest of the political economy breaks down, they often try......, France and Germany. Theoretical implications are explored for two literatures in comparative political economy: ideational analysis and the varieties of capitalism....

  11. Regime-Switching Risk: To Price or Not to Price?

    Directory of Open Access Journals (Sweden)

    Tak Kuen Siu

    2011-01-01

    “normative” issues to be addressed in pricing contingent claims under a Markovian, regime-switching, Black-Scholes-Merton model. We address this issue using a minimal relative entropy approach. Firstly, we apply a martingale representation for a double martingale to characterize the canonical space of equivalent martingale measures which may be viewed as the largest space of equivalent martingale measures to incorporate both the diffusion risk and the regime-switching risk. Then we show that an optimal equivalent martingale measure over the canonical space selected by minimizing the relative entropy between an equivalent martingale measure and the real-world probability measure does not price the regime-switching risk. The optimal measure also justifies the use of the Esscher transform for option valuation in the regime-switching market.

  12. Regime shifts and resilience in China's coastal ecosystems.

    Science.gov (United States)

    Zhang, Ke

    2016-02-01

    Regime shift often results in large, abrupt, and persistent changes in the provision of ecosystem services and can therefore have significant impacts on human wellbeing. Understanding regime shifts has profound implications for ecosystem recovery and management. China's coastal ecosystems have experienced substantial deterioration within the past decades, at a scale and speed the world has never seen before. Yet, information about this coastal ecosystem change from a dynamics perspective is quite limited. In this review, I synthesize existing information on coastal ecosystem regime shifts in China and discuss their interactions and cascading effects. The accumulation of regime shifts in China's coastal ecosystems suggests that the desired system resilience has been profoundly eroded, increasing the potential of abrupt shifts to undesirable states at a larger scale, especially given multiple escalating pressures. Policy and management strategies need to incorporate resilience approaches in order to cope with future challenges and avoid major losses in China's coastal ecosystem services.

  13. Spacetime-noncommutativity regime of Loop Quantum Gravity

    CERN Document Server

    Amelino-Camelia, Giovanni; Ronco, Michele; Cesarini, Lorenzo; Lecian, Orchidea Maria

    2016-01-01

    A recent study by Bojowald and Paily provided a path toward the identification of an effective quantum-spacetime picture of Loop Quantum Gravity, applicable in the "Minkowski regime", the regime where the large-scale (coarse-grained) spacetime metric is flat. A pivotal role in the analysis is played by Loop-Quantum-Gravity-based modifications to the hypersurface deformation algebra, which leave a trace in the Minkowski regime. We here show that the symmetry-algebra results reported by Bojowald and Paily are consistent with a description of spacetime in the Minkowski regime given in terms of the $\\kappa$-Minkowski noncommutative spacetime, whose relevance for the study of the quantum-gravity problem had already been proposed for independent reasons.

  14. A new regime for future telecommunication network operations

    NARCIS (Netherlands)

    Gustafsson, S.; Trommelen, P.H.; Vos, C. de

    2010-01-01

    The increasingly crucial role that telecommunications plays in today's information society calls for a new regime for telecommunication network operations. An unbundling of business roles and associated responsibilities is proposed, providing more economic network operations and higher availability

  15. The Hadley and Rossby regimes in a spherical atmosphere

    Science.gov (United States)

    Feldstein, S. B.; Clark, J. H. E.

    1985-01-01

    The properties of the steady Hadley and Rossby regimes for a thermally forced rotating fluid on a sphere are studied. The two layer modified geostrophic model is employed which allows for thermal advection by the divergent wind and time dependent static stability. Heating processes are parameterized using the Newtonian approximation and Rayleigh friction is accounted for. The equations are transformed to spectral form using spherical harmonics and then truncated retaining a simple axisymmetric state and initial, one wave. A time independent Hadley circulation is obtained which is neutral to axisymmetric disturbances but unstable to wave like perturbations for intermediate values of the meridional temperature gradient, indicating the existence of both an upper and lower symmetric Hadley regime. An analytical solution for the steady Rossby circulation is determined for values of the meridional temperature gradient where the Hadley regime is unstable. Linear perturbation theory is used to show that within the steady Rossby regime two or more waves cannot exist simultaneously.

  16. Capillary Breakup of a Liquid Bridge: Identifying Regimes and Transitions

    CERN Document Server

    Li, Yuan

    2016-01-01

    Computations of the breakup of a liquid bridge are used to establish the limits of applicability of similarity solutions derived for different breakup regimes. These regimes are based on particular viscous-inertial balances, that is different limits of the Ohnesorge number $Oh$. To accurately establish the transitions between regimes, the minimum bridge radius is resolved through four orders of magnitude using a purpose-built multiscale finite element method. This allows us to construct a quantitative phase diagram for the breakup phenomenon which includes the appearance of a recently discovered low-$Oh$ viscous regime. The method used to quantify the accuracy of the similarity solutions allows us to identify a number of previously unobserved features of the breakup, most notably an oscillatory convergence towards the viscous-inertial similarity solution. Finally, we discuss how the new findings open up a number of challenges for both theoretical and experimental analysis.

  17. Determination of three characteristic regimes of weakly charged polyelectrolytes monolayers

    International Nuclear Information System (INIS)

    We have demonstrated that monolayer films of randomly charged polystyrene sulfonated acid (PSSA) can be produced by the Langmuir technique, and observed the micro-domain structures, produced by the phase separation of electrostatically charged moieties and the hydrophobic moieties. Using atomic force microscopy and Langmuir isotherm, we found three specific regimes for the polyelectrolytes with various degrees of sulfonation (4-35%); very low charged PSSA (4-5%) in the hydrophobic regime, moderately charged PSSA (6-16%) which possessed a well-balanced nature between electrostatic and the hydrophobic interactions, and strongly amphiphilic nature of PSSA (6-16%) in the ionomer regime. Finally, we could categorize PSSA 35% in the polyelectrolyte regime, due to the dominance of the electrostatic interactions over the hydrophobic interactions

  18. Evolving International Trade and Monetary Regimes and Related Policy Issues

    OpenAIRE

    Kumiharu Shigehara

    1991-01-01

    This essay focuses on some aspects of policy issues relating to evolving international trade and monetary regimes, and patterns of national saving and investment balances conducive to better global economic performance.

  19. Quantifying flooding regime in floodplain forests to guide river restoration

    OpenAIRE

    Christian O. Marks; Keith H Nislow; Magilligan, Francis J.

    2014-01-01

    Abstract Determining the flooding regime needed to support distinctive floodplain forests is essential for effective river conservation under the ubiquitous human alteration of river flows characteristic of the Anthropocene Era. At over 100 sites throughout the Connecticut River basin, the largest river system in New England, we characterized species composition, valley and channel morphology, and hydrologic regime to define conditions promoting distinct floodplain forest assemblages. Species...

  20. Shock-Induced Flows through Packed Beds: Transient Regimes

    CERN Document Server

    Shtemler, Yuri M; Britan, Alex

    2006-01-01

    The early stage of the transient regimes in the shock-induced flows within solid-packed beds are investigated in the linear longwave and high-frequency approximation. The transient resistance law is refined as the Duhameltime integral that follows from the general concept of dynamic tortuosity and compressibility of the packed beds. A closed-form solution is expected to describe accurately the early stage of the transient regime flow and is in qualitative agreement with available experimental data.

  1. Capital Controls and the Timing of Exchange Regime Collapse

    OpenAIRE

    Daekuen Park; Jeffrey Sachs

    1987-01-01

    This paper investigates the nature of balance of payments crises in regimes with capital controls. It extends earlier work on capital controls by assuming that households manage their consumption and asset portfolios to maximize intertemporal utility. Our main result is that capital controls are effective in delaying, but not preventing, a breakdown of a fixed exchange rate regime in the presence of money-financed fiscal deficits.

  2. Constructing a Transnational Timber Legality Assurance Regime: Architecture, Accomplishments, Challenges

    OpenAIRE

    Overdevest, C.; Zeitlin, J

    2013-01-01

    The emerging transnational timber legality assurance regime comprises a set of interrelated policy instruments, both public and private, aimed at controlling trade in illegally logged wood and wood products. The potentially productive interactions among these instruments in the emerging forestry regime create prospects for engendering learning, stimulating cross-fertilization, and enhancing accountability. In this article, we analyze the EU's Forest Law Enforcement Governance and Trade (FLEGT...

  3. Were there regime switches in U.S. monetary policy?

    OpenAIRE

    Christopher A. Sims; Zha, Tao

    2004-01-01

    A multivariate model, identifying monetary policy and allowing for simultaneity and regime switching in coefficients and variances, is confronted with U.S. data since 1959. The best fit is with a model that allows time variation in structural disturbance variances only. Among models that also allow for changes in equation coefficients, the best fit is for a model that allows coefficients to change only in the monetary policy rule. That model allows switching among three main regimes and one r...

  4. Laboratory experiment on boundaries of upper stage plane bed regime

    Science.gov (United States)

    Zrostlík, Štěpán; Matoušek, Václav

    2016-04-01

    Results are discussed of laboratory experiments on criteria determining the transition between the regime of dunes and the upper stage plane bed (UPB) regime and the transition between the UPB regime and the regime of wavy flow. The experiments were carried for 3 fractions of plastic material and two fractions of glass beads in a broad range of flow conditions (different discharges of water and solids and longitudinal bed slopes) in a tilting flume. The experiments reveal that, contrary to expectations, a constant value of the Shields parameter is not an appropriate criterion for the transition between the dune regime and the UPB regime. Furthermore, the transition appears to be insensitive to the total discharge of solids and water. Instead, the criterion seems to be well represented by a constant value of the average transport concentration of sediment (the ratio of volumetric discharge of solids and volumetric discharge of mixture). The experimental results exhibit a very tight correlation between the transport concentration and the longitudinal bed slope. Hence, a constant value of the bed slope can be considered an appropriate criterion for the transition. The transition between the UPB regime and the wavy regime (significant waves develop but they are not always standing waves) is found at a constant value of Froude number, which is in agreement with literature, although it is found at a higher value than the literature usually suggests (Fr = 1.2 instead of 1.0). Hence, the transition occurs in the super-critical flow but it is not necessarily associated with the critical flow.

  5. Generating Schemes for Long Memory Processes: Regimes, Aggregation and Linearity

    OpenAIRE

    Davidson, James; Sibbertsen, Philipp

    2002-01-01

    This paper analyses a class of nonlinear time series models exhibiting long memory. These processes exhibit short memory fluctuations around a local mean (regime) which switches randomly such that the durations of the regimes follow a power law. We show that if a large number of independent copies of such a process are aggregated, the resulting processes are Gaussian, have a linear representation, and converge after normalisation to fractional Brownian motion. Two cases arise, a stationary ca...

  6. Et dansk regime for overgang fra uddannelse til arbejde?

    DEFF Research Database (Denmark)

    Jørgensen, Christian Helms

    2008-01-01

    I dette kapitel vil jeg først gennemgå en række forskningstilgange som på forskellig måde kan begribe de særlige træk ved unges overgang i Danmark i det man kan kalde et dansk 'regime for overgang' (transition regime). Dernæst følger en mere beskrivende gennemgang af det danske uddannelsessystem ...

  7. Real Output and Prices Adjustments under Different Exchange Rate Regimes

    OpenAIRE

    Rajmund MIRDALA

    2013-01-01

    Exchange rate regimes evolution in the European transition economies refers to one of the most crucial policy decision in the beginning of the 1990s employed during the initial stages of the transition process. During the period of last two decades we may identify some crucial milestones in the exchange rate regimes evolution in the European transition economies. due to existing diversity in exchange rate arrangements in the European transition economies in the pre-ERM2 period there seems to ...

  8. Sensitivity of streamflows to hydroclimatic fluctuations: resilience and regime shifts

    Science.gov (United States)

    Botter, Gianluca; Basso, Stefano; Rodriguez-Iturbe, Ignacio; Rinaldo, Andrea

    2016-04-01

    Landscape and climate alterations foreshadow global-scale shifts of river flow regimes. However, a theory that identifies the range of foreseen impacts on streamflows resulting from inhomogeneous forcings and sensitivity gradients across diverse regimes is lacking. In this contribution, we use a dimensionless index embedding simple climate and landscape attributes (the ratio of the mean interarrival of streamflow-producing rainfall events and the mean catchment response time) to discriminate erratic regimes with enhanced intra-seasonal streamflow variability from persistent regimes endowed with regular flow patterns. The proposed classification is successfully applied to 110 seasonal streamflow distributions observed in 44 catchments of the Alps and the United States, allowing the identification of emerging patterns in space and time. In the same framework, the impact of multi-scale fluctuations of the underlying climatic drivers (temperature, precipitation) on the streamflow distributions can be analyzed. Theoretical and empirical data show that erratic regimes, typical of rivers with low mean discharges, are highly resilient in that they hold a reduced sensitivity to variations in the external forcing. Specific temporal trajectories of streamflow distributions and flow regime shifts driven by land-cover change and rainfall patterns can be also evidenced. The approach developed offers an objective basis for the analysis and prediction of the impact of climate/landscape change on water resources.

  9. International regime formation: Ozone depletion and global climate change

    Energy Technology Data Exchange (ETDEWEB)

    Busmann, N.E.

    1994-03-01

    Two theoretical perspectives, neorealism and neoliberal institutionalism, dominate in international relations. An assessment is made of whether these perspectives provide compelling explanations of why a regime with specific targets and timetables was formed for ozone depletion, while a regime with such specificity was not formed for global climate change. In so doing, the assumptions underlying neorealism and neoliberal institutionalism are examined. A preliminary assessment is offered of the policymaking and institutional bargaining process. Patterns of interstate behavior are evolving toward broader forms of cooperation, at least with regard to global environmental issues, although this process is both slow and cautious. State coalitions on specific issues are not yet powerful enough to create a strong community of states in which states are willing to devolve power to international institutions. It is shown that regime analysis is a useful analytic framework, but it should not be mistaken for theory. Regime analysis provides an organizational framework offering a set of questions regarding the principles and norms that govern cooperation and conflict in an issue area, and whether forces independent of states exist which affect the scope of state behavior. An examination of both neorealism and neoliberal institutionalism, embodied by four approaches to regime formation, demonstrates that neither has sufficient scope to account for contextual dynamics in either the ozone depletion or global climate change regime formation processes. 261 refs.

  10. Development of Risk Assessment Methodology for State's Nuclear Security Regime

    International Nuclear Information System (INIS)

    Threats of nuclear terrorism are increasing after 9/11 terrorist attack. Treats include nuclear explosive device (NED) made by terrorist groups, radiological damage caused by a sabotage aiming nuclear facilities, and radiological dispersion device (RDD), which is also called 'dirty bomb'. In 9/11, Al Qaeda planed to cause radiological consequences by the crash of a nuclear power plant and the captured airplane. The evidence of a dirty bomb experiment was found in Afganistan by the UK intelligence agency. Thus, the international communities including the IAEA work substantial efforts. The leaders of 47 nations attended the 2010 nuclear security summit hosted by President Obama, while the next global nuclear summit will be held in Seoul, 2012. Most states established and are maintaining state's nuclear security regime because of the increasing threat and the international obligations. However, each state's nuclear security regime is different and depends on the state's environment. The methodology for the assessment of state's nuclear security regime is necessary to design and implement an efficient nuclear security regime, and to figure out weak points. The IAEA's INPRO project suggests a checklist method for State's nuclear security regime. The IAEA is now researching more quantitative methods cooperatively with several countries including Korea. In this abstract, methodologies to evaluate state's nuclear security regime by risk assessment are addressed

  11. Oscillations of a highly discrete breather with a critical regime

    Science.gov (United States)

    Coquet; Remoissenet; Dinda

    2000-10-01

    We analyze carefully the essential features of the dynamics of a stationary discrete breather in the ultimate degree of energy localization in a nonlinear Klein-Gordon lattice with an on-site double-well potential. We demonstrate the existence of three different regimes of oscillatory motion in the breather dynamics, which are closely related to the motion of the central particle in an effective potential having two nondegenerate wells. In given parameter regions, we observe an untrapped regime, in which the central particle executes large-amplitude oscillations from one to the other side of the potential barrier. In other parameter regions, we find the trapped regime, in which the central particle oscillates in one of the two wells of the effective potential. Between these two regimes we find a critical regime in which the central particle undergoes several temporary trappings within an untrapped regime. Importantly, our study reveals that in the presence of purely anharmonic coupling forces, the breather compactifies, i.e., the energy becomes abruptly localized within the breather.

  12. Stochastic Parametrisations and Regime Behaviour of Atmospheric Models

    Science.gov (United States)

    Arnold, Hannah; Moroz, Irene; Palmer, Tim

    2013-04-01

    The presence of regimes is a characteristic of non-linear, chaotic systems (Lorenz, 2006). In the atmosphere, regimes emerge as familiar circulation patterns such as the El-Nino Southern Oscillation (ENSO), the North Atlantic Oscillation (NAO) and Scandinavian Blocking events. In recent years there has been much interest in the problem of identifying and studying atmospheric regimes (Solomon et al, 2007). In particular, how do these regimes respond to an external forcing such as anthropogenic greenhouse gas emissions? The importance of regimes in observed trends over the past 50-100 years indicates that in order to predict anthropogenic climate change, our climate models must be able to represent accurately natural circulation regimes, their statistics and variability. It is well established that representing model uncertainty as well as initial condition uncertainty is important for reliable weather forecasts (Palmer, 2001). In particular, stochastic parametrisation schemes have been shown to improve the skill of weather forecast models (e.g. Berner et al., 2009; Frenkel et al., 2012; Palmer et al., 2009). It is possible that including stochastic physics as a representation of model uncertainty could also be beneficial in climate modelling, enabling the simulator to explore larger regions of the climate attractor including other flow regimes. An alternative representation of model uncertainty is a perturbed parameter scheme, whereby physical parameters in subgrid parametrisation schemes are perturbed about their optimal value. Perturbing parameters gives a greater control over the ensemble than multi-model or multiparametrisation ensembles, and has been used as a representation of model uncertainty in climate prediction (Stainforth et al., 2005; Rougier et al., 2009). We investigate the effect of including representations of model uncertainty on the regime behaviour of a simulator. A simple chaotic model of the atmosphere, the Lorenz '96 system, is used to study

  13. Positron acceleration in doughnut wakefields in the blowout regime

    Science.gov (United States)

    Vieira, Jorge; Mendonca, Jose; Fonseca, Ricardo; Silva, Luis

    2014-10-01

    Most important plasma acceleration results were reached in the so called bubble or blowout regime. Although ideally suited for electron acceleration, it has been recognized that non-linear regimes are not adequate to accelerate positrons. New configurations enabling positron acceleration in non-linear regimes would therefore open new research paths for future plasma based collider configurations. In this work, we explore, analytically and through 3D OSIRIS simulations, a novel configuration for positron acceleration in strongly non-linear laser wakefield excitation regimes using Laguerre-Gaussian laser drivers to drive doughnut shaped wakefields with positron focusing and accelerating fields. We demonstrate that positron focusing-fields can be up to an order of magnitude larger than electron focusing in the spherical blowout regime. The amplitude of the accelerating fields is similar to the spherical blowout. Simulations demonstrate laser self-guiding and stable positron acceleration until the laser energy has been exhausted to the plasma. Other realisations of the scheme, using two Gaussian laser pulses, will also be explored. FCT Grant No EXPL/FIS-PLA/0834/2012 and European Research Council ERC-2010-AdG Grant No. 267841.

  14. Early signatures of regime shifts in complex dynamical systems

    Indian Academy of Sciences (India)

    Indrani Bose; Mainak Pal

    2015-02-01

    A large number of studies have recently been carried out on the early signatures of regime shifts in a number of dynamical systems, e.g., ecosystems, the climate, fish and wildlife populations, financial markets, complex diseases and gene circuits. The underlying model in most cases is that of the fold-bifurcation in which a sudden regime shift occurs at a bifurcation point. The shift involves a discontinuous jump from one type of stable steady state to another. The dynamics of natural systems have both deterministic and stochastic components. The early signatures of abrupt regime shifts include the critical slowing down as a transition point is approached, rising variance and the lag-1 autocorrelation function, increased skewness of the steady-state probability distribution and the ratio of two mean first passage times for the exits from the stable steady states as the bifurcation point is approached. Noise-induced regime shifts are also possible for which the vicinity of the bifurcation point is not essential. In this paper, we review examples of regime shifts in natural systems and the associated early signatures. We further discuss how such approaches provide useful insights on a cell biological process involving the fold-bifurcation.

  15. Shear Capacity as Prognostic of Nocturnal Boundary Layer Regimes

    Science.gov (United States)

    van Hooijdonk, Ivo; Donda, Judith; Bosveld, Fred; Moene, Arnold; Clercx, Herman; van de Wiel, Bas

    2015-04-01

    After sunset the surface temperature can drop rapidly in some nights and may lead to ground frost. This sudden drop is closely related to the occurrence of fundamentally different behaviour of turbulence in the nocturnal boundary layer. Recent theoretical findings predict the appearance of two different regimes: the continuously turbulent (weakly stable) boundary layer and the relatively 'quiet' (very stable) boundary layer. Field observations from a large number of nights (approx. 4500 in total) are analysed using an ensemble averaging technique. The observations support the existence of these two fundamentally different regimes: weakly stable (turbulent) nights rapidly reach a steady state (within 2-3 hours). In contrast, very stable nights reach a steady state much later after a transition period (2-6 hours). During this period turbulence is weak and non-stationary. To characterise the regime a new parameter is introduced: the Shear Capacity. This parameter compares the actual shear after sunset with the minimum shear needed to sustain continuous turbulence. In turn, the minimum shear is dictated by the heat flux demand at the surface (net radiative cooling), so that the Shear Capacity combines flow information with knowledge on the boundary condition. It is shown that the Shear Capacity enables prediction of the flow regimes. The prognostic strength of this non-dimensional parameter appears to outperform the traditional ones like z/L and Ri as regime indicator.

  16. THE IMPACT OF THE GLOBAL NUCLEAR SAFETY REGIME IN BRAZIL

    International Nuclear Information System (INIS)

    A turning point of the world nuclear industry with respect to safety occurred due to the accident at Chernobyl, in 1986. A side from the tragic personal losses and the enormous financial damage, the Chernobyl accident has literally demonstrated that ''a nuclear accident anywhere is an accident everywhere''. The impact was felt immediately by the nuclear industry, with plant cancellations (e.g. Austria), elimination of national programs (e.g. Italy) and general construction delays. However, the reaction of the nuclear industry was equally immediate, which led to the proposal and establishment of a Global Nuclear Safety Regime. This regime is composed of biding international safety conventions, globally accepted safety standard, and a voluntary peer review system. In a previous work, the author has presented in detail the components of this Regime, and briefly discussed its impact in the Brazilian nuclear power organizations, including the Regulatory Body. This work, on the opposite, briefly reviews the Global Nuclear Safety Regime, and concentrates in detail in the discussion of its impact in Brazil, showing how it has produced some changes, and where the peer pressure regime has failed to produce real results

  17. Early Regimes of Water Capillary Flow in Slit Silica Nanochannels

    DEFF Research Database (Denmark)

    Oyarzua, Elton; Walther, Jens Honore; Mejia, Andres;

    2015-01-01

    Molecular dynamics simulations are conducted to investigate the initial stages of spontaneous imbibitionof water in slit silica nanochannels surrounded by air. An analysis is performed for the effects of nanoscopicconfinement, initial conditions of liquid uptake and air pressurization on the dyna......Molecular dynamics simulations are conducted to investigate the initial stages of spontaneous imbibitionof water in slit silica nanochannels surrounded by air. An analysis is performed for the effects of nanoscopicconfinement, initial conditions of liquid uptake and air pressurization...... on the dynamics of capillaryfilling. The results indicate that the nanoscale imbibition process is divided into three main flow regimes:an initial regime where the capillary force is balanced only by the inertial drag and characterized by aconstant velocity and a plug flow profile. In this regime, the meniscus...... formation process plays a centralrole in the imbibition rate. Thereafter, a transitional regime takes place, in which, the force balance hassignificant contributions from both inertia and viscous friction. Subsequently, a regime wherein viscousforces dominate the capillary force balance is attained. Flow...

  18. Hydrological minimal model for fire regime assessment in Mediterranean ecosystem

    Science.gov (United States)

    Ursino, N.; Rulli, M. C.

    2012-04-01

    A new model for Mediterranean forest fire regime assessment is presented and discussed. The model is based on the experimental evidence that fire is due to both hydrological and ecological processes and the relative role of fuel load versus fuel moisture is an important driver in fire ecology. Diverse scenarios are analyzed where either the hydrological forcing or the feedback between fire and hydrological characterization of the site is changed. The model outcome demonstrates that the two way interaction between hydrological processes, biology and fire regime drives the ecosystem toward a typical fire regime that may be altered either by an evolution of the biological characterization of the site or by a change of the hydrological forcing. This tenet implies that not every fire regime is compatible with the ecohydrological characterization of the site under study. This means that natural (non antropogenic) fire cannot be modeled as an arbitrary external forcing because the coupled hydrological and biological processes determines its statistical characterization, and conversely, the fire regime affects the soil moisture availability and the outcome of different species competition under possible water stress. The new modelling approach presented here, when provided by a proper model parameterization, can advance the capability in predicting and managing fires in ecosystems influenced by climate and land use changes.

  19. Soil magnetic susceptibility reflects soil moisture regimes and the adaptability of tree species to these regimes

    Science.gov (United States)

    Wang, J.-S.; Grimley, D.A.; Xu, C.; Dawson, J.O.

    2008-01-01

    Flooded, saturated or poorly drained soils are frequently anaerobic, leading to dissolution of the strongly magnetic minerals, magnetite and maghemite, and a corresponding decrease in soil magnetic susceptibility (MS). In this study of five temperate deciduous forests in east-central Illinois, USA, mean surface soil MS was significantly higher adjacent to upland tree species (31 ?? 10-5 SI) than adjacent to floodplain or lowland tree species (17 ?? 10-5 SI), when comparing regional soils with similar parent material of loessal silt. Although the sites differ in average soil MS for each tree species, the relative order of soil MS means for associated tree species at different locations is similar. Lowland tree species, Celtis occidentalis L., Ulmus americana L., Acer saccharinum L., Carya laciniosa (Michx. f.) Loud., and Fraxinus pennsylvanica Marsh. were associated with the lowest measured soil MS mean values overall and at each site. Tree species' flood tolerance rankings increased significantly, as soil MS values declined, the published rankings having significant correlations with soil MS values for the same species groups. The three published classifications of tree species' flood tolerance were significantly correlated with associated soil MS values at all sites, but most strongly at Allerton Park, the site with the widest range of soil drainage classes and MS values. Using soil MS measurements in forests with soil parent material containing similar initial levels of strongly magnetic minerals can provide a simple, rapid and quantitative method to classify soils according to hydric regimes, including dry conditions, and associated plant composition. Soil MS values thus have the capacity to quantify the continuum of hydric tolerances of tree species and guide tree species selection for reforestation. ?? 2007 Elsevier B.V. All rights reserved.

  20. A Markov Switching Regime Model of Malaysia Property Cycle

    Directory of Open Access Journals (Sweden)

    Abdul M. Beksin

    2011-01-01

    Full Text Available Problem statement: Non-linear models such as the Markov Switching regime (MS method of modelling business cycles, in principle can be used to model property cyle. Approach: The MS model can distinguish property cycle in recession and expansion phases and is sufficiently flexible to allow different relationships to apply over these phases. In this study, the Malaysian property cycle is modelled using a MS model. Results: This technique can be used to simultaneously estimate the data generating process of real GDP growth and classify each observation into one of two regimes (i.e., low-growth and high-growth regimes. Conclusions: This finding has important policy implications, since the yield spread was used to generate the time-varying probabilities of the MS model as well as the recession probabilities of the logit model. In other words, a strong relationship exists between interest rates and the business cycle, where interest rates lead the business cycle.

  1. Inhomogeneous stationary and oscillatory regimes in coupled chaotic oscillators.

    Science.gov (United States)

    Liu, Weiqing; Volkov, Evgeny; Xiao, Jinghua; Zou, Wei; Zhan, Meng; Yang, Junzhong

    2012-09-01

    The dynamics of linearly coupled identical Lorenz and Pikovsky-Rabinovich oscillators are explored numerically and theoretically. We concentrate on the study of inhomogeneous stable steady states ("oscillation death (OD)" phenomenon) and accompanying periodic and chaotic regimes that emerge at an appropriate choice of the coupling matrix. The parameters, for which OD occurs, are determined by stability analysis of the chosen steady state. Three model-specific types of transitions to and from OD are observed: (1) a sharp transition to OD from a nonsymmetric chaotic attractor containing random intervals of synchronous chaos; (2) transition to OD from the symmetry-breaking chaotic regime created by negative coupling; (3) supercritical bifurcation of OD into inhomogeneous limit cycles and further evolution of the system to inhomogeneous chaotic regimes that coexist with complete synchronous chaos. These results may fill a gap in the understanding of the mechanism of OD in coupled chaotic systems.

  2. Quantum SASE Regime for X-Ray FEL

    CERN Document Server

    Avetissian, H K

    2005-01-01

    For the X-ray FEL if the amplifying photon energy is larger or comparable to resonance widths caused by an electron beam spreads or by the finite interaction length then the quantum effects may play a significant role [1] and the generation process shifts from the classical to the quantum regime. The recent advancement of high brightness particle and laser beams technology makes achievable the fulfillment of these conditions in the scheme of X-ray Backscatter Compton laser. In this work we consider in general the SASE X-ray FEL in the quantum regime of amplification arising from the self-consistent set of the Maxwell and relativistic quantum kinetic equations. It is shown a considerable increase in start-up and narrowing of the spectrum of the SASE power for amplifying X-ray frequencies compared with the classical SASE regime.

  3. Dynamo regimes and transitions in the VKS experiment

    CERN Document Server

    Berhanu, M; Boisson, J; Gallet, B; Gissinger, C; Fauve, S; Mordant, N; Pétrélis, F; Bourgoin, M; Odier, P; Pinton, J -F; Plihon, N; Aumaître, S; Chiffaudel, A; Daviaud, F; Dubrulle, B; Pirat, C

    2015-01-01

    The Von K{\\'a}rm{\\'a}n Sodium experiment yields a variety of dynamo regimes, when asymmetry is imparted to the flow by rotating impellers at different speed F1 and F2. We show that as the intensity of forcing, measured as F1 + F2, is increased, the transition to a self-sustained magnetic field is always observed via a supercritical bifurcation to a stationary state. For some values of the asymmetry parameter $\\\\theta$ = (F1--F2)/(F1+F2), time dependent dynamo regimes develop. They are observed either when the forcing is increased for a given value of asymmetry, or when the amount of asymmetry is varied at sufficiently high forcing. Two qualitatively different transitions between oscillatory and stationary regimes are reported, involving or not a strong divergence of the period of oscillations. These transitions can be interpreted using a low dimensional model based on the interactions of two dynamo modes.

  4. Challenges in Finding AGNs in the Low Luminosity Regime

    Science.gov (United States)

    Satyapal, Shobita; Abel, Nick; Secrest, Nathan; Singh, Amrit; Ellison, Sara

    2016-08-01

    Low luminosity AGNs are an important component of the AGN population. They are often found in the lowest mass galaxies or galaxies that lack classical bulges, a demographic that places important constraints to models of supermassive black hole seed formation and merger-free models of AGN fueling. The detection of AGNs in this low luminosity regime is challenging both because star formation in the host galaxy can dominate the optical spectrum and gas and dust can obscure the central engine at both optical and X-ray wavelengths. Thus while mid-infrared color selection and X-ray observations at energies <10 keV are often powerful tools in uncovering optically unidentified AGNs at higher luminosities, this is not the case in the low luminosity regime. In this talk, I will review the effectiveness of uncovering AGNs in the low luminosity regime using multiwavength investigations, with a focus on infrared spectroscopic signatures.

  5. Nonlinear-optical frequency-doubling metareflector: pulsed regime

    Science.gov (United States)

    Popov, A. K.; Myslivets, S. A.

    2016-01-01

    The properties of backward-wave second-harmonic metareflector operating in pulse regime are investigated. It is made of metamaterial which enables phase matching of contra-propagating fundamental and second-harmonic waves. References are given to the works that prove such a possibility. Physical principles underlying differences in the proposed and standard settings as well as between continuous-wave and pulsed regimes are discussed. Pulsed regime is more practicable and has a broader scope of applications. A set of partial differential equations which describe such a reflector with the account for losses are solved numerically. It is shown that unlike second-harmonic generation in standard settings, contra-propagating pulse of second harmonic may become much longer than the incident fundamental one and the difference grows with decrease in the input pulse length as compared to thickness of the metaslab. The revealed properties are important for applications and may manifest themselves beyond the optical wavelength range.

  6. Adelie penguin foraging location predicted by tidal regime switching.

    Directory of Open Access Journals (Sweden)

    Matthew J Oliver

    Full Text Available Penguin foraging and breeding success depend on broad-scale environmental and local-scale hydrographic features of their habitat. We investigated the effect of local tidal currents on a population of Adélie penguins on Humble Is., Antarctica. We used satellite-tagged penguins, an autonomous underwater vehicle, and historical tidal records to model of penguin foraging locations over ten seasons. The bearing of tidal currents did not oscillate daily, but rather between diurnal and semidiurnal tidal regimes. Adélie penguins foraging locations changed in response to tidal regime switching, and not to daily tidal patterns. The hydrography and foraging patterns of Adélie penguins during these switching tidal regimes suggest that they are responding to changing prey availability, as they are concentrated and dispersed in nearby Palmer Deep by variable tidal forcing on weekly timescales, providing a link between local currents and the ecology of this predator.

  7. The political constitution of the EU citizen rights regime

    DEFF Research Database (Denmark)

    Olsen, Tore Vincents

    2011-01-01

    Reactions to decisions by the European Court of Justice (ECJ) demonstrate that the political institutions in the Union should take responsibility for the development of the structure of the European Union's (EU) citizen rights regime. This article analyses different political views on the EU...... citizen rights regime. It argues that the disagreement between them is largely a disagreement between ‘reasonable views’. The disagreement is mainly based on different views about the levels (European, national) at which individuals are to be seen as equals and about the contribution of different...... communities and institutions to the good life of citizens, both individually and collectively. Taking the contestation between the different views seriously, the article argues in favour of political constitutionalism, according to which the development of the EU citizen rights regime is the responsibility...

  8. Modeling whistler wave generation regimes in magnetospheric cyclotron maser

    Directory of Open Access Journals (Sweden)

    D. L. Pasmanik

    2004-11-01

    Full Text Available Numerical analysis of the model for cyclotron instability in the Earth's magnetosphere is performed. This model, based on the self-consistent set of equations of quasi-linear plasma theory, describes different regimes of wave generation and related energetic particle precipitation. As the source of free energy the injection of energetic electrons with transverse anisotropic distribution function to the interaction region is considered. A parametric study of the model is performed. The main attention is paid to the analysis of generation regimes for different characteristics of energetic electron source, such as the shape of pitch angle distributions and its intensity. Two mechanisms of removal of energetic electrons from a generation region are considered, one is due to the particle precipitation through the loss cone and another one is related to the magnetic drift of energetic particles.

    It was confirmed that two main regimes occur in this system in the presence of a constant particle source, in the case of precipitation losses. At small source intensity relaxation oscillations were found, whose parameters are in good agreement with simplified analytical theory developed earlier. At a larger source intensity, transition to a periodic generation occurs. In the case of drift losses the regime of self-sustained periodic generation regime is realized for source intensity higher than some threshold. The dependencies of repetition period and dynamic spectrum shape on the source parameters were studied in detail. In addition to simple periodic regimes, those with more complex spectral forms were found. In particular, alteration of spikes with different spectral shape can take place. It was also shown that quasi-stationary generation at the low-frequency band can coexist with periodic modulation at higher frequencies.

    On the basis of the results obtained, the model for explanation of

  9. How will climate change modify river flow regimes in Europe?

    Directory of Open Access Journals (Sweden)

    C. Schneider

    2013-01-01

    Full Text Available Worldwide, flow regimes are being modified by various anthropogenic impacts and climate change induces an additional risk. Rising temperatures, declining snow cover and changing precipitation patterns will interact differently at different locations. Consequently, in distinct climate zones, unequal consequences can be expected in matters of water stress, flood risk, water quality, and food security. In particular, river ecosystems and their vital ecosystem services will be compromised as their species richness and composition have evolved over long time under natural flow conditions. This study aims at evaluating the exclusive impacts of climate change on river flow regimes in Europe. Various flow characteristics are taken into consideration and diverse dynamics are identified for each distinct climate zone in Europe. In order to simulate present-day natural flow regimes and future flow regimes under climate change, the global hydrology model WaterGAP3 is applied. All calculations for current and future conditions (2050s are carried out on a 5' × 5' European grid. To address uncertainty, bias-corrected climate forcing data of three different global climate models are used to drive WaterGAP3. Finally, the hydrological alterations of different flow characteristics are quantified by the Indicators of Hydrological Alteration approach. Results of our analysis indicate that on the European scale, climate change can be expected to modify flow regimes remarkably. This is especially the case in the Mediterranean (due to drier conditions with reduced precipitation across the year and in the boreal climate zone (due to reduced snowmelt, increased precipitation, and strong temperature rises. In the temperate climate zone, impacts increase from oceanic to continental. Regarding single flow characteristics, strongest impacts on timing were found for the boreal climate zone. This applies for both high and low flows. Flow magnitudes, in turn, will be

  10. Terahertz Quantum Plasmonics of Nanoslot Antennas in Nonlinear Regime.

    Science.gov (United States)

    Kim, Joon-Yeon; Kang, Bong Joo; Park, Joohyun; Bahk, Young-Mi; Kim, Won Tae; Rhie, Jiyeah; Jeon, Hyeongtag; Rotermund, Fabian; Kim, Dai-Sik

    2015-10-14

    Quantum tunneling in plasmonic nanostructures has presented an interesting aspect of incorporating quantum mechanics into classical optics. However, the study has been limited to the subnanometer gap regime. Here, we newly extend quantum plasmonics to gap widths well over 1 nm by taking advantage of the low-frequency terahertz regime. Enhanced electric fields of up to 5 V/nm induce tunneling of electrons in different arrays of ring-shaped nanoslot antennas of gap widths from 1.5 to 10 nm, which lead to a significant nonlinear transmission decrease. These observations are consistent with theoretical calculations considering terahertz-funneling-induced electron tunneling across the gap.

  11. Selection Criteria in Regime Switching Conditional Volatility Models

    Directory of Open Access Journals (Sweden)

    Thomas Chuffart

    2015-05-01

    Full Text Available A large number of nonlinear conditional heteroskedastic models have been proposed in the literature. Model selection is crucial to any statistical data analysis. In this article, we investigate whether the most commonly used selection criteria lead to choice of the right specification in a regime switching framework. We focus on two types of models: the Logistic Smooth Transition GARCH and the Markov-Switching GARCH models. Simulation experiments reveal that information criteria and loss functions can lead to misspecification ; BIC sometimes indicates the wrong regime switching framework. Depending on the Data Generating Process used in the experiments, great care is needed when choosing a criterion.

  12. Phase contrast and operation regimes in multifrequency atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Sergio [Departament de Disseny i Programació de Sistemes Electrònics, UPC—Universitat Politècnica de Catalunya Av. Bases, 61, 08242 Manresa (Barcelona) (Spain)

    2014-04-07

    In amplitude modulation atomic force microscopy the attractive and the repulsive force regimes induce phase shifts above and below 90°, respectively. In the more recent multifrequency approach, however, multiple operation regimes have been reported and the theory should be revisited. Here, a theory of phase contrast in multifrequency atomic force microscopy is developed and discussed in terms of energy transfer between modes, energy dissipation and the kinetic energy and energy transfer associated with externally driven harmonics. The single frequency virial that controls the phase shift might undergo transitions in sign while the average force (modal virial) remains positive (negative)

  13. Dynamic two state stochastic models for ecological regime shifts

    DEFF Research Database (Denmark)

    Møller, Jan Kloppenborg; Carstensen, Niels Jacob; Madsen, Henrik;

    2009-01-01

    of the model illustrates that hysteresis effect and regime shifts can be obtained for a limited range of parameter values only. The effect of multiplicative noise components entering at different levels of the model is presented and discussed. Including noise leads to very different results on the stability...... of regimes, depending on how the noise propagates through the system. The dynamical properties of a system should therefore be described through propagation of the state distributions rather than the state means and consequently, stochastic models should be compared in a probabilistic framework....

  14. PREDICTION OF FLOW REGIMES IN SPOUT-FLUIDIZED BEDS

    Institute of Scientific and Technical Information of China (English)

    Jiyu Zhang; Fengxiang Tang

    2006-01-01

    Five main flow regimes in spout-fluidized bed were identified in this study, namely, fixed bed, spout with aeration, spout-fluidization, jet in fluidized bed and slugging, together with their corresponding major frequencies translated from pressure signals. The empirical equation A=aBb, in which A=Fr* /(H/Di) and B=(Fr*/(H/D))/(μg/μmf) are respectively the spout-geometry and spout-geometry-fluidization dimensionless numbers, was proposed to distinguish these flow regimes.

  15. NAZI REGIME IN THE PERIODICAL A NOTÍ­CIA.

    Directory of Open Access Journals (Sweden)

    Bruna Luíza Barcellos

    2009-08-01

    Full Text Available The periodical A Notícia, of Joinville, city colonized for Germans, supported the nazi regime since the ascension of Adolf Hitler to the power. Between 1932 and 1944, some editions had printed the figure of Hitler and the nazi symbol, beyond dither messages to that regime. Based in the Análise de conteúdo (BARDIN, 1977, this article searchs to understand the representation made for the periodical A Notícia on this historical landmark, in other words, bring to the light the consequences of a part of occured world-wide history in catarinense territory.

  16. Development and current trends in the international nonproliferation regime

    International Nuclear Information System (INIS)

    The IAEA and its safeguards system is placed into a historical perspective. A personal perspective on the nonproliferation regime and on the Agency's role in it is then presented. This is done initially by discussing some of the landmark events in the history of the nonproliferation regime. Subsequently some of the history of arms control agreements and of the role of the IAEA are noted. Then political motivations of state and ways the Agency has an impact in the political nonproliferation sphere are addressed

  17. Measurement of flow in supercritical flow regime using cutthroat flumes

    Indian Academy of Sciences (India)

    Shrikant A Tekade; Avinash D Vasudeo; Aniruddha D Ghare; Ramesh N Ingle

    2016-02-01

    Cutthroat flume is commonly used for measurement of subcritical flow in open channel because of its simplicity and ease of construction. No experimental data is available in literature for measurement of flow in supercritical regime using cutthroat flume. The present paper finds the feasibility of cutthroat flume as a measurement device for flow in supercritical regime. Experimental data are generated to develop the relation between discharge and observed head at a specified location on upstream of throat section. Regression analysis for discharge and head indicated a good correlation. Based on all the experimental data generated, a relationship between discharge and head is proposed.

  18. Explicit Mapping of Acoustic Regimes For Wind Instruments

    CERN Document Server

    Missoum, Samy; Doc, Jean-Baptiste

    2014-01-01

    This paper proposes a methodology to map the various acoustic regimes of wind instruments. The maps can be generated in a multi-dimensional space consisting of design, control parameters, and initial conditions. The bound- aries of the maps are obtained explicitly in terms of the parameters using a support vector machine (SVM) classifier as well as a dedicated adaptive sam- pling scheme. The approach is demonstrated on a simplified clarinet model for which several maps are generated based on different criteria. Examples of computation of the probability of occurrence of a specific acoustic regime are also provided. In addition, the approach is demonstrated on a design optimization example for optimal intonation.

  19. Using Clustering to Establish Climate Regimes from PCM Output

    Science.gov (United States)

    Oglesby, Robert; Arnold, James E. (Technical Monitor); Hoffman, Forrest; Hargrove, W. W.; Erickson, D.

    2002-01-01

    A multivariate statistical clustering technique--based on the k-means algorithm of Hartigan has been used to extract patterns of climatological significance from 200 years of general circulation model (GCM) output. Originally developed and implemented on a Beowulf-style parallel computer constructed by Hoffman and Hargrove from surplus commodity desktop PCs, the high performance parallel clustering algorithm was previously applied to the derivation of ecoregions from map stacks of 9 and 25 geophysical conditions or variables for the conterminous U.S. at a resolution of 1 sq km. Now applied both across space and through time, the clustering technique yields temporally-varying climate regimes predicted by transient runs of the Parallel Climate Model (PCM). Using a business-as-usual (BAU) scenario and clustering four fields of significance to the global water cycle (surface temperature, precipitation, soil moisture, and snow depth) from 1871 through 2098, the authors' analysis shows an increase in spatial area occupied by the cluster or climate regime which typifies desert regions (i.e., an increase in desertification) and a decrease in the spatial area occupied by the climate regime typifying winter-time high latitude perma-frost regions. The patterns of cluster changes have been analyzed to understand the predicted variability in the water cycle on global and continental scales. In addition, representative climate regimes were determined by taking three 10-year averages of the fields 100 years apart for northern hemisphere winter (December, January, and February) and summer (June, July, and August). The result is global maps of typical seasonal climate regimes for 100 years in the past, for the present, and for 100 years into the future. Using three-dimensional data or phase space representations of these climate regimes (i.e., the cluster centroids), the authors demonstrate the portion of this phase space occupied by the land surface at all points in space and time

  20. Using Clustering to Establish Climate Regimes from PCM Output

    Science.gov (United States)

    Hoffman, F.; Oglesby, R.; Hargrove, W. W.; Erickson, D.

    2002-12-01

    A multivariate statistical clustering technique--based on the k-means algorithm of Hartigan--has been used to extract patterns of climatological significance from 200 years of general circulation model (GCM) output. Originally developed and implemented on a Beowulf-style parallel computer constructed by Hoffman and Hargrove from surplus commodity desktop PCs, the high performance parallel clustering algorithm was previously applied to the derivation of ecoregions from map stacks of 9 and 25 geophysical conditions or variables for the conterminous U.S. at a resolution of 1 sq km. Now applied both across space and through time, the clustering technique yields temporally-varying climate regimes predicted by transient runs of the Parallel Climate Model (PCM). Using a business-as-usual (BAU) scenario and clustering four fields of significance to the global water cycle (surface temperature, precipitation, soil moisture, and snow depth) from 1871 through 2098, the authors' analysis shows an increase in spatial area occupied by the cluster or climate regime which typifies desert regions (i.e., an increase in desertification) and a decrease in the spatial area occupied by the climate regime typifying winter-time high latitude perma-frost regions. The patterns of cluster changes have been analyzed to understand the predicted variability in the water cycle on global and continental scales. In addition, representative climate regimes were determined by taking three 10-year averages of the fields 100 years apart for northern hemisphere winter (December, January, and February) and summer (June, July, and August). The result is global maps of typical seasonal climate regimes for 100 years in the past, for the present, and for 100 years into the future. Using three-dimensional data or phase space representations of these climate regimes (i.e., the cluster centroids), the authors demonstrate the portion of this phase space occupied by the land surface at all points in space and

  1. Predicting weather regime transitions in Northern Hemisphere datasets

    Energy Technology Data Exchange (ETDEWEB)

    Kondrashov, D. [University of California, Department of Atmospheric and Oceanic Sciences and Institute of Geophysics and Planetary Physics, Los Angeles, CA (United States); Shen, J. [UCLA, Department of Statistics, Los Angeles, CA (United States); Berk, R. [UCLA, Department of Statistics, Los Angeles, CA (United States); University of Pennsylvania, Department of Criminology, Philadelphia, PA (United States); D' Andrea, F.; Ghil, M. [Ecole Normale Superieure, Departement Terre-Atmosphere-Ocean and Laboratoire de Meteorologie Dynamique (CNRS and IPSL), Paris Cedex 05 (France)

    2007-10-15

    A statistical learning method called random forests is applied to the prediction of transitions between weather regimes of wintertime Northern Hemisphere (NH) atmospheric low-frequency variability. A dataset composed of 55 winters of NH 700-mb geopotential height anomalies is used in the present study. A mixture model finds that the three Gaussian components that were statistically significant in earlier work are robust; they are the Pacific-North American (PNA) regime, its approximate reverse (the reverse PNA, or RNA), and the blocked phase of the North Atlantic Oscillation (BNAO). The most significant and robust transitions in the Markov chain generated by these regimes are PNA {yields} BNAO, PNA {yields} RNA and BNAO {yields} PNA. The break of a regime and subsequent onset of another one is forecast for these three transitions. Taking the relative costs of false positives and false negatives into account, the random-forests method shows useful forecasting skill. The calculations are carried out in the phase space spanned by a few leading empirical orthogonal functions of dataset variability. Plots of estimated response functions to a given predictor confirm the crucial influence of the exit angle on a preferred transition path. This result points to the dynamic origin of the transitions. (orig.)

  2. Is the Economic Crisis Challenging the Prevailing Gender Regime?

    DEFF Research Database (Denmark)

    Leschke, Janine; Jepsen, Maria

    2014-01-01

    This paper addresses the question of whether the current economic and financial crisis is challenging the prevailing gender-equality model in four European countries: Denmark, Germany, Slovakia, and the United Kingdom. After situating the countries in relation to the underlying gender regime...

  3. Detection and Assessment of Ecosystem Regime Shifts from Fisher Information

    Directory of Open Access Journals (Sweden)

    B. Roy Frieden

    2008-06-01

    Full Text Available Ecosystem regime shifts, which are long-term system reorganizations, have profound implications for sustainability. There is a great need for indicators of regime shifts, particularly methods that are applicable to data from real systems. We have developed a form of Fisher information that measures dynamic order in complex systems. Here we propose the use of Fisher information as a means of: (1 detecting dynamic regime shifts in ecosystems, and (2 assessing the quality of the shift in terms of intensity and pervasiveness. Intensity is reflected by the degree of change in dynamic order, as determined by Fisher information, and pervasiveness is a reflection of how many observable variables are affected by the change. We present a new robust methodology to calculate Fisher information from time series field data. We demonstrate the use of Fisher information to detect regime shifts on a model for a shallow lake. Next, we use Fisher information to analyze marine ecosystem response to physical changes using real time-series data of a coastal marine ecosystem, the North Pacific Ocean.

  4. Exploiting synergies between nonproliferation verification regimes: A pragmatic approach

    International Nuclear Information System (INIS)

    This paper considers the potential for expanding interaction and exploiting synergies between different multilateral disarmament and nonproliferation regimes. It concludes that although there are political barriers to high-level and pervasive synergization, there are opportunities for pragmatic, functional steps to be taken as a way of building confidence and experience. (author)

  5. Dynamic Financial Constraints: Distinguishing Mechanism Design from Exogenously Incomplete Regimes.

    Science.gov (United States)

    Karaivanov, Alexander; Townsend, Robert M

    2014-05-01

    We formulate and solve a range of dynamic models of constrained credit/insurance that allow for moral hazard and limited commitment. We compare them to full insurance and exogenously incomplete financial regimes (autarky, saving only, borrowing and lending in a single asset). We develop computational methods based on mechanism design, linear programming, and maximum likelihood to estimate, compare, and statistically test these alternative dynamic models with financial/information constraints. Our methods can use both cross-sectional and panel data and allow for measurement error and unobserved heterogeneity. We estimate the models using data on Thai households running small businesses from two separate samples. We find that in the rural sample, the exogenously incomplete saving only and borrowing regimes provide the best fit using data on consumption, business assets, investment, and income. Family and other networks help consumption smoothing there, as in a moral hazard constrained regime. In contrast, in urban areas, we find mechanism design financial/information regimes that are decidedly less constrained, with the moral hazard model fitting best combined business and consumption data. We perform numerous robustness checks in both the Thai data and in Monte Carlo simulations and compare our maximum likelihood criterion with results from other metrics and data not used in the estimation. A prototypical counterfactual policy evaluation exercise using the estimation results is also featured.

  6. Just for Fun? The Emotional Regime of Experiential Consumption

    DEFF Research Database (Denmark)

    Jantzen, Christian; Fitchett, James; Østergaard, Per;

    2012-01-01

    Experiential consumption emphasizes emotional and hedonic qualities in the marketplace stressing the importance of experiences for ‘the good life’ and positioning consumption as a legitimate way to generate interesting and relevant experiences. The concept of emotional regimes (Reddy, 2001) is used...

  7. Process-based humidity control regime for greenhouse crops

    NARCIS (Netherlands)

    Korner, O.; Challa, H.

    2003-01-01

    Modern greenhouses in The Netherlands are designed for efficient use of energy. Climate control traditionally aims at optimal crop performance. However, energy saving is a major issue for the development of new temperature regimes. Temperature integration (TI) results in fluctuating and often high r

  8. Operating regimes of signaling cycles: statics, dynamics, and noise filtering.

    Directory of Open Access Journals (Sweden)

    Carlos Gomez-Uribe

    2007-12-01

    Full Text Available A ubiquitous building block of signaling pathways is a cycle of covalent modification (e.g., phosphorylation and dephosphorylation in MAPK cascades. Our paper explores the kind of information processing and filtering that can be accomplished by this simple biochemical circuit. Signaling cycles are particularly known for exhibiting a highly sigmoidal (ultrasensitive input-output characteristic in a certain steady-state regime. Here, we systematically study the cycle's steady-state behavior and its response to time-varying stimuli. We demonstrate that the cycle can actually operate in four different regimes, each with its specific input-output characteristics. These results are obtained using the total quasi-steady-state approximation, which is more generally valid than the typically used Michaelis-Menten approximation for enzymatic reactions. We invoke experimental data that suggest the possibility of signaling cycles operating in one of the new regimes. We then consider the cycle's dynamic behavior, which has so far been relatively neglected. We demonstrate that the intrinsic architecture of the cycles makes them act--in all four regimes--as tunable low-pass filters, filtering out high-frequency fluctuations or noise in signals and environmental cues. Moreover, the cutoff frequency can be adjusted by the cell. Numerical simulations show that our analytical results hold well even for noise of large amplitude. We suggest that noise filtering and tunability make signaling cycles versatile components of more elaborate cell-signaling pathways.

  9. Accessing Imagined Communities and Reinscribing Regimes of Truth

    Science.gov (United States)

    Carroll, Sherrie; Motha, Suhanthie; Price, Jeremy N.

    2008-01-01

    In this article, we explore the complex and nebulous terrain between two theoretical concepts, imagined communities (Norton, 2000, 2001), that is, individuals' imagined affiliations with certain groups, and regimes of truth (Foucault, 1980), dominant images inscribed and reinscribed into individual consciousness until they become normative. Using…

  10. Regimes of flow induced vibration for tandem, tethered cylinders

    Science.gov (United States)

    Nave, Gary; Stremler, Mark

    2015-11-01

    In the wake of a bluff body, there are a number of dynamic response regimes that exist for a trailing bluff body depending on spacing, structural restoring forces, and the mass-damping parameter m* ζ . For tandem cylinders with low values of m* ζ , two such regimes of motion are Gap Flow Switching and Wake Induced Vibration. In this study, we consider the dynamics of a single degree-of-freedom rigid cylinder in the wake of another in these regimes for a variety of center-to-center cylinder spacings (3-5 diameters) and Reynolds numbers (4,000-11,000). The system consists of a trailing cylinder constrained to a circular arc around a fixed leading cylinder, which, for small angle displacements, bears a close resemblance to the transversely oscillating cylinders found more commonly in existing literature. From experiments on this system, we compare and contrast the dynamic response within these two regimes. Our results show sustained oscillations in the absence of a structural restoring force in all cases, providing experimental support for the wake stiffness assumption, which is based on the mean lift toward the center line of flow.

  11. Exploring the epsilon regime with twisted mass fermions

    CERN Document Server

    Jansen, K; Shindler, A; Urbach, C; Wenger, U

    2007-01-01

    In this proceeding contribution we report on a first study in order to explore the so called epsilon regime with Wilson twisted mass (Wtm) fermions. To show the potential of this approach we give a preliminary determination of the chiral condensate.

  12. Dynamic Financial Constraints: Distinguishing Mechanism Design from Exogenously Incomplete Regimes.

    Science.gov (United States)

    Karaivanov, Alexander; Townsend, Robert M

    2014-05-01

    We formulate and solve a range of dynamic models of constrained credit/insurance that allow for moral hazard and limited commitment. We compare them to full insurance and exogenously incomplete financial regimes (autarky, saving only, borrowing and lending in a single asset). We develop computational methods based on mechanism design, linear programming, and maximum likelihood to estimate, compare, and statistically test these alternative dynamic models with financial/information constraints. Our methods can use both cross-sectional and panel data and allow for measurement error and unobserved heterogeneity. We estimate the models using data on Thai households running small businesses from two separate samples. We find that in the rural sample, the exogenously incomplete saving only and borrowing regimes provide the best fit using data on consumption, business assets, investment, and income. Family and other networks help consumption smoothing there, as in a moral hazard constrained regime. In contrast, in urban areas, we find mechanism design financial/information regimes that are decidedly less constrained, with the moral hazard model fitting best combined business and consumption data. We perform numerous robustness checks in both the Thai data and in Monte Carlo simulations and compare our maximum likelihood criterion with results from other metrics and data not used in the estimation. A prototypical counterfactual policy evaluation exercise using the estimation results is also featured. PMID:25246710

  13. Dynamic Financial Constraints: Distinguishing Mechanism Design from Exogenously Incomplete Regimes*

    Science.gov (United States)

    Karaivanov, Alexander; Townsend, Robert M.

    2014-01-01

    We formulate and solve a range of dynamic models of constrained credit/insurance that allow for moral hazard and limited commitment. We compare them to full insurance and exogenously incomplete financial regimes (autarky, saving only, borrowing and lending in a single asset). We develop computational methods based on mechanism design, linear programming, and maximum likelihood to estimate, compare, and statistically test these alternative dynamic models with financial/information constraints. Our methods can use both cross-sectional and panel data and allow for measurement error and unobserved heterogeneity. We estimate the models using data on Thai households running small businesses from two separate samples. We find that in the rural sample, the exogenously incomplete saving only and borrowing regimes provide the best fit using data on consumption, business assets, investment, and income. Family and other networks help consumption smoothing there, as in a moral hazard constrained regime. In contrast, in urban areas, we find mechanism design financial/information regimes that are decidedly less constrained, with the moral hazard model fitting best combined business and consumption data. We perform numerous robustness checks in both the Thai data and in Monte Carlo simulations and compare our maximum likelihood criterion with results from other metrics and data not used in the estimation. A prototypical counterfactual policy evaluation exercise using the estimation results is also featured. PMID:25246710

  14. Political Regime and Human Capital: A Cross-Country Analysis

    Science.gov (United States)

    Klomp, Jeroen; de Haan, Jakob

    2013-01-01

    We examine the relationship between different dimensions of the political regime in place and human capital using a two-step structural equation model. In the first step, we employ factor analysis on 16 human capital indicators to construct two new human capital measures (basic and advanced human capital). In the second step, we estimate the…

  15. Political regime and human capital : A cross-country analysis

    NARCIS (Netherlands)

    Klomp, J.G.; de Haan, J.

    2013-01-01

    We examine the relationship between different dimensions of the political regime in place and human capital using a two-step structural equation model. In the first step, we employ factor analysis on 16 human capital indicators to construct two new human capital measures (basic and advanced human ca

  16. Political regime and human capital: A cross-country analysis

    NARCIS (Netherlands)

    Klomp, J.G.; Haan, de J.

    2013-01-01

    We examine the relationship between different dimensions of the political regime in place and human capital using a two-step structural equation model. In the first step, we employ factor analysis on 16 human capital indicators to construct two new human capital measures (basic and advanced human ca

  17. Syria: The Consolidation of the Asad Regime, 1970-1975.

    Science.gov (United States)

    Olson, Robert W.

    1982-01-01

    Up to 1975-76, Syria's Hafiz al-Asad was successful in consolidating his power, securing the maintenance of his regime, and broadening his base of political power. His system started weakening in 1975 due to increased opposition stemming from Syria's intervention in the Lebanese civil war. (AM)

  18. Shearing box simulations in the Rayleigh unstable regime

    DEFF Research Database (Denmark)

    Nauman, Farrukh; Blackman, Eric G.

    2015-01-01

    We study the stability properties of Rayleigh unstable flows both in the purely hydrodynamic and magnetohydrodynamic (MHD) regimes for two different values of the shear $q=2.1, 4.2$ ($q = - d\\ln\\Omega / d\\ln r$) and compare it with the Keplerian case $q=1.5$. The Rayleigh stability criterion states...

  19. Welfare Attitudes and Social Expenditure: Do Regimes Shape Public Opinion?

    Science.gov (United States)

    Jakobsen, Tor Georg

    2011-01-01

    This article examines the link between regime types, social expenditure, and welfare attitudes. By employing data on 19 countries taken from the World Values Survey, the main aim is to see to what degree the institutions of a country affect the attitudes of its citizens. According to Esping-Andersen ("The three worlds of welfare capitalism".…

  20. Alternative pricing regimes in Ontario : exploring the impacts

    International Nuclear Information System (INIS)

    Legislative goals were recently established in Ontario to promote reliability and quality of electricity service and to ensure that distribution rates for customers remain reasonable. This presentation explored the effect of changing electricity pricing structures on residential customers in Ontario. This study investigated a period between May to December 2005, in the town of Milton, Ontario. Monthly demand was measured for each month, and monthly weighted averages were presented. Residents with electric heating were removed from the sample. Four pricing structure scenarios were examined: (1) flat rates; (2) time-of-use pricing regimes; (3) real time pricing regimes; and (4) critical peak pricing. Average monthly consumption rates for July and August for all 4 scenarios were presented. Results for time-of-use were compared to flat rates, which showed a slight increase in monthly costs. Real time average monthly electricity costs were significantly higher. Time-of-use costs increased by 57 per cent during the periods examined. Real time pricing regimes resulted in a 196 per cent rise in costs. It was concluded that more research must be done to explore the policy implications of pricing regimes and their effect on consumer behaviour. refs., tabs., figs

  1. Towards an Orderly Exit Regime in English Higher Education

    Science.gov (United States)

    Fisher, Andrew

    2016-01-01

    In a competitive market, the exit of those suppliers who cannot offer an attractive product at an attractive price is seen as desirable. However, the consequences for consumers when their own supplier leaves the market in an unplanned or disorderly way may be undesirable. Exit regimes exist in regulated markets to ensure that consumers are not…

  2. Oil and gas fiscal regimes of the western Canadian provinces

    International Nuclear Information System (INIS)

    This report compares the fiscal regimes in British Columbia, Alberta, Saskatchewan and Manitoba. During 1985-1988, federal and provincial governments have made numerous fiscal changes, many in response to the drop in world oil prices. The new fiscal policies generally have reflected governments' willingness to forego revenues in an effort to aid the oil and gas industry, with certain exemptions. Since 1988, changes have reflected trends of consolidation and less government willingness to forego revenues. A federal large corporations capital tax has been introduced, the natural gas exploration holiday in Alberta expired, new oil royalties were introduced, and changes were made in fiscal regimes to accomodate horizontal drilling in Saskatchewan and Manitoba. In this document, the existing corporate tax regime is described. A comparison of fiscal regimes must recognize the differing scale and nature of oil and gas operations among the 4 provinces, with Alberta accounting for 80-90% of Canada's oil and gas productions, while British Columbia, Saskatchewan and Manitoba are much smaller producers. The document describes Crown royalties and incentives and freehold taxes for each type of fuel (crude oil, natural gas, natural gas byproducts, nonconventional oil). 8 figs

  3. Nonlinear regimes in mean-field full-sphere dynamo

    CERN Document Server

    Pipin, V V

    2016-01-01

    The mean-field dynamo model is employed to study the non-linear dynamo regimes in a fully convective star of mass 0.3$M_{\\odot}$ rotating with period of 10 days. The differential rotation law was estimated using the mean-field hydrodynamic and heat transport equations. For the intermediate parameter of the turbulent magnetic Reynolds number, $Pm_{T}=3$ we found the oscillating dynamo regimes with period about 40Yr. The higher $Pm_{T}$ results to longer dynamo periods. The meridional circulation has one cell per hemisphere. It is counter-clockwise in the Northen hemisphere. The amplitude of the flow at the surface around 1 m/s. Tne models with regards for meridional circulation show the anti-symmetric relative to equator magnetic field. If the large-scale flows is fixed we find that the dynamo transits from axisymmetric to non-axisymmetric regimes for the overcritical parameter of the $\\alpha$effect. The change of dynamo regime occurs because of the non-axisymmetric non-linear $\\alpha$-effect. The situation pe...

  4. Microgravity Flow Regime Data: Buoyancy and Mixing Apparatus Effects

    Science.gov (United States)

    Shephard, Adam; Best, Frederick

    2010-01-01

    Zero-g two-phase flow data set qualification and flight experiment design have not been standardized and as a result, agreement among researchers has not been reached regarding what experimental conditions adequately approximate those of microgravity. The effects of buoyancy forces and mixing apparatus on the flow regime transitions are presented in this study. The gravity conditions onboard zero-g aircraft are at best 10-3 g which is used to approximate the 10-5 g conditions of microgravity, thus the buoyancy forces present on zero-g aircraft can become significantly large and unrepresentative of microgravity. When buoyancy forces approach those of surface tension forces, buoyancy induced coalescence occurs. When discussing flow regime transitions, these large buoyancy forces lead to flow regime transitions which otherwise would not occur. The buoyancy attributes of the two-phase flow data sets available in the literature are evaluated to determine which data sets exhibit buoyancy induced transitions. Upon comparison of the representative data sets, the affects of different mixing apparatus can be seen in the superficial velocity flow regime maps.

  5. Sputtering of Ge(001): transition between dynamic scaling regimes

    DEFF Research Database (Denmark)

    Smilgies, D.-M.; Eng, P.J.; Landemark, E.;

    1997-01-01

    We have studied the dynamic behavior of the Ge(001) surface during sputtering in situ and in real time using synchrotron X-ray diffraction. We find two dynamic regimes as a function of surface temperature and sputter current which are separated by a sharp transition. The boundary between these two...

  6. Search Regimes and the Industrial Dynamics of Science

    Science.gov (United States)

    Bonaccorsi, Andrea

    2008-01-01

    The article addresses the issue of dynamics of science, in particular of new sciences born in twentieth century and developed after the Second World War (information science, materials science, life science). The article develops the notion of search regime as an abstract characterization of dynamic patterns, based on three dimensions: the rate of…

  7. Regime shifts limit the predictability of land-system change

    DEFF Research Database (Denmark)

    Müller, Daniel; Sun, Zhanli; Vongvisouk, Thoumthone;

    2014-01-01

    (China, Laos, Vietnam and Indonesia). The results show how sudden events and gradual changes in underlying drivers caused rapid, surprising and widespread land-system changes, including shifts to different regimes in China, Vietnam and Indonesia, whereas land systems in Laos remained stable in the study...

  8. Globalisation, the "Idea of a University" and Its Ethical Regimes

    Science.gov (United States)

    Marginson, Simon

    2007-01-01

    This paper sketches the impact of globalisation and internationalisation on the terrain of values and ethics in higher education. The first part of the paper discusses values and ethics in higher education in relation to the "Idea of a University", and identifies the ethical regimes essential to the functioning of HEIs as knowledge-forming…

  9. Morphodynamic regime and long-term evolution of meandering rivers

    Science.gov (United States)

    Frascati, Alessandro; Lanzoni, Stefano

    2009-06-01

    In the present contribution we focus our attention on the long-term behavior of meandering rivers, a very common pattern in nature. This class of dynamical systems is driven by the coexistence of various intrinsically nonlinear mechanisms which determine the possible occurrence of two different morphodynamic regimes: the subresonant and the superresonant regimes. Investigating the full range of morphodynamic conditions, we objectively compare the morphologic characteristics exhibited by synthetically generated and observed planimetric patterns. The analysis is carried out examining, through principal component analysis, a suitable set of morphological variables. We show that even in the presence of the strong filtering action exerted by cutoff processes, a closer, although not yet complete, similarity with natural meandering planforms can be achieved only by adopting a flow field model which accounts for the full range of morphodynamic regimes. We also introduce a new morphodynamic length scale, ?m, associated with spatially oscillating disturbances. Once normalized with this length scale, the relevant morphologic features of the simulated long-term patterns (e.g., the probability density function of local curvature and the geometric characteristics of oxbow lakes) tend to collapse on two distinct behaviors, depending on the dominant morphologic regime.

  10. Analysis of the Two-Regime Method on Square Meshes

    KAUST Repository

    Flegg, Mark B.

    2014-01-01

    The two-regime method (TRM) has been recently developed for optimizing stochastic reaction-diffusion simulations [M. Flegg, J. Chapman, and R. Erban, J. Roy. Soc. Interface, 9 (2012), pp. 859-868]. It is a multiscale (hybrid) algorithm which uses stochastic reaction-diffusion models with different levels of detail in different parts of the computational domain. The coupling condition on the interface between different modeling regimes of the TRM was previously derived for onedimensional models. In this paper, the TRM is generalized to higher dimensional reaction-diffusion systems. Coupling Brownian dynamics models with compartment-based models on regular (square) two-dimensional lattices is studied in detail. In this case, the interface between different modeling regimes contains either flat parts or right-angle corners. Both cases are studied in the paper. For flat interfaces, it is shown that the one-dimensional theory can be used along the line perpendicular to the TRM interface. In the direction tangential to the interface, two choices of the TRM parameters are presented. Their applicability depends on the compartment size and the time step used in the molecular-based regime. The two-dimensional generalization of the TRM is also discussed in the case of corners. © 2014 Society for Industrial and Applied Mathematics.

  11. The perturbative Regge-calculus regime of loop quantum gravity

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, Eugenio [Scuola Normale Superiore and INFN Pisa, Piazza dei Cavalieri 7, I-56126 Pisa (Italy)], E-mail: e.bianchi@sns.it; Modesto, Leonardo [Department of Physics, Bologna University and INFN Bologna, V. Irnerio 46, I-40126 Bologna (Italy); Centre de Physique Theorique de Luminy, Universite de la Mediterranee, F-13288 Marseille (France)], E-mail: modesto@bo.infn.it

    2008-06-21

    The relation between loop quantum gravity and Regge calculus has been pointed out many times in the literature. In particular the large spin asymptotics of the Barrett-Crane vertex amplitude is known to be related to the Regge action. In this paper we study a semiclassical regime of loop quantum gravity and show that it admits an effective description in terms of perturbative area-Regge-calculus. The regime of interest is identified by a class of states given by superpositions of four-valent spin networks, peaked on large spins. As a probe of the dynamics in this regime, we compute explicitly two- and three-area correlation functions at the vertex amplitude level. We find that they match with the ones computed perturbatively in area-Regge-calculus with a single 4-simplex, once a specific perturbative action and measure have been chosen in the Regge-calculus path integral. Correlations of other geometric operators and the existence of this regime for other models for the dynamics are briefly discussed.

  12. Second regime tokamak operation at large aspect ratio

    International Nuclear Information System (INIS)

    The equilibrium, stability, and transport properties of large aspect ratio tokamaks operating at the second stability regime are described theoretically using numerical and analytical techniques. It has been shown that, at large aspect ratio, significant current profile control is possible with relatively modest amounts of neutral beam current drive, and the power needed to access and maintain the second regime operation is calculated to be about 3 MW using the results of an integrated 1.5D transport and stability code. An example second regime experiment has been described and the results are presented of extensive calculations illustrating several possible operating scenarios, external and internal model stability boundaries, and the experimental features needed to evaluate and test the high beta tokamak theories. The theory which describes the stabilizing effect of energetic particles during high beta operation was extended to finite aspect ratio. A key technical problem for application of this technique appears to be caused by ripple transport. Plasma rotation effects are found to be generally destabilizing and several other schemes for improved access to the second stability regime are discussed including ponderomotive stabilization of the plasma edge region and active feedback control

  13. Learning, competency nomads, and post-signifying regimes

    DEFF Research Database (Denmark)

    Krejsler, John

    2007-01-01

    of these changes as a transition from ‘industrial' to ‘knowledge society'; this is done by re-describing this transition from within as a transition from ‘signifying' to ‘post-signifying' regimes. From this conceptual experiment the ‘competency nomad' emerges as a powerful concept that seems useful to replace...

  14. Perfect photon absorption in nonlinear regime of cavity quantum electrodynamics

    CERN Document Server

    Agarwal, G S; Wang, Liyong; Zhu, Yifu

    2016-01-01

    It has been shown that perfect photon absorption can occur in the linear excitation regime of cavity quantum electrodynamics (CQED), in which photons from two identical light fields coupled into two ends of the cavity are completely absorbed and result in excitation of the polariton state of the CQED system. The output light from the cavity is totally suppressed by the destructive interference and the polariton state can only decay incoherently back to the ground state. Here we analyze the perfect photon absorption and onset of optical bistability in the nonlinear regime of the CQED and show that the perfect photon absorption persists in the nonlinear regime of the CQED below the threshold of the optical bistability. Therefore the perfect photon absorption is a phenomenon that can be observed in both linear and nonlinear regimes of CQED. Furthermore, our study reveals for the first time that the optical bistability is influenced by the input-light interference and can be manipulated by varying the relative ph...

  15. Primordial black holes in linear and non-linear regimes

    CERN Document Server

    Allahyari, Alireza; Abolhasani, Ali Akbar

    2016-01-01

    Using the concept of apparent horizon for dynamical black holes, we revisit the formation of primordial black holes (PBH) in the early universe for both linear and non-linear regimes. First, we develop the perturbation theory for spherically symmetric spacetimes to study the formation of spherical PBHs in linear regime and we fix two gauges. We also introduce a well defined gauge invariant quantity for the expansion. Using this quantity, we argue that PBHs do not form in the linear regime. Finally, we study the non-linear regime. We adopt the spherical collapse picture by taking a closed FRW model in the radiation dominated era to investigate PBH formation. Taking the initial condition of the spherical collapse from the linear theory of perturbations, we allow for both density and velocity perturbations. Our model gives a constraint on the velocity perturbation. This model also predicts that the apparent horizon of PBHs forms when $\\delta > 3$. Applying the sound horizon constraint, we have shown the threshol...

  16. Regime-switching models to study psychological process

    NARCIS (Netherlands)

    Hamaker, E.L.; Grasman, R.P.P.P.; Kamphuis, J.H.

    2010-01-01

    Many psychological processes are characterized by recurrent shifts between different states. To model these processes at the level of the individual, regime-switching models may prove useful. In this chapter we discuss two of these models: the threshold autoregressive model and the Markov switching

  17. The human dimension of fire regimes on Earth

    Science.gov (United States)

    Bowman, David M.J.S.; Balch, Jennifer; Artaxo, Paulo; Bond, William J.; Cochrane, Mark A.; D'Antonio, Carla M.; DeFries, Ruth; Johnston, Fay H.; Keeley, Jon E.; Krawchuk, Meg A.; Kull, Christian A.; Michelle, Mack; Moritz, Max A.; Pyne, Stephen; Roos, Christopher I.; Scott, Andrew C.; Sodhi, Navjot S.; Swetnam, Thomas W.

    2011-01-01

    Humans and their ancestors are unique in being a fire-making species, but 'natural' (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human-set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from 'natural' background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changes and loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke-related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas-induced warming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding

  18. The human dimension of fire regimes on Earth.

    Science.gov (United States)

    Bowman, David M J S; Balch, Jennifer; Artaxo, Paulo; Bond, William J; Cochrane, Mark A; D'Antonio, Carla M; Defries, Ruth; Johnston, Fay H; Keeley, Jon E; Krawchuk, Meg A; Kull, Christian A; Mack, Michelle; Moritz, Max A; Pyne, Stephen; Roos, Christopher I; Scott, Andrew C; Sodhi, Navjot S; Swetnam, Thomas W; Whittaker, Robert

    2011-12-01

    Humans and their ancestors are unique in being a fire-making species, but 'natural' (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human-set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from 'natural' background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changes and loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke-related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas-induced warming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding

  19. Climate change and future fire regimes: Examples from California

    Science.gov (United States)

    Keeley, Jon E.; Syphard, Alexandra D.

    2016-01-01

    Climate and weather have long been noted as playing key roles in wildfire activity, and global warming is expected to exacerbate fire impacts on natural and urban ecosystems. Predicting future fire regimes requires an understanding of how temperature and precipitation interact to control fire activity. Inevitably this requires historical analyses that relate annual burning to climate variation. Fuel structure plays a critical role in determining which climatic parameters are most influential on fire activity, and here, by focusing on the diversity of ecosystems in California, we illustrate some principles that need to be recognized in predicting future fire regimes. Spatial scale of analysis is important in that large heterogeneous landscapes may not fully capture accurate relationships between climate and fires. Within climatically homogeneous subregions, montane forested landscapes show strong relationships between annual fluctuations in temperature and precipitation with area burned; however, this is strongly seasonal dependent; e.g., winter temperatures have very little or no effect but spring and summer temperatures are critical. Climate models that predict future seasonal temperature changes are needed to improve fire regime projections. Climate does not appear to be a major determinant of fire activity on all landscapes. Lower elevations and lower latitudes show little or no increase in fire activity with hotter and drier conditions. On these landscapes climate is not usually limiting to fires but these vegetation types are ignition-limited. Moreover, because they are closely juxtaposed with human habitations, fire regimes are more strongly controlled by other direct anthropogenic impacts. Predicting future fire regimes is not rocket science; it is far more complicated than that. Climate change is not relevant to some landscapes, but where climate is relevant, the relationship will change due to direct climate effects on vegetation trajectories, as well as

  20. Early warning of atmospheric regime transitions using transfer operators

    Science.gov (United States)

    Tantet, Alexis; Dijkstra, Henk

    2015-04-01

    The existence of persistent midlatitude atmospheric regimes, such as blocking events, with time scales larger than 5-10 days and indications of preferred transition paths between them motivates the development of early-warning indicators of regime transitions. Here, we use a barotropic model of the northern midlatitudes winter flow to study such meta-stable regimes. We look at estimates of transfer operators acting on densities evolving on a reduced phase space spanned by the first Empirical Orthogonal Functions of the streamfunction and develop an early-warning indicator of zonal to blocked flow transition. The study of the spectra of transfer operators estimated for different lags reveals a multi-level structure in the flow as well as the effect of memory on the reduced dynamics due to past interactions between the resolved and unresolved variables. The slowest motions in the reduced phase space are thereby found to have time scales larger than 8 days and to behave as Markovian for larger lags. These motions are associated with meta-stable regimes and their transitions and can be detected as almost-invariant sets of the transfer operator. The early-warning indicator is based on the action on an initial density of products of the transfer operators estimated for sufficiently long lags, making use of the semi-group property of these operators and shows relatively good Peirce skill score. From the energy budget of the model, we are able to explain the meta-stability of the regimes and the existence of preferred transition paths as the manifestation of barotropic instability. Finally, even though the model is highly simplified, the skill of the early warning indicator is promising, suggesting that the transfer operator approach can be used in parallel to an operational deterministic model for stochastic prediction or to assess forecast uncertainty.

  1. How will climate change modify river flow regimes in Europe?

    Directory of Open Access Journals (Sweden)

    C. Schneider

    2012-08-01

    Full Text Available Worldwide, flow regimes are being modified by various anthropogenic impacts and climate change induces an additional risk. Rising evapotranspiration rates, declining snow cover and changing precipitation patterns will interact differently at different locations. Consequently, in distinct climate zones, unequal consequences can be expected in matters of water stress, flood risk, water quality, and food security. In particular, river ecosystems and their vital ecosystem services will be compromised as their species richness and composition have evolved over long time under natural flow conditions. This study aims at evaluating the exclusive impacts of climate change on river flow regimes in Europe. Various flow characteristics are taken into consideration and diverse dynamics are identified for each distinct climate zone in Europe. In order to simulate natural and modified flow regimes, the global hydrology model WaterGAP3 is applied. All calculations for current and future conditions (2050s are carried out on a 5' × 5' European grid. To address uncertainty, climate forcing data of three different global climate models are used to drive WaterGAP3. Finally, the hydrological alterations of different flow characteristics are quantified by the Indicators of Hydrological Alteration approach. Results of our analysis indicate that on European scale, climate change can be expected to modify flow regimes significantly. This is especially the case in the Mediterranean climate zone (due to drier conditions with reduced precipitation across the year and in the continental climate zone (due to reduced snowmelt and drier summers. Regarding single flow characteristics, strongest impacts on timing were found for the boreal climate zone. This applies for both, high and low flows. While low flow magnitudes are likely to be stronger influenced in the Mediterranean climate, high flow magnitudes will be mainly altered in snow climates with warmer summers. At the end

  2. Climate Change and Future Fire Regimes: Examples from California

    Directory of Open Access Journals (Sweden)

    Jon E. Keeley

    2016-08-01

    Full Text Available Climate and weather have long been noted as playing key roles in wildfire activity, and global warming is expected to exacerbate fire impacts on natural and urban ecosystems. Predicting future fire regimes requires an understanding of how temperature and precipitation interact to control fire activity. Inevitably this requires historical analyses that relate annual burning to climate variation. Fuel structure plays a critical role in determining which climatic parameters are most influential on fire activity, and here, by focusing on the diversity of ecosystems in California, we illustrate some principles that need to be recognized in predicting future fire regimes. Spatial scale of analysis is important in that large heterogeneous landscapes may not fully capture accurate relationships between climate and fires. Within climatically homogeneous subregions, montane forested landscapes show strong relationships between annual fluctuations in temperature and precipitation with area burned; however, this is strongly seasonal dependent; e.g., winter temperatures have very little or no effect but spring and summer temperatures are critical. Climate models that predict future seasonal temperature changes are needed to improve fire regime projections. Climate does not appear to be a major determinant of fire activity on all landscapes. Lower elevations and lower latitudes show little or no increase in fire activity with hotter and drier conditions. On these landscapes climate is not usually limiting to fires but these vegetation types are ignition-limited. Moreover, because they are closely juxtaposed with human habitations, fire regimes are more strongly controlled by other direct anthropogenic impacts. Predicting future fire regimes is not rocket science; it is far more complicated than that. Climate change is not relevant to some landscapes, but where climate is relevant, the relationship will change due to direct climate effects on vegetation

  3. Detecting regime shifts in the ocean: Data considerations [review article

    Science.gov (United States)

    deYoung, B.; Harris, R.; Alheit, J.; Beaugrand, G.; Mantua, N.; Shannon, L.

    2004-02-01

    We review observational data sets that have been used to detect regime shifts in the ocean. Through exploration of data time series we develop a definition of a regime shift from a pragmatic perspective, in which a shift is considered as an abrupt change from a quantifiable ecosystem state. We conclude that such changes represent a restructuring of the ecosystem state in some substantial sense that persists for long enough that a new quasi-equilibrium state can be observed. The abruptness of the shift is relative to the life-scale or the reproductive time-scale of the higher predators that are influenced by the shift. In general, the event-forcing is external to the biological ecosystem, usually the physical climate system, but we also identify shifts that can be ascribed to anthropogenic forcing, in our examples fishing. This pragmatic definition allows for several different types of regime shift ranging from simple biogeographic shifts to non-linear state changes. In practice it is quite difficult to determine whether observed changes in an oceanic ecosystem are primarily spatial or temporally regulated. The determination of ecosystem state remains an unresolved, and imprecise, oceanographic problem. We review observations and interpretation from several different oceanic regions as examples to illustrate this pragmatic definition of a regime shift: the Northeast Pacific, the Northwest and Northeast Atlantic, and Eastern Boundary Currents. For each region, different types of data (biological and physical) are available for differing periods of time, and we conclude, with varying degrees of certainty, whether a regime shift is in fact detectable in the data.

  4. Regimes of science production and diffusion: towards a transverse organization of knowledge

    Directory of Open Access Journals (Sweden)

    Anne Marcovich

    2012-01-01

    Full Text Available This article is a contribution to the critical sociology of science perspective introduced and developed by Pierre Bourdieu. The paper proposes a transversalist theory of science and technology production and diffusion. It is here argued that science and technology are comprised of multiple regimes where each regime is historically grounded, possesses its own division of labour, modes of cognitive and artifact production and has specific audiences. The major regimes include the disciplinary regime, utilitarian regime, transitory regime and research-technology regime. Though each regime is autonomous, they are simultaneously closely interlaced. In science and technology, autonomy is not antithetical to interdependence and reciprocity. This study demonstrates for the four specified regimes of production and diffusion that differentiation is not contrary to interaction. In science, differentiation and interaction comprise two sides of the same coin. All regimes exhibit a measure of transversality.

  5. Numerical simulation of flows from free molecular regime to continuum regime by a DVM with streaming and collision processes

    Science.gov (United States)

    Yang, L. M.; Shu, C.; Wu, J.; Wang, Y.

    2016-02-01

    A discrete velocity method (DVM) with streaming and collision processes is presented in this work for simulation of flows from free molecular regime to continuum regime. The present scheme can be considered as a semi-Lagrangian like scheme. At first, we follow the conventional DVM to discretize the phase velocity space by a number of discrete velocities. Then, for each discrete velocity, the kinetic equation with BGK-Shakhov model is integrated in space and time within one time step. As a result, a simple algebraic formulation can be obtained, and its solution can be marched in time by the streaming and collision processes. However, differently from the conventional semi-Lagrangian scheme, the present scheme uses the MUSCL approach with van Albada limiter in the process of reconstructing the distribution function at the surrounding points of the cell center, and the transport distance is controlled in order to avoid extrapolation. This makes the present scheme be capable of simulating the hypersonic rarefied flows. In addition, as compared to the unified gas kinetic scheme (UGKS), the present scheme is simpler and easier for implementation. Thus, the computational efficiency can be improved accordingly. To validate the proposed numerical scheme, test examples from free molecular regime to continuum regime are simulated. Numerical results showed that the present scheme can predict the flow properties accurately even for hypersonic rarefied flows.

  6. Exchange Rate Regimes – A periodical overview and a critical analysis of exchange rate regimes in Kosovo

    Directory of Open Access Journals (Sweden)

    Flamur Bunjaku

    2015-03-01

    Full Text Available Exchange rate regimes and the monetary policy are the key instruments governments use to achieve their economic and financial objectives. Moreover, due to global financial crisis the latter instruments get more importance. Empirical evidences show that exchange rate regimes in Kosovo and its monetary policy throughout their development were mainly influenced by different political and historical developments. In regard of Euroisation of monetary system in Kosovo it was found that this action generated macro - financial stability in terms of inflation and price fluctuation. However, in terms of microeconomic aspects, the unilateral adaptation of Euro as the official currency of Kosovo failed to provide microeconomic advantages such as to export stimulation, and so forth. The main exchange rate regime systems were discussed focusing in their advantages and disadvantages, and it was concluded that there is no commonly accepted theory regarding the optimality of exchange rate regimes. In addition, the global financial crisis impact in the financial system of Kosovo is also discussed and it was found that negative impacts of global financial crisis were moderate and indirect.

  7. Mechanical surface treatment of steel-Optimization parameters of regime

    Science.gov (United States)

    Laouar, L.; Hamadache, H.; Saad, S.; Bouchelaghem, A.; Mekhilef, S.

    2009-11-01

    Mechanical treatment process by superficial plastic deformation is employed for finished mechanical part surface. It introduces structural modifications that offer to basic material new properties witch give a high quality of physical and geometrical on superficial layers. This study focuses on the application of burnishing treatment (ball burnishing) on XC48 steel and parameters optimisation of treatment regime. Three important parameters were considered: burnishing force ' Py', burnishing feed 'f' and ball radius 'r'. An empirical model has been developed to illustrate the relationship between these parameters and superficial layer characteristics defined by surface roughness ' Ra' and superficial hardness ' Hv'. A program was developed in order to determine the optimum treatment regimes for each characteristic.

  8. Nano-optomechanical measurement in the photon counting regime

    CERN Document Server

    de Lépinay, Laure Mercier; Rohr, Sven; Gloppe, Arnaud; Kuhn, Aurélien; Verlot, Pierre; Dupont-Ferrier, Eva; Besga, Benjamin; Arcizet, Olivier

    2015-01-01

    Optically measuring in the photon counting regime is a recurrent challenge in modern physics and a guarantee to develop weakly invasive probes. Here we investigate this idea on a hybrid nano-optomechanical system composed of a nanowire hybridized to a single Nitrogen-Vacancy (NV) defect. The vibrations of the nanoresonator grant a spatial degree of freedom to the quantum emitter and the photon emission event can now vary in space and time. We investigate how the nanomotion is encoded on the detected photon statistics and explore their spatio-temporal correlation properties. This allows a quantitative measurement of the vibrations of the nanomechanical oscillator at unprecedentedly low light intensities in the photon counting regime when less than one photon is detected per oscillation period, where standard detectors are dark-noise-limited. These results have implications for probing weakly interacting nanoresonators, for low temperature experiments and for investigating single moving markers.

  9. Pulsar Timing Arrays and Gravity Tests in the Radiative Regime

    CERN Document Server

    Lee, K J

    2014-01-01

    In this paper, we focus on testing gravity theories in the radiative regime using pulsar timing array observations. After reviewing current techniques to measure the dispersion and alternative polarization of gravitational waves, we extend the framework to the most general situations, where the combinations of a massive graviton and alternative polarization modes are considered. The atlas of the Hellings-Downs functions is completed by the new calculations for these dispersive alternative polarization modes. We find that each mode and corresponding graviton mass introduce characteristic features in the Hellings-Downs function. Thus, in principal, we can not only detect each polarization mode, measure the corresponding graviton mass, but also discriminate the different scenarios. In this way, we can test gravity theories in the radiative regime in a generalized fashion, and such method is a direct experiment, where one can address the gauge symmetry of the gravity theories in their linearised limits. Although ...

  10. New Mobilities Regimes in Art and Social Sciences

    DEFF Research Database (Denmark)

    Witzgall, Susanne; Vogl, Gerlinde; Kesselring, Sven

    New Mobilities Regimes analyses how global mobilities are changing the world of today and the role of political and economic power. Bringing together essays by leading scholars and social scientists, including Mimi Sheller and Bülent Diken with the work of well-known artists and art theorists....... Illustrated by a range of studies which examine the regulation and structure of mobility, such as the daily routines of teleworkers, Ukrainian cleaners in Western Europe, the mobility policies of global corporations, and the impact of bicycle policies on public space, New Mobilities Regimes emphasizes...... the routes and crossroads of migration flows as well as at the interaction of mobility and new spatial concepts. The contributors are concerned with both the positive outcomes and the disappointments of the global mobilizations in modern lives. This book is ground-breaking in that it calls...

  11. The case for regime-based water quality standards

    Science.gov (United States)

    Poole, Geoffrey C.; Dunham, J.B.; Keenan, D.M.; Sauter, S.T.; McCullough, D.A.; Mebane, Christopher; Lockwood, Jeffrey C.; Essig, Don A.; Hicks, Mark P.; Sturdevant, Debra J.; Materna, E.J.; Spalding, M.; Risley, John; Deppman, Marianne

    2004-01-01

    Conventional water quality standards have been successful in reducing the concentration of toxic substances in US waters. However, conventional standards are based on simple thresholds and are therefore poorly structured to address human-caused imbalances in dynamic, natural water quality parameters, such as nutrients, sediment, and temperature. A more applicable type of water quality standarda??a a??regime standarda??a??would describe desirable distributions of conditions over space and time within a stream network. By mandating the protection and restoration of the aquatic ecosystem dynamics that are required to support beneficial uses in streams, well-designed regime standards would facilitate more effective strategies for management of natural water quality parameters.

  12. Adaptive two-regime method: application to front propagation

    CERN Document Server

    Robinson, Martin; Erban, Radek

    2013-01-01

    The Adaptive Two-Regime Method (ATRM) is developed for hybrid (multiscale) stochastic simulation of reaction-diffusion problems. It efficiently couples detailed Brownian dynamics simulations with coarser lattice-based models. The ATRM is a generalization of the previously developed Two-Regime Method [Flegg et al, Journal of the Royal Society Interface, 2012] to multiscale problems which require a dynamic selection of regions where detailed Brownian dynamics simulation is used. Typical applications include a front propagation or spatio-temporal oscillations. In this paper, the ATRM is used for an in-depth study of front propagation in a stochastic reaction-diffusion system which has its mean-field model given in terms of the Fisher equation [Fisher, Annals of Eugenics, 1937]. It exhibits a travelling reaction front which is sensitive to stochastic fluctuations at the leading edge of the wavefront. Previous studies into stochastic effects on the Fisher wave propagation speed have focused on lattice-based models...

  13. A Cold-Strontium Laser in the Superradiant Crossover Regime

    CERN Document Server

    Norcia, Matthew A

    2015-01-01

    Recent proposals suggest that lasers based on narrow dipole-forbidden transitions in cold alkaline earth atoms could achieve linewidths that are orders of magnitude smaller than linewidths of any existing lasers. Here, we demonstrate a laser based on the 7.5 kHz linewidth dipole forbidden $^3 $P$_1$ to $^1 $S$_0$ transition in laser-cooled and tightly confined $^{88}$Sr. We can operate this laser in the bad-cavity regime, where coherence is primarily stored in the atoms, or continuously tune to the more conventional good-cavity regime, where coherence is primarily stored in the light field. We show that the cold-atom gain medium can be repumped to achieve quasi steady-state lasing, and demonstrate up to an order of magnitude suppression in the sensitivity of laser frequency to changes in cavity length, the primary limitation for the most frequency stable lasers today.

  14. A Cold-Strontium Laser in the Superradiant Crossover Regime

    Science.gov (United States)

    Norcia, Matthew; Thompson, James

    2016-05-01

    We demonstrate and study a laser based on the 7.5 kHz linewidth dipole forbidden 3 P1 to 1 S0 transition in laser-cooled and tightly confined 88 Sr. We can operate this laser in the bad-cavity or superradiant regime, where coherence is primarily stored in the atoms, or continuously tune to the more conventional good-cavity regime, where coherence is primarily stored in the light field. We show that the cold-atom gain medium can be repumped to achieve quasi steady-state lasing. We also demonstrate up to an order of magnitude suppression in the sensitivity of laser frequency to changes in cavity length, verifying a key feature of proposed narrow linewidth lasers based on dipole-forbidden transitions in alkaline earth atoms.

  15. Option Pricing when the Regime-Switching Risk is Priced

    Institute of Scientific and Technical Information of China (English)

    Tak Kuen Siu; Hailiang Yang

    2009-01-01

    We study the pricing of an option when the price dynamic of the underlying risky asset is governed by a Markov-modulated geometric Brownian motion. We suppose that the drift and volatility of the underlying risky asset are modulated by an observable continuous-time, finite-state Markov chain. We develop a twostage pricing model which can price both the diffusion risk and the regime-switching risk based on the Esscher transform and the minimization of the maximum entropy between an equivalent martingale measure and the real-world probability measure over different states. Numerical experiments are conducted and their results reveal that the impact of pricing regime-switching risk on the option prices is significant.

  16. Onset of the Asymptotic Regime for Finite Orders

    CERN Document Server

    Henson, Joe; Sorkin, Rafael D; Surya, Sumati

    2015-01-01

    We describe a Markov-Chain-Monte-Carlo algorithm which can be used to generate naturally labeled n-element posets at random with a probability distribution of one's choice. Implementing this algorithm for the uniform distribution, we explore the approach to the asymptotic regime in which almost every poset takes on the three-layer structure described by Kleitman and Rothschild (KR). By tracking the n-dependence of several order-invariants, among them the height of the poset, we observe an oscillatory behavior which is very unlike a monotonic approach to the KR regime. Only around n=40 or so does this "finite size dance" appear to give way to a gradual crossover to asymptopia which lasts until n=85, the largest n we have simulated.

  17. Biphoton spectroscopy in a strongly nondegenerate regime of SPDC

    International Nuclear Information System (INIS)

    The absorption spectrum of Cr3+ ions in Al2O3 crystal in the range from 691 nm to 697 nm was measured at the room temperature using the biphoton light generated by nondegenerate spontaneous parametric down-conversion of the He-Cd laser radiation (325 nm) in the LiIO3 crystal. The spectrum of the sample was measured by counting the coincidences when signal photons go through the impurity crystal, whilst the wavelength of the idler photons is resolved by a monochromator. A strongly nondegenerate regime of SPDC, when the difference in frequencies of correlated photons exceeds significantly their spectral width, was used in the biphoton spectroscopy for the first time. Such a regime allows one to obtain an absorption spectrum by measuring the wavelength in a completely different spectral range

  18. Biphoton spectroscopy in a strongly nondegenerate regime of SPDC

    Science.gov (United States)

    Kalachev, A. A.; Kalashnikov, D. A.; Kalinkin, A. A.; Mitrofanova, T. G.; Shkalikov, A. V.; Samartsev, V. V.

    2008-08-01

    The absorption spectrum of Cr3+ ions in Al2O3 crystal in the range from 691 nm to 697 nm was measured at the room temperature using the biphoton light generated by nondegenerate spontaneous parametric down-conversion of the He-Cd laser radiation (325 nm) in the LiIO3 crystal. The spectrum of the sample was measured by counting the coincidences when signal photons go through the impurity crystal, whilst the wavelength of the idler photons is resolved by a monochromator. A strongly nondegenerate regime of SPDC, when the difference in frequencies of correlated photons exceeds significantly their spectral width, was used in the biphoton spectroscopy for the first time. Such a regime allows one to obtain an absorption spectrum by measuring the wavelength in a completely different spectral range.

  19. Adult learning, education, and the labour market inthe employability regime

    Directory of Open Access Journals (Sweden)

    Staffan Nilsson

    2013-10-01

    Full Text Available The purpose of this paper is to draw on the research and scholarly literature to explorethe changing discourses and perspectives concerning adult learning, education, and thelabour market in the employability regime. The focus of the nalysis is a Nordic context.The dominant employability regime maintains a technical-rational perspective onlearning and employability. Education is predominantly regarded as an instrumentalpreparation for the labour market. The future demands of the labour market are largelyunknown, however, and vocational and professional training may not provide sufficientpreparation for the increasing complexities of work. Theoretical discussions have beendominated by an alleged mismatch between individual competence and thequalifications that are required in the world of work. There is no consensus regardinghow the gap should be described, explained, or bridged. New demands on educationaldesign have emerged, and ideas related to liberal education and ‘bildung’ have beenreinserted into the political agenda, offering general preparation for a wider array ofchallenges.

  20. Heavy ion acceleration in the Breakout Afterburner regime

    CERN Document Server

    Petrov, G M; Thomas, A G R; Krushelnick, K; Beg, F N

    2015-01-01

    Theoretical study of heavy ion acceleration from an ultrathin (20 nm) gold foil irradiated by sub-picosecond lasers is presented. Using two dimensional particle-in-cell simulations we identified two highly efficient ion acceleration schemes. By varying the laser pulse duration we observed a transition from Radiation Pressure Acceleration to the Breakout Afterburner regime akin to light ions. The underlying physics and ion acceleration regimes are similar to that of light ions, however, nuances of the acceleration process make the acceleration of heavy ions more challenging. Two laser systems are studied in detail: the Texas Petawatt Laser and the Trident laser, the former having pulse duration 180 fs, intermediate between very short femtosecond pulses and picosecond pulses. Both laser systems generated directional gold ions beams (~10 degrees half-angle) with fluxes in excess of 1011 ion/sr and normalized energy >10 MeV/nucleon.

  1. The regime and the constitutional principles from 1938

    Directory of Open Access Journals (Sweden)

    Florin Grecu

    2012-12-01

    Full Text Available The authoritarian monarchy regime, from 1938-1940, functioned based on an exceptional status, because it was founded on a decree-law of state of siege and therefore all the power in the State was held in the hands of the army colonels and generals. By suspending the political parties, the political pluralism and the Parliament, the basic institutions of a democratic regime were abolished. Press censorship, the denying of the right to manifest and gather were assigned to the army and the militarization of the State institutions became a reality. The proclamation of the King as an absolute leader of the unique party and of the government transformed Romania into a ministerial and undemocratic monarchy, with authoritarian valence.

  2. Automatic Classification of Offshore Wind Regimes With Weather Radar Observations

    DEFF Research Database (Denmark)

    Trombe, Pierre-Julien; Pinson, Pierre; Madsen, Henrik

    2014-01-01

    fluctuations. The information they provide could then be integrated into an advanced prediction system for improving offshore wind power predictability and controllability. In this paper, we address the automatic classification of offshore wind regimes (i.e., wind fluctuations with specific frequency...... systems are extracted from weather radar images. These attributes describe the global intensity, spatial continuity and motion of precipitation echoes on the images. Finally, a CART classification tree is used to find the broad relationships between precipitation attributes and wind regimes......Weather radar observations are called to play an important role in offshore wind energy. In particular, they can enable the monitoring of weather conditions in the vicinity of large-scale offshore wind farms and thereby notify the arrival of precipitation systems associated with severe wind...

  3. THE POLICY AND THE TRADE REGIME IN ROMANIA AFTER 1990

    Directory of Open Access Journals (Sweden)

    Dobrotă Gabriela

    2009-11-01

    Full Text Available The growth of connections between national economies has generated a consolidation of foreign currency activities, requiring a continuous adjusting regime, both for the foreign currency policy and for the exchange rate to the market mechanisms. In Romania, there have been frequent alterations of the foreign currency policy, requiring the need to create a juridical framework adequate for the market economy and the evolution of financial instruments. This paper presents the main characteristics of the trade regime and the exchange rate policy in Romania after 1990. Practically, the paper reflects a radiography of the main events on the Romanian foreign exchange rate within the context of specific conditions of the Romanian economy and in correlation with the measures adopted by countries from the Central Europe.

  4. THE POLICY AND THE TRADE REGIME IN ROMANIA AFTER 1990

    Directory of Open Access Journals (Sweden)

    Dobrotă Gabriela

    2009-11-01

    Full Text Available The growth of connections between national economies has generated a consolidation of foreign currency activities, requiring a continuous adjusting regime, both for the foreign currency policy and for the exchange rate to the market mechanisms. In Romania, there have been frequent alterations of the foreign currency policy, requiring the need to create a juridical framework adequate for the market economy and the evolution of financial instruments. This paper presents the main characteristics of the trade regime and the exchange rate policy in Romania after 1990. Practically, the paper reflects a radiography of the main events on the Romanian foreign exchange rate within the context of specific conditions of the Romanian economy and in correlation with the measures adopted by countries from the Central Europe

  5. Relationship between fire regime and vegetation symphenological timing in Sardinia

    Directory of Open Access Journals (Sweden)

    Carlo Ricotta

    2008-01-01

    Full Text Available Fire is a basic ecological factor that contributes to determine vegetation biodiversity and dynamics in time and space. Fuel characteristics play an essential role in fire ignition and propagation; for instance fuel availability and flammability are closely related to the coarse-scale vegetation phenological trends that directly affect wildfire distribution in time and space. In this perspective, the annual NDVI profiles derived from high temporal resolution satellite images like SPOT Vegetation represent an effective tool for monitoring plant seasonal dynamics at the landscape scale. The objective of this study consists in relating the wildfire regime in Sardinia during 2000-2004 with the remotely sensed phenological parameters of the vegetation, segmented according to potential natural vegetation characteristics. The results of our study highlight a good correspondence between the NDVI temporal dynamics of the potential natural vegetation of Sardinia and the corresponding fires regime characteristics.

  6. $H_{2}$ Formation on Interstellar Grains in Different Physical Regimes

    CERN Document Server

    Biham, O; Katz, N; Pirronello, V; Vidali, G

    1998-01-01

    An analysis of the kinetics of H2 formation on interstellar dust grains is presented using rate equations. It is shown that semi-empirical expressions that appeared in the literature represent two different physical regimes. In particular, it is shown that the expression given by Hollenbach, Werner and Salpeter [ApJ, 163, 165 (1971)] applies when high flux, or high mobility, of H atoms on the surface of a grain, makes it very unlikely that H atoms evaporate before they meet each other and recombine. The expression of Pirronello et al.\\ [ApJ, 483, L131 (1997)] -- deduced on the basis of accurate measurements on realistic dust analogue -- applies to the opposite regime (low coverage and low mobility). The implications of this analysis for the understanding of the processes dominating in the Interstellar Medium are discussed.

  7. Accretion to a Magnetized Neutron Star in the "Propeller" Regime

    CERN Document Server

    Toropina, O D; Lovelace, R V E

    2006-01-01

    We investigate spherical accretion to a rotating magnetized star in the "propeller" regime using axisymmetric resistive magnetohydrodynamic simulations. The regime is predicted to occur if the magnetospheric radius is larger than the corotation radius and smaller than the light cylinder radius. The simulations show that accreting matter is expelled from the equatorial region of the magnetosphere and that it moves away from the star in a supersonic, disk-shaped outflow. At larger radial distances the outflow slows down and becomes subsonic. The equatorial matter outflow is initially driven by the centrifugal force, but at larger distances the pressure gradient force becomes significant. We find the fraction of the Bondi accretion rate which accretes to the surface of the star.

  8. Multifractal regime transition in a modified minority game model

    International Nuclear Information System (INIS)

    The search for more realistic modeling of financial time series reveals several stylized facts of real markets. In this work we focus on the multifractal properties found in price and index signals. Although the usual minority game (MG) models do not exhibit multifractality, we study here one of its variants that does. We show that the nonsynchronous MG models in the nonergodic phase is multifractal and in this sense, together with other stylized facts, constitute a better modeling tool. Using the structure function (SF) approach we detected the stationary and the scaling range of the time series generated by the MG model and, from the linear (non-linear) behavior of the SF we identified the fractal (multifractal) regimes. Finally, using the wavelet transform modulus maxima (WTMM) technique we obtained its multifractal spectrum width for different dynamical regimes.

  9. Political regime and human capital: A cross-country analysis

    OpenAIRE

    Klomp, J.G.; Haan

    2013-01-01

    We examine the relationship between different dimensions of the political regime in place and human capital using a two-step structural equation model. In the first step, we employ factor analysis on 16 human capital indicators to construct two new human capital measures (basic and advanced human capital). In the second step, we estimate the impact of our political variables on human capital, using a cross-sectional structural model for some 100 countries. We conclude that democracy is positi...

  10. CHALLENGES FOR ADOPTING INFLATION TARGETING REGIME IN EGYPT

    OpenAIRE

    Awad, Ibrahim

    2013-01-01

    This study intends to investigate challenges facing the CBE for adopting IT regime. Through exploiting the experience of Czech Republic, Poland, and Brazil in the early days of their adopting IT the study underscores the following challenges; (i) A more active role to be played by the CBE is needed to convince decision-making circuits inside the government for the adoption of IT. (ii) The CBE should be factually independent. (iii) Coordination between monetary policy and fiscal policy should ...

  11. An optimal learning method for developing personalized treatment regimes

    OpenAIRE

    Wang, Yingfei; Powell, Warren

    2016-01-01

    A treatment regime is a function that maps individual patient information to a recommended treatment, hence explicitly incorporating the heterogeneity in need for treatment across individuals. Patient responses are dichotomous and can be predicted through an unknown relationship that depends on the patient information and the selected treatment. The goal is to find the treatments that lead to the best patient responses on average. Each experiment is expensive, forcing us to learn the most fro...

  12. The advantage of international fiscal cooperation under alternative monetary regimes

    DEFF Research Database (Denmark)

    Jensen, Henrik

    1996-01-01

    We consider the strategic interplay between international monetary and fiscal cooperation in a world of interdependent economies. Motivated by the ongoing discussion of monetary unification of Europe, focus is on monetary cooperation, and in particular how its performance is altered by the...... introduction of fiscal (tax) cooperation. Our main result is that fiscal cooperation may be disadvantageous when monetary cooperation lacks credibility with private sectors. On the other hand, fiscal cooperation under a rule based monetary regime is always advantageous...

  13. FISCAL REGIMES IN AND OUTSIDE THE MENA REGION

    OpenAIRE

    IBRAHIM AHMED ELBADAWI; RAIMUNDO SOTO

    2013-01-01

    The 1990s ushered the world not only into a democracy wave, following the collapse of the former Soviet Union, but also into a wave of Fiscal Rules, where the number of countries adopting this fiscal regime steadily rose from only 10 in 1990 to 97 in 2009. Countries that depend on hydrocarbons, in general, tend to suffer from fiscal policies that are highly susceptible to energy price shocks. This provides incentives for implementing fiscal stabilization instruments in the form of fiscal rule...

  14. PHENOMENON OF RESCUING VICTIMS OF NAZI REGIME UNDER THE HOLOCAUST

    OpenAIRE

    Stets, Oleg; Kovtun, Alexander

    2015-01-01

    In this article problems devoted to participation of the local Ukrainian population at the rescue of Jewry victims of the Nazi occupation regime is examined. Question of violation of human rights is analyzed and it is given description a concept «the phenomenon of rescuing». It was concluded on social and legal support rescuers Jewish people during the Second World War on the territory of modern Ukraine.

  15. Capacity of Fading Channels in the Low Power Regime

    KAUST Repository

    Benkhelifa, Fatma

    2013-01-01

    The low power regime has attracted various researchers in the information theory and communication communities to understand the performance limits of wireless systems. Indeed, the energy consumption is becoming one of the major limiting factors in wireless systems. As such, energy-efficient wireless systems are of major importance to the next generation wireless systems designers. The capacity is a metric that measures the performance limit of a wireless system. The study of the ergodic capacity of some fading channels in the low power regime is the main subject of this thesis. In our study, we consider that the receiver has always a full knowledge of the channel state information. However, we assume that the transmitter has possibly imperfect knowledge of the channel state information, i.e. he knows either perfectly the channel or only an estimated version of the channel. Both radio frequency and free space optical communication channel models are considered. The main contribution of this work is the explicit characterization of how the capacity scales as function of the signal-to-noise ratio in the low power regime. This allows us to characterize the gain due to the perfect knowledge compared to no knowledge of the channel state information at the transmitter. In particular, we show that the gain increases logarithmically for radio frequency communication. However, the gain increases as log2(Pavg) or log4(Pavg) for free-space optical communication, where Pavg is the average power constraint imposed to the input. Furthermore, we characterize the capacity of cascaded fading channels and we applied the result to Rayleigh-product fading channel and to a free-space optical link over gamma-gamma atmospheric turbulence in the presence of pointing errors. Finally, we study the capacity of Nakagami-m fading channel under quality of service constraints, namely the effective capacity. We have shown that the effective capacity converges to Shannon capacity in the very low

  16. Electricity Price Modelling with a Regime Switching Volatility

    OpenAIRE

    Silvana Musti; Viviana Fanelli

    2010-01-01

    We present a methodology to model electricity price dynamics by applying the interest rate theory toolkit. We construct the electricity market following [16] and applying the Heath, Jarrow and Morton ([7]) model. The electricity returns forward curve evolution using the Regime Switching Volatility is the instrument chosen to reflect into a simulating model the natural seasonality of electricity prices. The model calibration and the volatility parameters estimation allow to simulate in a reali...

  17. World-Ecology and Ireland: The Neoliberal Ecological Regime

    OpenAIRE

    Sharae Deckard

    2016-01-01

    Since the collapse of the Celtic Tiger, the socio-economic particularity of neoliberal capitalism in its Irish manifestation has increasingly been critiqued, but little attention has been paid to neoliberalism as ecology within Ireland. This article conducts an exploratory survey of the characteristics of the Irish neoliberal ecological regime during and after the Celtic Tiger, identifying the opening of new commodity frontiers (such as fracking, water, agro-biotechnology, and biopharma) cons...

  18. Amendment of the Foreign lnvestment Juridical regime in Colombia

    Directory of Open Access Journals (Sweden)

    Cristina Vargas Guzman

    1992-12-01

    Full Text Available Colombia, integrated in the Andean Group, is now going through a period of economic and institutional modernization and has initiated a serie of modifications, specially of its international trade, finantial, tax, exchange and labour regimes. These have involved some changes which guarantee legislative stability to investors and thus set the grounds for the foreign participation in the economic modernization and internationalization process in Colombia. These facilities need the support of developed countries to achieve its aims.

  19. Decision Making under Ecological Regime Shift: An Experimental Economic Approach

    OpenAIRE

    Kawata, Yukichika

    2011-01-01

    Environmental economics postulates the assumption of homo economicus and presumes that externality occurs as a result of the rational economic activities of economic agents. This paper examines this assumption using an experimental economic approach in the context of regime shift, which has been receiving increasing attention. We observe that when externality does not exist, economic agents (subjects of experimemt) act economically rationally, but when externality exists, economic agents avoi...

  20. Steady state plasma operation in RF dominated regimes on EAST

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X. J.; Zhao, Y. P.; Gong, X. Z.; Hu, C. D.; Liu, F. K.; Hu, L. Q.; Wan, B. N., E-mail: bnwan@ipp.ac.cn; Li, J. G. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2015-12-10

    Significant progress has recently been made on EAST in the 2014 campaign, including the enhanced CW H&CD system over 20MW heating power (LHCD, ICRH and NBI), more than 70 diagnostics, ITER-like W-monoblock on upper divertor, two inner cryo-pumps and RMP coils, enabling EAST to investigate long pulse H mode operation with dominant electron heating and low torque to address the critical issues for ITER. H-mode plasmas were achieved by new H&CD system or 4.6GHz LHCD alone for the first time. Long pulse high performance H mode has been obtained by LHCD alone up to 28s at H{sub 98}∼1.2 or by combing of ICRH and LHCD, no or small ELM was found in RF plasmas, which is essential for steady state operation in the future Tokamak. Plasma operation in low collision regimes were implemented by new 4.6GHz LHCD with core Te∼4.5keV. The non-inductive scenarios with high performance at high bootstrap current fraction have been demonstrated in RF dominated regimes for long pulse operation. Near full non-inductive CD discharges have been achieved. In addition, effective heating and decoupling method under multi-transmitter for ICRF system were developed in this campaign, etc. EAST could be in operation with over 30MW CW heating and current drive power (LHCD ICRH NBI and ECRH), enhanced diagnostic capabilities and full actively-cooled metal wall from 2015. It will therefore allow to access new confinement regimes and to extend these regimes towards to steady state operation.

  1. Potential Effects of Climate Change on Mixed Severity Fire Regimes

    OpenAIRE

    Halofsky, Jessica; Peterson, Dave L.

    2009-01-01

    The frequency, severity, and extent of wildfire are strongly related to climate, and increasing temperatures with climate change will likely lead to changes in fire regimes in many types of ecosystems. Increased spring and summer temperatures with climate change will result in relatively early snowmelt, lower summer soil and fuel moisture, and longer fire seasons in the West. These conditions will lead to increased fire frequency and extent. Higher temperatures may also interact with vegetati...

  2. International arbitration and its exclusion from the Brussels regime

    Directory of Open Access Journals (Sweden)

    Hamed Alavi

    2016-06-01

    Full Text Available The Brussels regime, which regulates the matters of transnational litigation excludes arbitration from its scope. Upon formation of the Brussels regime the existing instruments concerning arbitration - the United Nations Convention on Recognition and Enforcement of Foreign Arbitral Awards and the 1961 European Convention on International Commercial Arbitration - were believed to be sufficient. The original Brussels Convention 1968 on recognition and enforcement of judgments delivered in the courts of the EU Member States expressly provided for the exclusion of arbitration. The following Brussels I Regulation followed the trend and reinforced the exclusion of arbitration from their material scopes. The rationale for doing so was primarily the prevention of parallel proceedings and irreconcilable judgments. The arbitration exclusion from the Brussels regime has caused a fair amount of confusion, especially regarding the extent and limits of the exclusion. That is, whether the arbitration agreement, the arbitral award and its consequences are covered by the exclusion or they may fall under the scope of the Brussels regulation if they constitute only an incidental question to the main cause of action? The confusion was illustrated in the ECJ judgment West Tankers, which generated negative feedback from the arbitration community and indicated the need for reform. The recently adopted Recast Regulation took it upon itself to clarify the relationship between arbitration and the EU regime of transnational litigation. The exclusion is reinforced ye again and its boundaries are specified in the Preamble. However, whether or not the concerns about the extent and objectives of arbitration exclusion have been at present eliminated, remains to be seen.

  3. Power Counting Regime of Chiral Extrapolation and Beyond

    CERN Document Server

    Leinweber, D B; Young, R D; Leinweber, Derek B; Thomas, Anthony W; Young, Ross D

    2005-01-01

    Finite-range regularised (FRR) chiral effective field theory is presented in the context of approximation schemes ubiquitous in modern lattice QCD calculations. Using FRR techniques, the power-counting regime (PCR) of chiral perturbation theory can be estimated. To fourth-order in the expansion at the 1% tolerance level, we find m_\\pi < 180 MeV for the PCR, extending only a small distance beyond the physical pion mass.

  4. THERMAL RADIATION LOAD ON TEMPERATURE REGIMES IN PLANT GROWTH CHAMBERS

    OpenAIRE

    Hamasaki, T; Okada, Masumi

    2000-01-01

    In enclosed environments such as a plant growth chamber, thermal radiation plays an important role in determining heat balance and therefore the resultant temperature regimes. In artificially illuminated chambers, a significant level of thermal radiation is emitted from the lamps and/or the lamp house surface. Though there are both shortwave and longwave components in thermal radiation, our measurements in two different chamber designs, with and without thermal radiation filters, showed the l...

  5. Corporate hedging under a resource rent tax regime

    OpenAIRE

    Frestad, Dennis

    2010-01-01

    In addition to the ordinary corporate income tax, special purpose taxes are sometimes levied to extract abnormal profits arising from the use of natural resources. Such dual tax regimes exist in Norway for oil and hydropower, where the corresponding special purpose tax bases are unaffected by any derivatives payments. Dual tax firms with hedging programs therefore face the risk of potentially large discrepancies between the tax bases for corporate income tax and special purpose tax. I investi...

  6. Performance of different tomato cultivars under organic and inorganic regimes

    International Nuclear Information System (INIS)

    To study the performance of different tomato cultivars under organic and inorganic regimes an experiment was conducted at New Developmental Farm, The University of Agriculture, Peshawar, Pakistan during the summer 2013-14. The experiment was laid out in RCBD with split plot arrangement having four replications. Organic regimes (FYM, poultry manure and mushroom compost) and inorganic (NPK) regimes were allotted to main plot, while cultivars (Roma VF, Roma, Super Classic, Bambino and Rio Grande) were subjected to sub plots. Organic and Inorganic regimes significantly (P ≤ 0.01) influenced all the studied attributes of tomato cultivars. Among different cultivars, Roma gave maximum plant survival (93.8 percentage), number of leaves plant (84.1), number of flower inflorescence (5.4), number of fruits inflorescence (4.3), number of fruit plant (25.4), fruit size (63.9 cm) fruit weight plant (9.1 kg) and total yield (22.9 t ha). However, it was closely followed by cultivar Rio Grande for number of leaves plant (79.6), number of flower inflorescence (5.1), number of fruits inflorescence (4.0) and number of fruits plant (24.9). Cultivar Super Classic produced minimum number of leaves plant (67.7), flower inflorescence (4.8), fruit size (60.6 cm), fruit weight plant (8.6 kg) and total yield (21.7 t ha). Similarly, highest plant survival (90.0 percentage), number of flower inflorescence (5.1), number of fruits inflorescence (4.0), number of fruit plant (25.4), fruit size (62.4 ml), fruit weight plant (8.90 kg) and total yield (22.9 t ha) were recorded in plants provided with organic conditions Roma cultivar performed better than other cultivars under the agro climatic condition of Peshawar followed by cultivar Rio Grande. Therefore, organic tomato production, and these two cultivars are recommended to be grown in Peshawar area. (author)

  7. Modeling whistler wave generation regimes in magnetospheric cyclotron maser

    OpenAIRE

    D. L. Pasmanik; A. G. Demekhov; V. Y. Trakhtengerts; M. Parrot

    2004-01-01

    Numerical analysis of the model for cyclotron instability in the Earth's magnetosphere is performed. This model, based on the self-consistent set of equations of quasi-linear plasma theory, describes different regimes of wave generation and related energetic particle precipitation. As the source of free energy the injection of energetic electrons with transverse anisotropic distribution function to the interaction region is considered. A parametric study of the model is performed. The ma...

  8. Idealized Simulations of Precipitation Regimes over Small Tropical Islands

    Science.gov (United States)

    Wang, S.; Sobel, A. H.

    2014-12-01

    Tropical islands are global focal points of convection. Observational studies have shown that precipitation over tropical islands is strongly regulated by their size and elevation, and by the large scale prevailing wind. To further develop physical understanding of convection over tropical islands, we perform a set of highly idealized simulations with uniform sea surface temperature to explore flow regimes around an idealized small island (~120 km wide) as a function of large scale wind speed and island elevation. In our simulations the domain as a whole is in radiative-convective equilibrium (RCE), which constrains the domain average precipitation. The island occupies a small part of the domain, so that significant precipitation variations over the island can occur, compensated by smaller anomalies over the larger surrounding area. Over flat islands, as we vary prevailing wind speed, the island experiences three distinct flow regimes: rainfall is greatly enhanced and a local symmetric circulation is formed in the time mean around the island when the prevailing large scale wind speed is small (0 m/s); but there is little rainfall enhancement when the wind speed is increased to a moderate value (~5 m/s). We interpret these two regimes as the shift of triggering mechanism of convection: thermally forced convection due to surface solar heating dominates when large scale wind is very weak, while mechanically forced convection is favored when the impinging wind is moderate. Further increase of the prevailing wind speed to large values leads to strong asymmetry in the windward and leeward side of island and its coastal area, likely due to gravity waves from flow passing over elevated diurnal heating. Topography has a quantitative impact, but does not alter the qualitative shift of flow regimes as a function of wind speed.

  9. Improving entanglement of two atoms in strong coupling regime

    Science.gov (United States)

    Liu, Hui; Yang, Qing; Yang, Ming; Cao, Zhuoliang

    2016-03-01

    We consider a model of two identical atoms coupled to a single-mode cavity. When in atom-field strong coupling regime, the entanglement of the two atoms with spontaneous emission should be investigated beyond rotating-wave approximation (RWA). In order to improve the entanglement of the two atoms, some typical feedback based on quantum-jump are attempted to impose on the atoms. The result of numerical simulations shows that an appropriate feedback control can improve the entanglement.

  10. Nano-plasmonic antennas in the near infrared regime.

    Science.gov (United States)

    Berkovitch, N; Ginzburg, P; Orenstein, M

    2012-02-22

    Plasmonic nano-antennas constitute a central research topic in current science and engineering with an enormous variety of potential applications. Here we review the recent progress in the niche of plasmonic nano-antennas operating in the near infrared part of the spectrum which is important for a variety of applications. Tuning of the resonance into the near infrared regime is emphasized in the perspectives of fabrication, measurement, modeling, and analytical treatments, concentrating on the vast recent achievements in these areas.

  11. Regime-switching models to study psychological process

    OpenAIRE

    Hamaker, E.L.; Grasman, R.P.P.P.; Kamphuis, J.H.

    2010-01-01

    Many psychological processes are characterized by recurrent shifts between different states. To model these processes at the level of the individual, regime-switching models may prove useful. In this chapter we discuss two of these models: the threshold autoregressive model and the Markov switching autoregressive model. We discuss their main features, and propose estimation methods that can handle missing data. We apply these models to daily affect measurements of an individual diagnosed with...

  12. Practical stability and instability of regime-switching diffusions

    Institute of Scientific and Technical Information of China (English)

    G.George YIN; Bo ZHANG; Chao ZHU

    2008-01-01

    This work is devoted to practical stability of a class of regime-switching diffusions.First,the notion of practical stability is introduced.Then,sufficient conditions for practical stability and practical instability in probability and in pth mean are provided using a Lyapunov function argument.In addition,easily verifiable conditions on drift and diffusion coefficients are also given.Moreover,examples are supplied for demonstration purposes.

  13. MCNP/X TRANSPORT IN THE TABULAR REGIME

    Energy Technology Data Exchange (ETDEWEB)

    HUGHES, H. GRADY [Los Alamos National Laboratory

    2007-01-08

    The authors review the transport capabilities of the MCNP and MCNPX Monte Carlo codes in the energy regimes in which tabular transport data are available. Giving special attention to neutron tables, they emphasize the measures taken to improve the treatment of a variety of difficult aspects of the transport problem, including unresolved resonances, thermal issues, and the availability of suitable cross sections sets. They also briefly touch on the current situation in regard to photon, electron, and proton transport tables.

  14. Analytic expression for poloidal flow velocity in the banana regime

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, M. [College of Industrial Technology, Nihon University, Narashino 275-8576 (Japan)

    2013-01-15

    The poloidal flow velocity in the banana regime is calculated by improving the l = 1 approximation for the Fokker-Planck collision operator [M. Taguchi, Plasma Phys. Controlled Fusion 30, 1897 (1988)]. The obtained analytic expression for this flow, which can be used for general axisymmetric toroidal plasmas, agrees quite well with the recently calculated numerical results by Parker and Catto [Plasma Phys. Controlled Fusion 54, 085011 (2012)] in the full range of aspect ratio.

  15. The Proactive International Dimension and the Breakdown of Authoritarian Regimes

    OpenAIRE

    Castaldo, Antonino

    2016-01-01

    There is international consensus among scholars that democratic transitions are multicausal processes in which both internal and international variables are involved (Pridham 1991, 1995; Whitehead 1996; Schmitter 1996; Linz and Stepan 1996; Carothers 1999; Morlino and Magen 2008; Grilli di Cortona 2009). This chapter is limited, on the one hand, to the dependent variable consisting solely of the crisis/breakdown/transformation of non-democratic regimes in the Third Wave o...

  16. A Markov Switching Regime Model of Malaysia Property Cycle

    OpenAIRE

    Abdul M. Beksin; Bawa C Abdullahi

    2011-01-01

    Problem statement: Non-linear models such as the Markov Switching regime (MS) method of modelling business cycles, in principle can be used to model property cyle. Approach: The MS model can distinguish property cycle in recession and expansion phases and is sufficiently flexible to allow different relationships to apply over these phases. In this study, the Malaysian property cycle is modelled using a MS model. Results: This technique can be used to simultaneously estimate the data generatin...

  17. The relevance of universal jurisdiction in the complementarity regime

    OpenAIRE

    2012-01-01

    This study examines the relevance universal jurisdiction can have in the ICC complementarity regime. It argues that universal jurisdiction is an underdeveloped principle for exercising jurisdiction, and that the shortcomings of the principle therefore provide it to be exercised with restraint. However, this study also argues that there is a place for universal jurisdiction in those situations where the jurisdiction of the ICC leaves an impunity gap.

  18. The East Asian welfare regime: reality or fiction

    OpenAIRE

    Sarah Kuypers

    2014-01-01

    Recently the debate on the existence of a homogeneous East Asian welfare regime gained prominence because the region is experiencing changes in the fundamentals of its welfare system. Although the majority of the literature builds upon the assumption that there is indeed a fourth welfare type in the region, few empirically investigate whether these countries could formally be regarded as actual ‘Confucian’, ‘productivist’ or ‘developmental’ welfare states. In a detailed, but yet encompassing,...

  19. Newly discovered landscape traps produce regime shifts in wet forests

    OpenAIRE

    Lindenmayer, David B; Hobbs, Richard J; Gene E Likens; Krebs, Charles J.; Banks, Samuel C.

    2011-01-01

    We describe the “landscape trap” concept, whereby entire landscapes are shifted into, and then maintained (trapped) in, a highly compromised structural and functional state as the result of multiple temporal and spatial feedbacks between human and natural disturbance regimes. The landscape trap concept builds on ideas like stable alternative states and other relevant concepts, but it substantively expands the conceptual thinking in a number of unique ways. In this paper, we (i) review the lit...

  20. Regime-based forecast performance during WFIP 1

    Science.gov (United States)

    Freedman, J. M.; Zack, J. W.; Manobianco, J.; Beaucage, P.; Rojowsky, K.

    2015-12-01

    The principal objectives of the first Wind Forecast Improvement Project (WFIP 1) were to improve short-term (0 - 6 hr) wind power forecasts through the assimilation of targeted remote sensing and surface observations with an enhanced model ensemble forcast system. The WFIP 1 field deployment/modeling campaign in the Southern Study Area (SSA--encompassing most of central and western Texas) ran from August 2011 through Septembe 2012. This ensured observational data and model output for all representative weather regimes affecting the SSA. Cold and warm season regimes featured synoptic-scale, convective, and low-level jet (LLJ) phenomena that are responsible for the favorable wind resource in the SSA, and also posed a challenge for assigning specific explanations for the observed forecast improvements (e.g. additional observations, model improvements, or a combination of both). LLJs produced hourly capacity factors exceeding 80% in aggregated wind farm power production, while synoptic-scale systems were responsible for the largest ramp events observed during WFIP 1. Accurately forecasting convective phenomena (such as outflow boundaries) during WFIP 1 was at times problematic. Here, we present regime-based and phenomenological-related forecast performance results for WFIP 1. These performance metrics suggest future research pathways that will facilitate improvements in operational wind power forecasts.

  1. On the Fast Magnetic Rotator Regime of Stellar Winds

    CERN Document Server

    Johnstone, C P

    2016-01-01

    Aims: We study the acceleration of the stellar winds of rapidly rotating low mass stars and the transition between the slow magnetic rotator and fast magnetic rotator regimes. We aim to understand the properties of stellar winds in the fast magnetic rotator regime and the effects of magneto-centrifugal forces on wind speeds and mass loss rates. Methods: We extend the solar wind model of Johnstone et al. (2015b) to 1D magnetohydrodynamic (MHD) simulations of the winds of rotating stars. We test two assumptions for how to scale the wind temperature to other stars and assume the mass loss rate scales as Mdot ~ Rstar^2 OmegaStar^1.33 Mstar^-3.36, in the unsaturated regime, as estimated by Johnstone et al. (2015a). Results: For 1.0 Msun stars, the winds can be accelerated to several thousand km/s, and the effects of magneto-centrifugal forces are much weaker for lower mass stars. We find that the different assumptions for how to scale the wind temperature to other stars lead to significantly different mass loss ra...

  2. Unsustainable Groundwater Exploitation and Stochastic Regime Shifts: Converging Management Constraints

    Science.gov (United States)

    Rao, Suresh; Park, Jeryang

    2014-05-01

    Increasing water security concerns arise from projected increases in competing freshwater demands, resulting from rapid urbanization, growing affluent population, and the need for increased production of food and bio-energy. These global trends in concert with the convergence of three groups of threats are likely to exacerbate freshwater security issues: (1) increasing dependency on effectively non-renewable groundwater ("peak water"); (2) increasing groundwater quality impairment("land-use intensification") from larger contaminant loads delivered from the vadose zone and surface water; and (3) increasing uncertainties in groundwater demand/supply from climate change ("stochastic risks"). Here, we present a conceptual framework for exploring water security threats, with a consideration of aquifers as complex hydrological systems with two stable states. Regime shifts in groundwater pumping -- from "sufficient" to "insufficient" -- result from changes in both internal system dynamics and external forcing from stochastic divers (non-stationary demands, hydro-climatic patterns). Examples from recent related work, in groundwater and surface water systems and ecosystems, are briefly reviewed as a prelude to presentation of model simulations of hypothetical scenarios of regime-shifts (tipping points) involving groundwater quantity and quality constraints. In addition to three types of widely recognized tipping points, we introduce a new type, stochastic tipping, that contributes to unexpected, undesirable regime shifts, resulting in inability to meet groundwater pumping needs, even when the perceived precariousness is small and the system is far from bifurcation point (deterministic tipping). Implications to sustainable groundwater management are discussed.

  3. Regime shifts, resilience and recovery of a cod stock

    DEFF Research Database (Denmark)

    Lindegren, Martin; Diekmann, Rabea; Möllmann, Christian

    2010-01-01

    In the North and Baltic seas Atlantic cod Gadus morhua stocks collapsed as part or one of the major factors inducing large-scale ecosystem regime shifts. Determining the relative contribution of overfishing and climate variability in causing these shifts has proven difficult. While facing similar...... of the local cod stock to environmental change. The recovery and healthy condition of the Sound cod stock illustrate the need for adaptive marine management strategies that maximize ecosystem resilience....... and development of the Sound ecosystem, specifically testing for the occurrence of regime shifts and their potential drivers. By comparing the ecosystem development of the Sound with the neighbouring North and Baltic seas, we were able to demonstrate the positive effect of the trawl fishing ban on the resilience......In the North and Baltic seas Atlantic cod Gadus morhua stocks collapsed as part or one of the major factors inducing large-scale ecosystem regime shifts. Determining the relative contribution of overfishing and climate variability in causing these shifts has proven difficult. While facing similar...

  4. Kolmogorov and scalar spectral regimes in numerical turbulence

    Science.gov (United States)

    Kerr, R. M.

    1985-01-01

    Velocity and passive-scalar spectra for turbulent fields generated by a forced three-dimensional simulation and Taylormicroscale Reynolds numbers up to 83 are shown to have distinct spectral regimes, including a Kolmogorov inertial subrange. Both one- and three-dimensional spectra are shown for comparison with experiment and theory, respectively. When normalized by the Kolmogorov dissipation scales velocity spectra collapse to a single curve and a high-wavenumber bulge is seen. The bulge leads to an artificially high Kolmogorov constant, but is consistent with recent measurements of the velocity spectrum in the dissipation regime and the velocity-derivative skewness. Scalar spectra, when normalized by the Oboukov-Corrsin scales, collapse to curves which depend only on Prandtl number and show a universal inertial-convective subrange, independent of Prandtl number. When normalized by the Batchelor scales, the scalar spectra show a universal dissipation regime which is independent of Prandtl numbers from 0.1 to 1.0. The time development of velocity spectra is illustrated by energy-transfer spectra in which distinct pulses propagate to high wavenumbers.

  5. Idiosyncratic responses of high Arctic plants to changing snow regimes.

    Science.gov (United States)

    Rumpf, Sabine B; Semenchuk, Philipp R; Dullinger, Stefan; Cooper, Elisabeth J

    2014-01-01

    The Arctic is one of the ecosystems most affected by climate change; in particular, winter temperatures and precipitation are predicted to increase with consequent changes to snow cover depth and duration. Whether the snow-free period will be shortened or prolonged depends on the extent and temporal patterns of the temperature and precipitation rise; resulting changes will likely affect plant growth with cascading effects throughout the ecosystem. We experimentally manipulated snow regimes using snow fences and shoveling and assessed aboveground size of eight common high arctic plant species weekly throughout the summer. We demonstrated that plant growth responded to snow regime, and that air temperature sum during the snow free period was the best predictor for plant size. The majority of our studied species showed periodic growth; increases in plant size stopped after certain cumulative temperatures were obtained. Plants in early snow-free treatments without additional spring warming were smaller than controls. Response to deeper snow with later melt-out varied between species and categorizing responses by growth forms or habitat associations did not reveal generic trends. We therefore stress the importance of examining responses at the species level, since generalized predictions of aboveground growth responses to changing snow regimes cannot be made.

  6. Idiosyncratic responses of high Arctic plants to changing snow regimes.

    Directory of Open Access Journals (Sweden)

    Sabine B Rumpf

    Full Text Available The Arctic is one of the ecosystems most affected by climate change; in particular, winter temperatures and precipitation are predicted to increase with consequent changes to snow cover depth and duration. Whether the snow-free period will be shortened or prolonged depends on the extent and temporal patterns of the temperature and precipitation rise; resulting changes will likely affect plant growth with cascading effects throughout the ecosystem. We experimentally manipulated snow regimes using snow fences and shoveling and assessed aboveground size of eight common high arctic plant species weekly throughout the summer. We demonstrated that plant growth responded to snow regime, and that air temperature sum during the snow free period was the best predictor for plant size. The majority of our studied species showed periodic growth; increases in plant size stopped after certain cumulative temperatures were obtained. Plants in early snow-free treatments without additional spring warming were smaller than controls. Response to deeper snow with later melt-out varied between species and categorizing responses by growth forms or habitat associations did not reveal generic trends. We therefore stress the importance of examining responses at the species level, since generalized predictions of aboveground growth responses to changing snow regimes cannot be made.

  7. Socioecological regime shifts in the setting of complex social interactions

    Science.gov (United States)

    Sugiarto, Hendrik Santoso; Chung, Ning Ning; Lai, Choy Heng; Chew, Lock Yue

    2015-06-01

    The coupling between social and ecological system has become more ubiquitous and predominant in the current era. The strong interaction between these systems can bring about regime shifts which in the extreme can lead to the collapse of social cooperation and the extinction of ecological resources. In this paper, we study the occurrence of such regime shifts in the context of a coupled social-ecological system where social cooperation is established by means of sanction that punishes local selfish act and promotes norms that prescribe nonexcessive resource extraction. In particular, we investigate the role of social networks on social-ecological regimes shift and the corresponding hysteresis effects caused by the local ostracism mechanism under different social and ecological parameters. Our results show that a lowering of network degree reduces the hysteresis effect and also alters the tipping point, which is duly verified by our numerical results and analytical estimation. Interestingly, the hysteresis effect is found to be stronger in scale-free network in comparison with random network even when both networks have the same average degree. These results provide deeper insights into the resilience of these systems, and can have important implications on the management of coupled social-ecological systems with complex social interactions.

  8. Immunological responses elicited by different infection regimes with Strongyloides ratti.

    Directory of Open Access Journals (Sweden)

    Steve Paterson

    Full Text Available Nematode infections are a ubiquitous feature of vertebrate life. In nature, such nematode infections are acquired by continued exposure to infective stages over a prolonged period of time. By contrast, experimental laboratory infections are typically induced by the administration of a single (and often large dose of infective stages. Previous work has shown that the size of an infection dose can have significant effects on anti-nematode immune responses. Here we investigated the effect of different infection regimes of Strongyloides ratti, comparing single and repeated dose infections, on the host immune response that was elicited. We considered and compared infections of the same size, but administered in different ways. We considered infection size in two ways: the maximum dose of worms administered and the cumulative worm exposure time. We found that both infection regimes resulted in Th2-type immune response, characterised by IL4 and IL13 produced by S. ratti stimulated mesenteric lymph node cells, anti-S. ratti IgG(1 and intestinal rat mast cell protease II (RMCPII production. We observed some small quantitative immunological differences between different infection regimes, in which the concentration of IL4, IL13, anti-S. ratti IgG(1 and IgG(2a and RMCPII were affected. However, these differences were quantitatively relatively modest compared with the temporal dynamics of the anti-S. ratti immune response as a whole.

  9. Ecological forecasting in the presence of abrupt regime shifts

    Science.gov (United States)

    Dippner, Joachim W.; Kröncke, Ingrid

    2015-10-01

    Regime shifts may cause an intrinsic decrease in the potential predictability of marine ecosystems. In such cases, forecasts of biological variables fail. To improve prediction of long-term variability in environmental variables, we constructed a multivariate climate index and applied it to forecast ecological time series. The concept is demonstrated herein using climate and macrozoobenthos data from the southern North Sea. Special emphasis is given to the influence of selection of length of fitting period to the quality of forecast skill especially in the presence of regime shifts. Our results indicate that the performance of multivariate predictors in biological forecasts is much better than that of single large-scale climate indices, especially in the presence of regime shifts. The approach used to develop the index is generally applicable to all geographical regions in the world and to all areas of marine biology, from the species level up to biodiversity. Such forecasts are of vital interest for practical aspects of the sustainable management of marine ecosystems and the conservation of ecosystem goods and services.

  10. He-Accreting WDs: accretion regimes and final outcomes

    CERN Document Server

    Piersanti, L; Yungelson, L R

    2014-01-01

    The behaviour of carbon-oxygen white dwarfs (WDs) subject to direct helium accretion is extensively studied. We aim to analyze the thermal response of the accreting WD to mass deposition at different time scales. The analysis has been performed for initial WDs masses and accretion rates in the range (0.60 - 1.02) Msun and 1.e-9 - 1.e-5 Msun/yr, respectively. Thermal regimes in the parameters space M_{WD} - dot{M}_{He}, leading to formation of red-giant-like structure, steady burning of He, mild, strong and dynamical flashes have been identified and the transition between those regimes has been studied in detail. In particular, the physical properties of WDs experiencing the He-flash accretion regime have been investigated in order to determine the mass retention efficiency as a function of the accretor total mass and accretion rate. We also discuss to what extent the building-up of a He-rich layer via H-burning could be described according to the behaviour of models accreting He-rich matter directly. Polynomi...

  11. Intermittency of rheological regimes in uniform liquid-granular flows.

    Science.gov (United States)

    Armanini, Aronne; Larcher, Michele; Fraccarollo, Luigi

    2009-05-01

    We present a detailed analysis of a free surface-saturated liquid-granular mixture flowing over a static loose bed of grains, where the coexistence of layers dominated by collisional and frictional interactions among particles was observed. Kinetic theory was applied to the flow described above and it proved suitable for describing a realistic behavior of the collisional layers, although it failed to interpret the regions of the flow domain dominated by the frictional contacts. The paper provides a conceptual scheme with which to overcome this problem by focusing on the mechanisms governing the transition from the frictional to the collisional regime. In particular we observed that in highly concentrated flows the transition layer exhibits a typical intermittency of the dominating rheological regime, switching alternately from the frictional to the collisional one. By filtering the velocity signal, we introduced an intermittency function that made it possible to extend the validity of the equations derived from dense gas analogy, typical of the collisional regimes, also in the intermittent phase of the flow. Owing to the small values of the Stokes number, in the application of the kinetic theory we accounted for the possible variation of the elastic restitution coefficient along the flow depth. PMID:19518448

  12. British Columbia's new coalbed methane royalty regime

    Energy Technology Data Exchange (ETDEWEB)

    Molinski, D. [British Columbia Ministry of Energy and Mines, Victoria, BC (Canada). Energy and Minerals Div.

    2002-07-01

    The British Columbia Ministry of Energy and Mines is promoting the development of the coalbed methane (CBM) industry in the province in order to make CBM a viable and competitive investment option for industry. It is establishing a regulatory and fiscal regime for CBM development. Issues of concern regarding CBM development include water production, gas production rates, well numbers, and marginal economics. The features of the CBM royalty regime include a new producer cost of service allowance, the creation of a CBM royalty tax bank to collect excess PCOS allowances, and a royalty tax credit for wells drilled by the end of February, 2004. The marginal well adjustment factor threshold has been raised from 180 mcf per day to 600 mcf per day for CBM only. It was noted that royalties will probably not be payable for several years following the first commercial well because royalties are very depending on capital and operating costs, local infrastructure and price. Royalty regimes cannot save CBM from low gas prices, poor resources or economics. 2 figs.

  13. Spray structure as generated under homogeneous flash boiling nucleation regime

    International Nuclear Information System (INIS)

    We show the effect of the initial pressure and temperature on the spatial distribution of droplets size and their velocity profile inside a spray cloud that is generated by a flash boiling mechanism under homogeneous nucleation regime. We used TSI's Phase Doppler Particle Analyzer (PDPA) to characterize the spray. We conclude that the homogeneous nucleation process is strongly affected by the initial liquid temperature while the initial pressure has only a minor effect. The spray shape is not affected by temperature or pressure under homogeneous nucleation regime. We noted that the only visible effect is in the spray opacity. Finally, homogeneous nucleation may be easily achieved by using a simple atomizer construction, and thus is potentially suitable for fuel injection systems in combustors and engines. - Highlights: • We study the characteristics of a spray that is generated by a flash boiling process. • In this study, the flash boiling process occurs under homogeneous nucleation regime. • We used Phase Doppler Particle Analyzer (PDPA) to characterize the spray. • The SMD has been found to be strongly affected by the initial liquid temperature. • Homogeneous nucleation may be easily achieved by using a simple atomizer unit

  14. Siberian Lena River hydrologic regime and recent change

    Science.gov (United States)

    Yang, Daqing; Kane, Douglas L.; Hinzman, Larry D.; Zhang, Xuebin; Zhang, Tingjun; Ye, Hengchun

    2002-12-01

    The long-term (1935-1999) monthly records of temperature, precipitation, stream flow, river ice thickness, and active layer depth have been analyzed in this study to examine Lena River hydrologic regime and recent change. Remarkable hydrologic changes have been identified in this study. During the cold season (October-April), significant increases (25-90%) in stream flow and decrease in river ice thickness have been found due to warming in Siberia. In the snowmelt period (May-June), strong warming in spring leads to an advance of snowmelt season into late May and results in a lower daily maximum discharge in June. During summer months (July-September) the changes in stream flow hydrology are less significant in comparison to those for winter and spring seasons. A slight stream flow increase is discovered for both July and August, mainly owing to precipitation increase in May and June. Discharge in September has a slight downward trend due to precipitation decrease and temperature increase in August. The magnitudes of changes in stream flow and river ice thickness identified in this study are large enough to alter the hydrologic regime. Investigation into the hydrologic response of the Lena River to climate change and variation reveals strong linkages of stream flow with temperature and precipitation. We therefore believe that Lena River hydrologic regime changes are mainly the consequence of recent climate warming over Siberia and also closely related to changes in permafrost condition.

  15. Perspective: Single polymer mechanics across the force regimes

    Science.gov (United States)

    Saleh, Omar A.

    2015-05-01

    I review theoretical and experimental results on the force-extension response of single polymers, with a focus on scaling pictures of low-force elastic regimes, and recent measurements of synthetic and biological chains that explore those regimes. The mechanical response of single polymers is an old theoretical problem whose exploration was instigated by the curious thermomechanical behavior of rubber. Up until the 1990s, the main utility of those calculations was to explain bulk material mechanics. However, in that decade, it became possible to directly test the calculations through high-precision single-chain stretching experiments (i.e., force spectroscopy). I present five major single-chain elasticity models, including scaling results based on blob-chain models, along with analytic results based on linear response theory, and those based on freely jointed chain or worm-like chain structure. Each model is discussed in terms of the regime of force for which it holds, along with the status of its rigorous assessment with experiment. Finally, I show how the experiments can provide new insight into polymer structure itself, with particular emphasis on polyelectrolytes.

  16. Global impacts of the 1980s regime shift.

    Science.gov (United States)

    Reid, Philip C; Hari, Renata E; Beaugrand, Grégory; Livingstone, David M; Marty, Christoph; Straile, Dietmar; Barichivich, Jonathan; Goberville, Eric; Adrian, Rita; Aono, Yasuyuki; Brown, Ross; Foster, James; Groisman, Pavel; Hélaouët, Pierre; Hsu, Huang-Hsiung; Kirby, Richard; Knight, Jeff; Kraberg, Alexandra; Li, Jianping; Lo, Tzu-Ting; Myneni, Ranga B; North, Ryan P; Pounds, J Alan; Sparks, Tim; Stübi, René; Tian, Yongjun; Wiltshire, Karen H; Xiao, Dong; Zhu, Zaichun

    2016-02-01

    Despite evidence from a number of Earth systems that abrupt temporal changes known as regime shifts are important, their nature, scale and mechanisms remain poorly documented and understood. Applying principal component analysis, change-point analysis and a sequential t-test analysis of regime shifts to 72 time series, we confirm that the 1980s regime shift represented a major change in the Earth's biophysical systems from the upper atmosphere to the depths of the ocean and from the Arctic to the Antarctic, and occurred at slightly different times around the world. Using historical climate model simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) and statistical modelling of historical temperatures, we then demonstrate that this event was triggered by rapid global warming from anthropogenic plus natural forcing, the latter associated with the recovery from the El Chichón volcanic eruption. The shift in temperature that occurred at this time is hypothesized as the main forcing for a cascade of abrupt environmental changes. Within the context of the last century or more, the 1980s event was unique in terms of its global scope and scale; our observed consequences imply that if unavoidable natural events such as major volcanic eruptions interact with anthropogenic warming unforeseen multiplier effects may occur. PMID:26598217

  17. Soil water regime under homogeneous eucalyptus and pine forests

    International Nuclear Information System (INIS)

    Measurement of precipitation and monthly soil water content during two consecutive years, in 6-year old plantations of eucalypt and pine, and also in an open plot containing natural herbaceous vegetation, were used to compare the soil water regime of these vegetation covers. Precipitation was measured in the open plot with a recording and a non-recording rain gage. Soil water was assessed by the neutron scattering technique to a depth of 1,80 meters. Results indicate that there was, in general, water available in the soil over the entire period of study in all three vegetation conditions. The annual range of soil water in eucalypt, pine, and in natural herbaceous vegetation was essentially similar. The analysis of the average soil water regime showed that the soil under herbaceous vegetation was, generally, more umid than the soil under eucalypt and pine during the period of soil water recharge (September through February); during the period of soil water depletion, the opposite was true. Collectively, the results permit the conclusion that there were no adverse effects on the soil water regime which could be ascribed to reflorestation with eucalypt or pine, as compared with that observed for the natural herbaceous vegetation

  18. Production Regimes for Self-Interacting Dark Matter

    CERN Document Server

    Bernal, Nicolas; Garcia-Cely, Camilo; Hambye, Thomas; Zaldivar, Bryan

    2015-01-01

    In the context of Self-Interacting Dark Matter as a solution for the small-scale structure problems, we consider the possibility that Dark Matter could have been produced without being in thermal equilibrium with the Standard Model bath. We discuss one by one the following various dark matter production regimes of this kind: freeze-in, reannihilation and dark freeze-out. We exemplify how these mechanisms work in the context of the particularly simple Hidden Vector Dark Matter model. In contrast to scenarios where there is thermal equilibrium with the Standard Model bath, we find two regimes which can easily satisfy all the laboratory and cosmological constraints. These are dark freeze-out with 3-to-2 annihilations and freeze-in via a light mediator. In the first regime, different temperatures in the visible and the Dark Matter sectors allow us to avoid the constraints coming from cosmic structure formation as well as the use of non-perturbative couplings to reproduce the observed relic density. For the second...

  19. Interannual variability of snow and fluvial regimes in Andorra

    Science.gov (United States)

    Pesado, Cristina; Riba, Sergi; Pons, Marc; Lopez-Moreno, Juan Ignacio

    2016-04-01

    Highlands in Andorra are snow-dominated areas during all the winter and most of the spring season. Interannual snow variability in these areas has a strong and straight influence on the amount and seasonality of river regimes at the bottom of the valley where most of the population and water requirements are concentrated. The present study analyzes the temporal and spatial variability of the fluvial regimes in Andorra and seeks to understand the interplay of different topographic and climatic variables on this variability. For example, in mountainous regions temperature determines the state of precipitation and this state can significantly affect runoff formation. The interannual temporal and spatial variability of temperatures, pluviometry and different snow indices such as snow heights and days with snow on the ground has been studied for the last decade and correlated with the fluvial dynamics and its variability using discharge measurements. This study focus especially in the assessment of the role of snow and its seasonality in the fluvial regime dynamics and the influence in the torrential flows and flood hazard. Flood hazard, force to take protection measures, which need information about flood frequency and magnitude. For this, flow instrumental series are used, but usually they do not consider phenomena like snowmelt. This study contributes intends to better understand the interplay between snow and fluvial dynamics and improve the assessment of the availability of water resources as well as the requirements in terms of protection measures.

  20. Fire regimes of quaking aspen in the Mountain West

    Science.gov (United States)

    Shinneman, Douglas J.; Baker, William L.; Rogers, Paul C.; Kulakowski, Dominik

    2013-01-01

    Quaking aspen (Populus tremuloides Michx.) is the most widespread tree species in North America, and it is found throughout much of the Mountain West (MW) across a broad range of bioclimatic regions. Aspen typically regenerates asexually and prolifically after fire, and due to its seral status in many western conifer forests, aspen is often considered dependent upon disturbance for persistence. In many landscapes, historical evidence for post-fire aspen establishment is clear, and following extended fire-free periods senescing or declining aspen overstories sometimes lack adequate regeneration and are succeeding to conifers. However, aspen also forms relatively stable stands that contain little or no evidence of historical fire. In fact, aspen woodlands range from highly fire-dependent, seral communities to relatively stable, self-replacing, non-seral communities that do not require fire for persistence. Given the broad geographic distribution of aspen, fire regimes in these forests likely co-vary spatially with changing community composition, landscape setting, and climate, and temporally with land use and climate – but relatively few studies have explicitly focused on these important spatiotemporal variations. Here we reviewed the literature to summarize aspen fire regimes in the western US and highlight knowledge gaps. We found that only about one-fourth of the 46 research papers assessed for this review could be considered fire history studies (in which mean fire intervals were calculated), and all but one of these were based primarily on data from fire-scarred conifers. Nearly half of the studies reported at least some evidence of persistent aspen in the absence of fire. We also found that large portions of the MW have had little or no aspen fire history research. As a result of this review, we put forth a classification framework for aspen that is defined by key fire regime parameters (fire severity and probability), and that reflects underlying biophysical

  1. Fire regime in a Mexican forest under indigenous resource management.

    Science.gov (United States)

    Fulé, Peter Z; Ramos-Gómez, Mauro; Cortés-Montaño, Citlali; Miller, Andrew M

    2011-04-01

    The Rarámuri (Tarahumara) people live in the mountains and canyons of the Sierra Madre Occidental of Chihuahua, Mexico. They base their subsistence on multiple-use strategies of their natural resources, including agriculture, pastoralism, and harvesting of native plants and wildlife. Pino Gordo is a Rarámuri settlement in a remote location where the forest has not been commercially logged. We reconstructed the forest fire regime from fire-scarred trees, measured the structure of the never-logged forest, and interviewed community members about fire use. Fire occurrence was consistent throughout the 19th and 20th centuries up to our fire scar collection in 2004. This is the least interrupted surface-fire regime reported to date in North America. Studies from other relict sites such as nature reserves in Mexico or the USA have all shown some recent alterations associated with industrialized society. At Pino Gordo, fires recurred frequently at the three study sites, with a composite mean fire interval of 1.9 years (all fires) to 7.6 years (fires scarring 25% or more of samples). Per-sample fire intervals averaged 10-14 years at the three sites. Approximately two-thirds of fires burned in the season of cambial dormancy, probably during the pre-monsoonal drought. Forests were dominated by pines and contained many large living trees and snags, in contrast to two nearby similar forests that have been logged. Community residents reported using fire for many purposes, consistent with previous literature on fire use by indigenous people. Pino Gordo is a valuable example of a continuing frequent-fire regime in a never-harvested forest. The Rarámuri people have actively conserved this forest through their traditional livelihood and management techniques, as opposed to logging the forest, and have also facilitated the fire regime by burning. The data contribute to a better understanding of the interactions of humans who live in pine forests and the fire regimes of these

  2. Hydrological regime modifications induced by climate change in Mediterranean area

    Science.gov (United States)

    Pumo, Dario; Caracciolo, Domenico; Viola, Francesco; Valerio Noto, Leonardo

    2015-04-01

    The knowledge of river flow regimes has a capital importance for a variety of practical applications, in water resource management, including optimal and sustainable use. Hydrological regime is highly dependent on climatic factors, among which the most important is surely the precipitation, in terms of frequency, seasonal distribution and intensity of rainfall events. The streamflow frequency regime of river basins are often summarized by flow duration curves (FDCs), that offer a simple and comprehensive graphical view of the overall historical variability associated with streamflow, and characterize the ability of the basin to provide flows of various magnitudes. Climate change is likely to lead shifts in the hydrological regime, and, consequently, in the FDCs. Staring from this premise, the primary objective of the present study is to explore the effects of potential climate changes on the hydrological regime of some small Mediterranean basins. To this aim it is here used a recent hydrological model, the ModABa model (MODel for Annual flow duration curves assessment in ephemeral small BAsins), for the probabilistic characterization of the daily streamflows in small catchments. The model has been calibrated and successively validated in a unique small catchment, where it has shown a satisfactory accuracy in reproducing the empirical FDC starting from easily derivable parameters arising from basic ecohydrological knowledge of the basin and commonly available climatic data such as daily precipitation and temperatures. Thus, this work also represents a first attempt to apply the ModABa to basins different from that used for its preliminary design in order to testing its generality. Different case studies are selected within the Sicily region; the model is first calibrated at the sites and then forced by future climatic scenarios, highlighting the principal differences emerging from the current scenario and future FDCs. The future climate scenarios are generated using

  3. Human impacts on river ice regime in the Carpathian Basin

    Science.gov (United States)

    Takács, Katalin; Nagy, Balázs; Kern, Zoltán

    2014-05-01

    River ice is a very important component of the cryosphere, and is especially sensitive to climatic variability. Historical records of appearance or disappearance and timing of ice phenomena are useful indicators for past climatic variations (Williams, 1970). Long-term observations of river ice freeze-up and break-up dates are available for many rivers in the temperate or cold region to detect and analyze the effects of climate change on river ice regime. The ice regime of natural rivers is influenced by climatic, hydrological and morphological factors. Regular ice phenomena observation mostly dates back to the 19th century. During this long-term observation period, the human interventions affecting the hydrological and morphological factors have become more and more intensive (Beltaos and Prowse, 2009). The anthropogenic effects, such as river regulation, hydropower use or water pollution causes different changes in river ice regime (Ashton, 1986). To decrease the occurrence of floods and control the water discharge, nowadays most of the rivers are regulated. River regulation changes the morphological parameters of the river bed: the aim is to create solid and equable bed size and stream gradient to prevent river ice congestion. For the satisfaction of increasing water demands hydropower is also used. River damming results a condition like a lake upstream to the barrage; the flow velocity and the turbulence are low, so this might be favourable for river ice appearance and freeze-up (Starosolsky, 1990). Water pollution affects ice regime in two ways; certain water contaminants change the physical characteristics of the water, e.g. lessens the freezing point of the water. Moreover the thermal stress effect of industrial cooling water and communal wastewater is also important; in winter these water sources are usually warmer, than the water body of the river. These interventions result different changes in the characteristic features of river ice regime. Selected

  4. Crop based climate regimes for energy saving in greenhouse cultivation

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, O.

    2003-06-16

    Sustainability is one of the major aims in greenhouse horticulture. According to agreements between the Dutch grower association and the government, energy consumption and the use of chemical biocides have to be reduced. More advanced greenhouse technique is being developed to reach the target to decrease the energy efficiency-index by 65% between 1980 and 2010. However, this could also be achieved with existing technology by using more advanced climate regimes. The present thesis aimed at that, through designing and analysing climate regimes while employing existing climate control possibilities. Theoretical temperature and humidity regimes were designed to decrease energy consumption and a photosynthesis maximisation procedure was implemented to maximise growth. The basis for a crop gross photosynthesis model for control purposes was created. Crop photosynthesis models were evaluated at conditions expected to occur with more sustainable climate regimes. It was shown with experimental evidence that theoretical assumptions on the temperature - CO2 effects in a crop that are based on theoretically models scaling up leaf photosynthesis to the crop level are valid and that simplified existing models could be applied up to 28C. With higher temperatures new designs are needed and this can probably be achieved with an improved stomata-resistance model. The well known temperature integration principle was modified with two nested time-frames (24-hour and six days) and a temperature dose-response function. In a year round tomato cultivation, energy consumption was predicted to decrease with up to 9 % compared to regular temperature integration. The potential for energy saving with temperature integration is limited by humidity control when as usual fixed set points are maintained, because it counteracts temperature integration. Vents open at lower temperatures and heating is switched on at higher temperatures than required for optimal effects of temperature integration. A

  5. China and Nuclear Non-Proliferation Regime, 1964-1989

    International Nuclear Information System (INIS)

    The invention of nuclear weapons opened a new era for the history of human weaponry and warfare, and also reshaped international relations. As a consequence, a worldwide consensus has been gradually reached due to the destructive nature of nuclear weapons: since a world with nuclear weapons is extremely dangerous, all human beings must make coordinated effort to eliminate nuclear weapons completely. To achieve this goal, which is unrealistic for the time being, a step must be taken now to stop the proliferation of nuclear weapons and its technology. China became a nuclear power in 1964, and ever since, China’s attitude with the nuclear non-proliferation regime has been closely linking China’s core strategic interests with the stability of the world. The relationship between China and the nuclear non-proliferation regime is expounded in two stages during the Cold War era. From the early 1960s to late 1970s, China criticized the nuclear non-proliferation idea by arguing for a complete elimination of nuclear weapons by all nuclear powers. China criticized the Partial Test Ban Treaty (PTBT) and the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), when it believed that both treaties aimed only for the existing nuclear powers to monopolize nuclear technology and power. Since the reforms began in the opening-up era in the 1980s, China became actively involved in participation in the nuclear non-proliferation regime, which not only changed China’s national identity but also readjusted China’s vision about its own national interest and the global security. China affirmed its rejection to nuclear proliferation and began to involve partly in nuclear non-proliferation regime. China joined the International Atomic Energy Agency in 1984. In 1988, China signed an agreement with the IAEA for the application of safeguards, and voluntarily placed its civilian nuclear facilities under the IAEA safeguards. However China maintained its resistance to the NPT. This paper

  6. Correlation Between Transient Regime and Steady-State Regime on Creep Crack Growth Behavior of Grade 91 Steel

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Young; Ekaputra, I. M. W.; Kim, Seon Jin [Pukyong National Univ., Busan (Korea, Republic of); Kim, Woo Gon; Kim, Eung Seon [KAERI, Daejeong (Korea, Republic of)

    2015-12-15

    A correlation between the transient regime and steady state regime on the creep crack growth (CCG) for Grade 91 steel, which is used as the structural material for the Gen-IV reactor systems, was investigated. A series of CCG tests were performed using 1/2' CT specimens under a constant applied load and at a constant temperature of 600 °C. The CCG rates for the transient and steady state regimes were obtained in terms of C* parameter. The transient CCG rate had a close correlation with the steady-state CCG rate, as the slope of the transient CCG data was very similar to that of the steady state data. The transient rate was slower by 5.6 times as compared to the steady state rate. It can be inferred that the steady state CCG rate, which is required for long-time tests, can be predicted from the transient CCG rate obtained from short-time tests.

  7. General Considerations about Matrimonial Regime under the Provisions of the New Romanian Civil Code

    Directory of Open Access Journals (Sweden)

    Nadia Cerasela ANITEI

    2011-12-01

    Full Text Available The provisions of art. 312 of the Civil Code establish: a legal system, that is the community property regime and two types of conventional regimes: the regime of separation of goods and the regime of conventional community (the latter includes conventional derogation from community property regime.Legal matrimonial regime includes assets acquired by each spouse during marriage, except property required by law, which represents each spouse’s own assets.Community legal regime will apply in all situations in which prospective spouses opt for separation of property regime or the regime of conventional community.Separation of property regime is characterized by the fact that each of the spouses is the exclusive owner of their current assets and of those acquired alone after the dissolution of marriage, for the adoption of this regime the spouses being forced to draw up an inventory of movable property belonging to each one at the contracting of marriage.Conventional community regime is applicable when by matrimonial agreement, it derogates from the provisions on legal community regime, and the matrimonial convention concluded in this case can narrow or broaden the community of goods.

  8. The world's non-proliferation regime in time

    International Nuclear Information System (INIS)

    The idea for a treaty to prevent the spread of nuclear weapons to more countries was supported unanimously by the UN General Assembly in 1961. The NPT permits the P-5 to have nuclear weapons. All other NPT signatories are 'non-nuclear-weapon States' who are prohibited from acquiring nuclear weapons. To gain their signatures, the NPT promises assistance to them in the peaceful uses of nuclear energy and negotiations toward nuclear disarmament. Besides the P-5, the treaty now has 184 countries that have promised not to have nuclear weapons and that have agreed to accept inspections by the IAEA to verify that they are carrying out their promises. However, India, Pakistan, and Israel refused to join the treaty, and the Democratic People's Republic of Korea (North Korea) withdrew from it. Of these four countries, only India and Pakistan have tested nuclear weapons. Israel and North Korea are assumed to have them. The non-proliferation regime today includes much more than the NPT. The IAEA standards for inspection were the next most important element. The IAEA inspection requirements negotiated in the early 1970s were shown to be inadequate by Iraq's success in hiding its nuclear-weapon efforts before and during the Gulf War of 1991. The Additional Protocol of 1997 is slowly replacing these requirements, but, as of December 2004, was in effect in only 62 NPT member countries. The regime includes the agreements creating nuclear-weapon free zones in Africa, Latin America, Southeast Asia, the South Pacific, and Mongolia. The countries that formed these zones are also members of the NPT. The regime includes suggestions for standards and financial assistance plus requirements for physical protection of nuclear material from theft by terrorists or others. These efforts range from the Convention on Physical Protection of Nuclear Material, to the technical assistance provided by the IAEA and some countries, to the financial assistance offered by the G-8 and some other IAEA

  9. Technical efficiency under alternative environmental regulatory regimes: The case of Dutch horticulture

    NARCIS (Netherlands)

    Vlist, van der A.J.; Withagen, C.; Folmer, H.

    2007-01-01

    We consider the performance of small and medium sized enterprises in Dutch horticulture under different environmental policy regimes across time. We address the question whether technical performance differs under these alternative regulatory regimes to test Porter's hypothesis that stricter environ

  10. Technical efficiency under alternative environmental regulatory regimes : The case of Dutch horticulture

    NARCIS (Netherlands)

    van der Vlist, Arno J.; Withagen, Cees; Folmer, Henk

    2007-01-01

    We consider the performance of small and medium sized enterprises in Dutch horticulture under different environmental policy regimes across time. We address the question whether technical performance differs under these alternative regulatory regimes to test Porter's hypothesis that stricter environ

  11. Direct-contact condensation regime map for core makeup tank of passive reactors

    International Nuclear Information System (INIS)

    The condensation regime map in the core makeup tank of passive reactors is experimentally investigated. The condensation regimes identified through the experiments are divided into three distinct ones: sonic jet, subsonic jet, and steam cavity. The steam cavity regime is a unique regime of downward injection with the present geometry not previously observed in other experiments. The condensation regime map is constructed using Froude number and Jacob number. It turns out that the buoyancy force has a large influence on the regime transition because the regime map using the Froude number better fits data with different geometries than other dimensionless parameters. Simple correlations for the regime boundaries are proposed using the Froude number and the Jacob number

  12. A Safety-Case Regime for Commercial Human Spaceflight

    Science.gov (United States)

    Sgobba, T.; Trujillo, M.

    2012-01-01

    Currently the commercial human spaceflight community seems to be embracing the obsolete design principles of "fly-fix-fly", and betting on public acceptance of risks comparable to those of the early times of aviation industry. The nascent space tourism industry maintains that early safety regulations (apart public safety) would kill industry and that such regulations could be developed only later when substantial operational experience is gained. Truly, most of current commercial aviation safety regulations are based on prescriptive requirements (i.e. explicitly required design solution for an implicit goal), which have been incrementally developed over more than a half century of mass transportation by air, and cannot be in general directly applied to innovative systems. However modern complex safety-critical systems cannot risk catastrophic failures while their operational experience is being accumulated, for such reason they are developed through the so called safety-case regime. ESA is currently drafting a safety standard for its future human rated transportation systems that is based on such regime. Such standard can be easily tailored with few modifications and applied to the development of a sub-orbital commercial space vehicle. In any case, because the safety-case regime makes extensive use of generically formulated requirements, the support of skilled safety engineers fully integrated into the design team is required since the very beginning. Furthermore the safety certification team needs also to be experienced in the review of safety-case based designs. Finally a quantitative safety target needs to be included and verified as the ultimate "prove of goodness" of system design.

  13. Are there two regimes in strongly rotating turbulence?

    Science.gov (United States)

    Baqui, Yasir Bin; Davidson, P. A.; Ranjan, Avishek

    2016-04-01

    We describe numerical experiments of freely decaying, rapidly rotating turbulence in which the Rossby number varies from Ro = O(1) down to Ro ˜ 0.02. Our central premise is that there exists two distinct dynamical regimes; one for Ro > 0.3 → 0.4, which is typical of most laboratory experiments, and another corresponding to Ro 0.3 → 0.4 is reported in Baqui and Davidson ["A phenomenological theory of rotating turbulence," Phys. Fluids 27, 025107 (2015)] and is characterised by: (i) a growth of the parallel integral scale according to l|| ˜ l⊥Ωt; (ii) a dissipation law which is quite different from that predicted by weak-turbulence theories, specifically ɛ = βu3/l|| where the pre-factor β is a constant of order unity; and (iii) an inertial-range energy spectrum for both the parallel and perpendicular wavenumbers which scales as k-5/3, a scaling that has nothing to do with Kolmogorov's law in non-rotating turbulence. (Here, l|| is the integral length-scale parallel to the rotation vector Ω, l⊥ the integral length-scale perpendicular to Ω, u the integral scale velocity, and ɛ the viscous dissipation rate per unit mass.) By contrast, in the low-Ro regime, we find that l|| ˜ l⊥Ωt is replaced by l|| ˜ ut and there is no power-law scaling of the inertial range energy spectrum. While the dissipation law ɛ = βu3/l|| continues to hold at low Ro, at least approximately, the value of β now depends on Ro. It appears, therefore, that the dynamics of these two regimes are very different, and this may help explain why experimentalists and theoreticians sometimes present rather different interpretations of rotating turbulence.

  14. The superradiant instability regime of the spinning Kerr black hole

    OpenAIRE

    Hod, Shahar

    2016-01-01

    Spinning Kerr black holes are known to be superradiantly unstable to massive scalar perturbations. We here prove that the instability regime of the composed Kerr-black-hole-massive-scalar-field system is bounded from above by the dimensionless inequality $M\\mu < m \\cdot \\sqrt{{{2(1+\\gamma) (1-\\sqrt{1-\\gamma^2}) - \\gamma^2} \\over {4\\gamma^2}}}$, where $\\{\\mu,m\\}$ are respectively the proper mass and azimuthal harmonic index of the scalar field and $\\gamma\\equiv r_-/r_+$ is the dimensionless ra...

  15. Canada on course to introduce permissive assisted dying regime.

    Science.gov (United States)

    Schuklenk, Udo

    2016-08-01

    Canada's Supreme Court decided in February 2015 that the criminalisation of assisted dying in the country violates the country's citizens and residents constitutional rights. This paper reviews policy recommendations produced by a special expert advisory panel appointed by Canada's provinces and territories, where the responsibility for the provision of health care lies. It also reviews a similar document produced by a special federal parliamentary committee. Based on the review of these two milestone documents it is argued that a Canadian consensus seems to emerge that foreshadows a permissive regulatory regime in that country. PMID:27009981

  16. Variational Bayes for Regime-Switching Log-Normal Models

    Directory of Open Access Journals (Sweden)

    Hui Zhao

    2014-07-01

    Full Text Available The power of projection using divergence functions is a major theme in information geometry. One version of this is the variational Bayes (VB method. This paper looks at VB in the context of other projection-based methods in information geometry. It also describes how to apply VB to the regime-switching log-normal model and how it provides a computationally fast solution to quantify the uncertainty in the model specification. The results show that the method can recover exactly the model structure, gives the reasonable point estimates and is very computationally efficient. The potential problems of the method in quantifying the parameter uncertainty are discussed.

  17. Drainage vent systems: investigation and analysis of air pressure regime

    Energy Technology Data Exchange (ETDEWEB)

    Swaffield, J.A.; Jack, L.B. [Heriot-Watt University, Edinburgh (United Kingdom). Dept. of Building Engineering and Surveying

    1998-12-31

    Knowledge of the performance of building drainage vent systems and associated appliance trap seal loss and retention has developed in recent years due to extensive research into the generation and propagation of air pressure transients within drainage networks. This paper demonstrates how data gathered from experimental testing of several single stack systems, considering the influence of a wide range of parameters including stack diameter, roughness, height and applied water flow rate, can be used to provide generally applicable mathematical expressions which assist in determining the pressure regime present at critical points within such systems. (author)

  18. Crossflow and water banks in viscous dominant regimes of waterflooding

    DEFF Research Database (Denmark)

    Yuan, Hao; Zhang, Xuan; Shapiro, Alexander;

    2014-01-01

    profiles are more even and smoother in a communicating layer-cake reservoir than in a noncommunicating one. Water banks and transition zones may be observed. Analysis indicates that the phenomena are attributed to the enhanced crossflow due to large mobility ratios (water-oil). The mobility control......Understanding the crossflow in multilayered reservoirs is of great importance for designing mobility control methods for enhanced oil recovery. The authors reveal saturation profiles in stratified reservoirs to study the interlayer communication in the viscous dominant regime. The displacement...

  19. Defocusing regimes of nonlinear waves in media with negative dispersion

    DEFF Research Database (Denmark)

    Bergé, L.; Kuznetsov, E.A.; Juul Rasmussen, J.

    1996-01-01

    Defocusing regimes of quasimonochromatic waves governed by a nonlinear Schrodinger equation with mixed-sign dispersion are investigated. For a power-law nonlinearity, we show that localized solutions to this equation defined at the so-called critical dimension cannot collapse in finite time...... in the sense that their transverse (anomalously dispersing) and longitudinal (normally dispersing) extensions never vanish. Solutions defined at the supercritical dimension are proved to exhibit a nonvanishing mean longitudinal size, and cannot transversally collapse if they are assumed to shrink along each...

  20. Terahertz phase microscopy in the sub-wavelength regime

    Science.gov (United States)

    Yi, Minwoo; Lee, Kanghee; Song, Jin-Dong; Ahn, Jaewook

    2012-04-01

    Gouy phase shift is a well-known behavior that occurs when a propagating light is focused, but its behavior in the sub-wavelength confinement is not yet known. Here, we report the theoretical and experimental study of the aperture-size dependency of the Gouy phase shift in the sub-wavelength diffraction regime. In experiments carried out with laser-induced terahertz (THz) wave emission from various semiconductor apertures, we demonstrate the use of Guoy phase shit for sub-wavelength THz microscopy.

  1. Operating regimes of an unconventional radial pump stage

    Energy Technology Data Exchange (ETDEWEB)

    Gantar, T. [Turbomachinery Div., Envita d.o.o., Ljubljana (Slovenia); Sekavcnik, M. [Ljubljana Univ. (Slovenia). Faculty of Mechanical Engineering

    2007-06-15

    This paper presents some phenomena concerning the stability problem of the basic flow direction observed within the CFD analyses of an unconventional radial pump stage (RPS). In order to preclude defining the flow direction as a boundary condition, a closed hydraulic system was modelled to investigate the operating behaviour of the RPS and its energy characteristics. It was shown that the basic flow direction through the RPS is determined by the level of hydraulic losses within the closed hydraulic system. Combining the closed and open hydraulic system calculations, all possible operating regimes of the analysed RPS are presented by means of 4-quadrant chart. (orig.)

  2. Simulation of the Operation Regimes of a Welding Transformer

    Directory of Open Access Journals (Sweden)

    Lenuta Suciu

    2009-10-01

    Full Text Available The object of the paper is constituted by the simulation of the operation regimes of an electric transformer, using specialised simulation software, in order to determine the electromagnetic strains to which welding transformers are subjected to in the case of the faulty operation. The monitoring processes of the modern welding equipment impose the reduction of the risk of their breakdown, grace to the collection and processing of detailed information about the condition of the transformers with the help of specialised modelling software with finite element.

  3. Time-domain diagnostics in the picosecond regime

    International Nuclear Information System (INIS)

    The measurement of bunch length and longitudinal profile for microbunches of electrons and positrons in the ps and sub-ps regime will be a critical part of validating performance of proposed facilities. Data will be presented showing single-sweep streak camera results at σres ∼ 68 fs and projected synchroscan sweep resolution at σ ∼ 600 fs. Additionally, an rf cavity operating in a transverse magnetic mode has recently been shown to produce σres ∼ 280 fs when used with a low-emittance beam. The potential for dual-sweep streak work with σres < 1 ps on the fast axis is also described

  4. O regime de exigibilidade de caixa no IVA

    OpenAIRE

    Ferreira, Sónia Patrícia Duarte

    2011-01-01

    Mestrado em Contabilidade O Imposto sobre o Valor Acrescentado sucedeu ao imposto de transacções em 1986. Este imposto é um imposto indirecto, geral sobre o consumo e de matriz comunitária. Para que possamos ter noção de quando o imposto é devido e se torna exigível por parte do Estado, é essencial ter em conta as normas sobre o facto gerador e a exigibilidade do imposto. A Lei 15/2009, que entrou em vigor a 1 de Janeiro de 2009, consagra um novo regime de exigibilidade do IVA para a...

  5. A Second-order Impact Model for Forest Fire Regimes

    OpenAIRE

    Maggi, S. (Stefania); Rinaldi, S

    2006-01-01

    We present a very simple "impact" model for the description of forest fires and show that it can mimic the known characteristics of wild fire regimes in savannas, boreal forests, and Mediterranean forests. Moreover, the distribution of burned biomasses in model generated fires resemble those of burned areas in numerous large forests around the world. The model has also the merits of being the first second-order model for forest fires and the first example of the use of impact models in the st...

  6. A second-order impact model for forest fire regimes.

    Science.gov (United States)

    Maggi, Stefano; Rinaldi, Sergio

    2006-09-01

    We present a very simple "impact" model for the description of forest fires and show that it can mimic the known characteristics of wild fire regimes in savannas, boreal forests, and Mediterranean forests. Moreover, the distribution of burned biomasses in model generated fires resemble those of burned areas in numerous large forests around the world. The model has also the merits of being the first second-order model for forest fires and the first example of the use of impact models in the study of ecosystems. PMID:16723147

  7. Dynamics of aircraft exhaust plumes in the jet-regime

    Directory of Open Access Journals (Sweden)

    P. Fabian

    Full Text Available A computational model describing the two-dimensional, turbulent mixing of a single jet of exhaust gas from aircraft engines with the ambient atmosphere is presented. The underlying assumptions and governing equations are examined and supplemented by a discussion of analytical solutions. As an application, the jet dynamics of a B747-400 aircraft engine in cruise and its dependence on key parameters is investigated in detail. The computer code for this dynamical model is computationally fast and can easily be coupled to complex chemical and microphysical models in order to perform comprehensive studies of atmospheric effects from aircraft exhaust emissions in the jet regime.

  8. Climate-driven regime shift of a temperate marine ecosystem.

    Science.gov (United States)

    Wernberg, Thomas; Bennett, Scott; Babcock, Russell C; de Bettignies, Thibaut; Cure, Katherine; Depczynski, Martial; Dufois, Francois; Fromont, Jane; Fulton, Christopher J; Hovey, Renae K; Harvey, Euan S; Holmes, Thomas H; Kendrick, Gary A; Radford, Ben; Santana-Garcon, Julia; Saunders, Benjamin J; Smale, Dan A; Thomsen, Mads S; Tuckett, Chenae A; Tuya, Fernando; Vanderklift, Mathew A; Wilson, Shaun

    2016-07-01

    Ecosystem reconfigurations arising from climate-driven changes in species distributions are expected to have profound ecological, social, and economic implications. Here we reveal a rapid climate-driven regime shift of Australian temperate reef communities, which lost their defining kelp forests and became dominated by persistent seaweed turfs. After decades of ocean warming, extreme marine heat waves forced a 100-kilometer range contraction of extensive kelp forests and saw temperate species replaced by seaweeds, invertebrates, corals, and fishes characteristic of subtropical and tropical waters. This community-wide tropicalization fundamentally altered key ecological processes, suppressing the recovery of kelp forests. PMID:27387951

  9. Magnetic geometry and particle source drive of supersonic divertor regimes

    International Nuclear Information System (INIS)

    We present a comprehensive picture of the mechanisms driving the transition from subsonic to supersonic flows in tokamak plasmas. We demonstrate that supersonic parallel flows into the divertor volume are ubiquitous at low density and governed by the divertor magnetic geometry. As the density is increased, subsonic divertor plasmas are recovered. On detachment, we show the change in particle source can also drive the transition to a supersonic regime. The comprehensive theoretical analysis is completed by simulations in ITER geometry. Such results are essential in assessing the divertor performance and when interpreting measurements and experimental evidence. (technical note)

  10. A schematic model for QCD II finite temperature regime

    CERN Document Server

    Jesgarz, S; Hess, P O; Civitarese, O; Reboiro, M

    2003-01-01

    A schematic model for QCD, developed in a previous paper, is applied to calculate meson properties in the high temperature (up to 0.5 GeV) regime. It is a Lipkin model for quark-antiquark pairs coupled to gluon pairs of spin zero. The partition function is constructed with the obtained meson spectrum and several thermodynamical observables are calculated, like: the energy density, heat capacity, as well as relative production rates of mesons and absolute production rates for pions and kaons. The model predictions show a qualitative agreement with data. Based on these results we advocate the use of the model as a toy model for QCD.

  11. Chaotic scattering in the regime of weakly overlapping resonances.

    Science.gov (United States)

    Dietz, B; Friedrich, T; Harney, H L; Miski-Oglu, M; Richter, A; Schäfer, F; Weidenmüller, H A

    2008-11-01

    We measure the transmission and reflection amplitudes of microwaves in a resonator coupled to two antennas at room temperature in the regime of weakly overlapping resonances and in a frequency range of 3-16GHz . Below 10.1GHz the resonator simulates a chaotic quantum system. The distribution of the elements of the scattering matrix S is not Gaussian. The Fourier coefficients of S are used for a best fit of the autocorrelation function of S to a theoretical expression based on random-matrix theory. We find very good agreement below but not above 10.1GHz .

  12. Quantum regime of resonant-tunnelling diode oscillations

    International Nuclear Information System (INIS)

    Resonant-tunneling diode (RTD) is one of the first quantum devices. In contrast to devices settled on quantum dots and quantum threads, which works only at low temperatures, RTD can works in a wide range of temperatures from liquid-helium temperature till 100C. Also, RTD has one more feature, which makes this device attractive for use in integrated circuits-high operating frequency and, as a consequence, fast response. In this work we investigated free-running lasing of RTD in quantum regime.

  13. Ion holes in the hydrodynamic regime in ultracold neutral plasmas

    Energy Technology Data Exchange (ETDEWEB)

    McQuillen, P.; Castro, J.; Strickler, T.; Bradshaw, S. J.; Killian, T. C. [Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States)

    2013-04-15

    We describe the creation of localized density perturbations, or ion holes, in an ultracold neutral plasma in the hydrodynamic regime, and show that the holes propagate at the local ion acoustic wave speed. We also observe the process of hole splitting, which results from the formation of a density depletion initially at rest in the plasma. One-dimensional, two-fluid hydrodynamic simulations describe the results well. Measurements of the ion velocity distribution also show the effects of the ion hole and confirm the hydrodynamic conditions in the plasma.

  14. Giant and tunable electric field enhancement in the terahertz regime.

    Science.gov (United States)

    Lu, Xiaoyuan; Wan, Rengang; Wang, Guoxi; Zhang, Tongyi; Zhang, Wenfu

    2014-11-01

    A novel array of slits design combining the nano-slit grating and dielectric-metal is proposed to obtain giant and tunable electric field enhancement in the terahertz regime. The maximum amplitude of electric field is more than 6000 times larger than that of the incident electric field. It is found that the enhancement depends primarily on the stripe and nano-slits width of grating, as well as the thickness of spacer layer. This property is particularly beneficial for the realization of ultra-sensitive nanoparticles detection and nonlinear optics in the terahertz range, such as the second harmonic generation (SHG).

  15. The Numerical Modeling of Transient Regimes of Diesel Generator Sets

    Directory of Open Access Journals (Sweden)

    Cristian Roman

    2010-07-01

    Full Text Available This paper deals with the numerical modeling of a diesel generator set used as amain energy source in isolated areas and as a back-up energy source in the case ofrenewable energy systems. The numerical models are developed using a Matlab/Simulinksoftware package and they prove to be a powerful tool for the computer aided design ofcomplex hybrid power systems. Several operation regimes of the equipment are studied.The numerical study is completed with experimental measurements on a Kipor type dieselelectricgenerator set.

  16. Intergenerational Justice Perceptions and the Role of Welfare Regimes

    DEFF Research Database (Denmark)

    Sabbagh, Clara; Vanhuysse, Pieter

    2010-01-01

    , different welfare regimes structure young people's perceptions of the justness of public resources transfers from young to elderly age-groups and (2) the perceived relative contributions and rewards of various age-groups. Thus we inquire about both the perceived support in principle and about the perceived......-statist' ideological frame (the endorsement of egalitarian redistribution and broad state responsibility for welfare provision and the attribution of social inequality to external causes), and negatively with a 'market-based' frame (individualism, a work ethic, and internal attribution). Regarding actual outcomes...

  17. Geometric Constraints from Subregion Duality Beyond the Classical Regime

    CERN Document Server

    Akers, Chris; Leichenauer, Stefan; Levine, Adam

    2016-01-01

    Subregion duality in AdS/CFT implies certain constraints on the geometry: entanglement wedges must contain causal wedges, and nested boundary regions must have nested entanglement wedges. We elucidate the logical connections between these statements and the Quantum Focussing Conjecture, Quantum Null Energy Condition, Boundary Causality Condition, and Averaged Null Energy Condition. Our analysis does not rely on the classical limit of bulk physics, but instead works to all orders in \\(G\\hbar \\sim 1/N\\). This constitutes a nontrivial check on the consistency of subregion duality, entanglement wedge reconstruction, and holographic entanglement entropy beyond the classical regime.

  18. Why fiscal regimes matter for fiscal sustainability analysis: an application to France

    OpenAIRE

    Aldama, Pierre; Creel, Jérôme

    2016-01-01

    This paper introduces a Regime-Switching Model-Based Sustainability test allowing for periodic (or local) violations of Bohn (1998, QJE)’s sustainability condition. We assume a Markov-switching fiscal policy rule whose parameters stochastically switch between sustainable and unsustainable regimes. We demonstrate that long-run fiscal sustainability not only depends on regime-specific feedback coefficients of the fiscal policy rule but also on the average durations of fiscal regimes. Evidence o...

  19. Testing the Existence of Ricardian or Non-Ricardian Regimes for CIS Countries

    Directory of Open Access Journals (Sweden)

    Gulcin Guresci PEHLIVAN

    2016-03-01

    Full Text Available It is important to determine the dominant fiscal regime in a country group for policy prevision. This paper examines whether the Ricardian fiscal regime or non-Ricardian fiscal regime is dominant in the Common Wealth of Independent States (CIS. We attempted to show that CIS’ behavior after the debt stock increase. Using panel data method, this paper finds that Ricardian regime dominates in Kyrgyz Republic, Russian Federation, Tajikistan, Uzbekistan, Moldova and Turkmenistan’s fiscal policies.

  20. Trends in the International Regime of Liability and Compensation for Oil Pollution Damage

    Institute of Scientific and Technical Information of China (English)

    张秋荣

    2001-01-01

    Since the entry into force of the International Convention on liability and compensation for oil spill damage, there have been many discussions on the improvement of this regime. Based on the existing tworegimes, the writer tried to analysis the advantages of the new regimes and foresee the trends of the international regime of liability and compensation for oil pollution damage.

  1. Poloidal potential in the low-collisionality regime in a nonaxisymmetric torus

    International Nuclear Information System (INIS)

    The poloidal potential is calculated numerically in the low-collisionality regime for nonaxisymmetric tori such as stellarators and bumpy tori. It is found that even fairly deep into the superbanana regime, the poloidal potential retains the simple azimuthal dependence of the plateau regime. 12 refs., 8 figs

  2. Numerical study of flame structure in the mild combustion regime

    Directory of Open Access Journals (Sweden)

    Mardani Amir

    2015-01-01

    Full Text Available In this paper, turbulent non-premixed CH4+H2 jet flame issuing into a hot and diluted co-flow air is studied numerically. This flame is under condition of the moderate or intense low-oxygen dilution (MILD combustion regime and related to published experimental data. The modelling is carried out using the EDC model to describe turbulence-chemistry interaction. The DRM-22 reduced mechanism and the GRI2.11 full mechanism are used to represent the chemical reactions of H2/methane jet flame. The flame structure for various O2 levels and jet Reynolds numbers are investigated. The results show that the flame entrainment increases by a decrease in O2 concentration at air side or jet Reynolds number. Local extinction is seen in the upstream and close to the fuel injection nozzle at the shear layer. It leads to the higher flame entertainment in MILD regime. The turbulence kinetic energy decay at centre line of jet decreases by an increase in O2 concentration at hot Co-flow. Also, increase in jet Reynolds or O2 level increases the mixing rate and rate of reactions.

  3. Approaches to defining reference regimes for river restoration planning

    Science.gov (United States)

    Beechie, T. J.

    2014-12-01

    Reference conditions or reference regimes can be defined using three general approaches, historical analysis, contemporary reference sites, and theoretical or empirical models. For large features (e.g., floodplain channels and ponds) historical data and maps are generally reliable. For smaller features (e.g., pools and riffles in small tributaries), field data from contemporary reference sites are a reasonable surrogate for historical data. Models are generally used for features that have no historical information or present day reference sites (e.g., beaver pond habitat). Each of these approaches contributes to a watershed-wide understanding of current biophysical conditions relative to potential conditions, which helps create not only a guiding vision for restoration, but also helps quantify and locate the largest or most important restoration opportunities. Common uses of geomorphic and biological reference conditions include identifying key areas for habitat protection or restoration, and informing the choice of restoration targets. Examples of use of each of these three approaches to define reference regimes in western USA illustrate how historical information and current research highlight key restoration opportunities, focus restoration effort in areas that can produce the largest ecological benefit, and contribute to estimating restoration potential and assessing likelihood of achieving restoration goals.

  4. Enforcing the climate regime: Game theory and the Marrakesh Accords

    International Nuclear Information System (INIS)

    The article reviews basic insights about compliance and ''hard'' enforcement that can be derived from various non-cooperative equilibrium concepts and evaluates the Marrakesh Accords in light of these insights. Five different notions of equilibrium are considered - the Nash equilibrium, the sub game perfect equilibrium, the re negotiation proof equilibrium, the coalition proof equilibrium and the perfect Bayesian equilibrium. These various types of equilibrium have number of implications for effective enforcement: 1. Consequences of non-compliance should be more than proportionate. 2. To be credible punishment needs to take place in the Pareto frontier, rather than by reversion to some suboptimal state. 3. An effective enforcement system must be able to curb collective as well as individual incentives to cheat. 4. A fully transparent enforcement regime could in fact turn out to be detrimental for compliance levels. It is concluded that constructing an effective system for ''hard'' enforcement of the Kyoto Protocol is a formidable task that has only partially been accomplished by the Marrakesh Accords. A possible explanation is that the design of a compliance system for the climate regime involved a careful balancing of the desire to minimise non-compliance against other important considerations. (Author)

  5. Two-fluid MHD Regime of Drift Wave Instability

    Science.gov (United States)

    Yang, Shang-Chuan; Zhu, Ping; Xie, Jin-Lin; Liu, Wan-Dong

    2015-11-01

    Drift wave instabilities contribute to the formation of edge turbulence and zonal flows, and thus are believed to play essential roles in the anomalous transport processes in tokamaks. Whereas drift waves are generally assumed to be local and electrostatic, experiments have often found regimes where the spatial scales and the magnetic components of drift waves approach those of magnetohydrodynamic (MHD) processes. In this work we study such a drift wave regime in a cylindrical magnetized plasma using a full two-fluid MHD model implemented in the NIMROD code. The linear dependency of growth rates on resistivity and the dispersion relation found in the NIMROD calculations qualitatively agree with theoretical analysis. As the azimuthal mode number increases, the drift modes become highly localized radially; however, unlike the conventional local approximation, the radial profile of the drift mode tends to shift toward the edge away from the center of the density gradient slope, suggesting the inhomogeneity of two-fluid effects. Supported by National Natural Science Foundation of China Grant 11275200 and National Magnetic Confinement Fusion Science Program of China Grant 2014GB124002.

  6. Differentially Rotating White Dwarfs I: Regimes of Internal Rotation

    CERN Document Server

    Ghosh, Pranab

    2016-01-01

    Most viable models of Type Ia supernovae (SN~Ia) require the thermonuclear explosion of a carbon/oxygen white dwarf that has evolved in a binary system. Rotation could be an important aspect of any model for SN~Ia, whether single or double degenerate, with the white dwarf mass at, below, or above the Chandrasekhar limit. {\\sl Differential rotation} is specifically invoked in attempts to account for the apparent excess mass in the super--Chandrasekhar events. Some earlier work has suggested that only uniform rotation is consistent with the expected mechanisms of angular momentum transport in white dwarfs, while others have found pronounced differential rotation. We show that if the baroclinic instability is active in degenerate matter and the effects of magnetic fields are neglected, both nearly-uniform and strongly-differential rotation are possible. We classify rotation regimes in terms of the Richardson number, Ri. At small values of Ri $\\leq$ 0.1, we find both the low-viscosity Zahn regime with a non-monot...

  7. Enforcing the climate regime: Game theory and the Marrakesh Accords

    Energy Technology Data Exchange (ETDEWEB)

    Hovi, Jon

    2002-07-01

    The article reviews basic insights about compliance and ''hard'' enforcement that can be derived from various non-cooperative equilibrium concepts and evaluates the Marrakesh Accords in light of these insights. Five different notions of equilibrium are considered - the Nash equilibrium, the sub game perfect equilibrium, the re negotiation proof equilibrium, the coalition proof equilibrium and the perfect Bayesian equilibrium. These various types of equilibrium have number of implications for effective enforcement: 1. Consequences of non-compliance should be more than proportionate. 2. To be credible punishment needs to take place in the Pareto frontier, rather than by reversion to some suboptimal state. 3. An effective enforcement system must be able to curb collective as well as individual incentives to cheat. 4. A fully transparent enforcement regime could in fact turn out to be detrimental for compliance levels. It is concluded that constructing an effective system for ''hard'' enforcement of the Kyoto Protocol is a formidable task that has only partially been accomplished by the Marrakesh Accords. A possible explanation is that the design of a compliance system for the climate regime involved a careful balancing of the desire to minimise non-compliance against other important considerations. (Author)

  8. Making pore choices: repeated regime shifts in stomatal ratio.

    Science.gov (United States)

    Muir, Christopher D

    2015-08-22

    Ecologically important traits do not evolve without limits. Instead, evolution is constrained by the set of available and viable phenotypes. In particular, natural selection may only favour a narrow range of adaptive optima constrained within selective regimes. Here, I integrate data with theory to test whether selection explains phenotypic constraint. A global database of 599 plant species from 94 families shows that stomatal ratio, a trait affecting photosynthesis and defence against pathogens, is highly constrained. Most plants have their stomata on the lower leaf surface (hypostomy), but species with half their stomata on each surface (amphistomy) form a distinct mode in the trait distribution. A model based on a trade-off between maximizing photosynthesis and a fitness cost of upper stomata predicts a limited number of adaptive solutions, leading to a multimodal trait distribution. Phylogenetic comparisons show that amphistomy is the most common among fast-growing species, supporting the view that CO2 diffusion is under strong selection. These results indicate that selective optima stay within a relatively stable set of selective regimes over macroevolutionary time. PMID:26269502

  9. Political Regime and Human Capital: A Cross-Country Analysis.

    Science.gov (United States)

    Klomp, Jeroen; de Haan, Jakob

    2013-03-01

    We examine the relationship between different dimensions of the political regime in place and human capital using a two-step structural equation model. In the first step, we employ factor analysis on 16 human capital indicators to construct two new human capital measures (basic and advanced human capital). In the second step, we estimate the impact of our political variables on human capital, using a cross-sectional structural model for some 100 countries. We conclude that democracy is positively related to basic human capital, while regime instability has a negative link with basic human capital. Governance has a positive relationship with advanced human capital, while government instability has a negative link with advanced human capital. Finally, we also find an indirect positive effect of governance and democracy on both types of human capital through their effect on income. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11205-011-9983-6) contains supplementary material, which is available to authorized users.

  10. Impurity accumulation in plasma regimes with high energy confinement

    Science.gov (United States)

    Ran, L. B.; Roberts, D. E.; Yang, H. R.; Dodel, G.; Gentle, K.; Von Goeler, S.; Holzhauer, E.; Hübner, K.; Keilhacker, M.; Korotkov, A.; Luce, T. C.; Miura, Y.; Tsois, N.; Würz, H.; Fussmann, G.; Hofmann, J.; Janeschitz, G.; Krieger, K.; Müller, E. R.; Nolte, R.; Röhr, H.; Steuer, K. H.; Becker, G.; Bomba, B.; Bruhns, H.; Büchl, K.; Carlson, A.; Eberhagen, A.; Fahrbach, H.-U.; Gehre, O.; Gernhardt, J.; Giannone, L.; Von Gierke, G.; Glock, E.; Gruber, O.; Haas, G.; Herrmann, H.; Kaesdorf, S.; Karger, F.; Kaufmann, M.; Klüber, O.; Kornherr, M.; Lackner, K.; Lang, R.; Lee, P.; Lisitano, G.; Mast, F.; Mayer, H. M.; McCormick, K.; Meisel, D.; Mertens, V.; Murmann, H.; Neuhauser, J.; Niedermeyer, H.; Noterdaeme, J. M.; Poschenrieder, W.; Preis, R.; Rapp, H.; Rudyj, A.; Sandmann, W.; Schneider, F.; Schnider, U.; Siller, G.; Simmet, E.; Speth, E.; Söldner, F.; Stäbler, A.; Steinmetz, K.; Stroth, U.; Vollmer, O.; Zasche, D.

    1989-04-01

    Investigations of impurity accumulation phenomena in ASDEX are reviewed. There are four different operating regimes where pronounced accumulation is observed and these regimes are also characterized by improved energy confinement. In particular, medium-Z metallic ions are involved in accumulation processes whereas low-Z ions appear almost unaffected. The rapid accumulation observed in the case of metallic ions may be explained by neoclassical inward drifts if we assume that the anomalous diffusion is sufficiently suppressed, some indication of this being found from laser blow-off studies. The present results, however, can only be partly explained by neoclassical theory, according to which accumulation of low-Z impurities should also occur. The temporal behaviour of accumulation and the retarding effect of proton dilution for collision dominated transport are also discussed. Finally, we conclude that the full benefits of improved energy confinement can be achieved only if the impurity influxes are kept to a sufficiently low level. Expressed in terms of concentrations under low confinement conditions we have to postulate, for ASDEX, concentrations ≲ 10 -4 for metals and ≲ 2% for all light impurities.

  11. Hydroperiod regime controls the organization of plant species in wetlands.

    Science.gov (United States)

    Foti, Romano; del Jesus, Manuel; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio

    2012-11-27

    With urban, agricultural, and industrial needs growing throughout the past decades, wetland ecosystems have experienced profound changes. Most critically, the biodiversity of wetlands is intimately linked to its hydrologic dynamics, which in turn are being drastically altered by ongoing climate changes. Hydroperiod regimes, e.g., percentage of time a site is inundated, exert critical control in the creation of niches for different plant species in wetlands. However, the spatial signatures of the organization of plant species in wetlands and how the different drivers interact to yield such signatures are unknown. Focusing on Everglades National Park (ENP) in Florida, we show here that cluster sizes of each species follow a power law probability distribution and that such clusters have well-defined fractal characteristics. Moreover, we individuate and model those signatures via the interplay between global forcings arising from the hydroperiod regime and local controls exerted by neighboring vegetation. With power law clustering often associated with systems near critical transitions, our findings are highly relevant for the management of wetland ecosystems. In addition, our results show that changes in climate and land management have a quantifiable predictable impact on the type of vegetation and its spatial organization in wetlands.

  12. Modeling viscosity and diffusion of plasma mixtures across coupling regimes

    Science.gov (United States)

    Arnault, Philippe

    2014-10-01

    Viscosity and diffusion of plasma for pure elements and multicomponent mixtures are modeled from the high-temperature low-density weakly coupled regime to the low-temperature high-density strongly coupled regime. Thanks to an atom in jellium modeling, the effect of electron screening on the ion-ion interaction is incorporated through a self-consistent definition of the ionization. This defines an effective One Component Plasma, or an effective Binary Ionic Mixture, that is representative of the strength of the interaction. For the viscosity and the interdiffusion of mixtures, approximate kinetic expressions are supplemented by mixing laws applied to the excess viscosity and self-diffusion of pure elements. The comparisons with classical and quantum molecular dynamics results reveal deviations in the range 20--40% on average with almost no predictions further than a factor of 2 over many decades of variation. Applications in the inertial confinement fusion context could help in predicting the growth of hydrodynamic instabilities.

  13. Finite element modelling of the Harwell regional groundwater flow regime

    International Nuclear Information System (INIS)

    In assessing the feasibility of a geological disposal site for low and intermediate level radioactive wastes, a detailed knowledge of the hydrogeological system is essential because dissolution and transport of any disposed waste would be controlled ultimately by the rate and direction of groundwater movement. This report describes a case study of the use of a finite element computer program to model the groundwater flow of the Harwell region. The aim of the work was to produce a numerical model which calculated results that compared closely to the observed features of the groundwater flow regime. The model results will then provide information about the groundwater head distribution and flow pattern between the points of observation, and these results may be used in determining the nature of any future applied field studies. A secondary aim of the modelling process was to assess the usefulness of the computer program for modelling groundwater flow in a layered sedimentary environment. The groundwater flow regime of the Harwell region has been modelled using the two dimensional NAMMU finite element computer program which calculates the groundwater head distribution and resultant groundwater flow pattern. (author)

  14. Numerical simulation of dip-coating in the evaporative regime.

    Science.gov (United States)

    Dey, Mohar; Doumenc, Frédéric; Guerrier, Béatrice

    2016-02-01

    A hydrodynamic model is used for numerical simulations of a polymer solution in a dip-coating-like experiment. We focus on the regime of small capillary numbers where the liquid flow is driven by evaporation, in contrast to the well-known Landau-Levich regime dominated by viscous forces. Lubrication approximation is used to describe the flow in the liquid phase. Evaporation in stagnant air is considered (diffusion-limited evaporation), which results in a coupling between liquid and gas phases. Self-patterning due to the solutal Marangoni effect is observed for some ranges of the control parameters. We first investigate the effect of evaporation rate on the deposit morphology. Then the role of the spatial variations in the evaporative flux on the wavelength and mean thickness of the dried deposit is ascertained, by comparing the 2D and 1D diffusion models for the gas phase. Finally, for the very low substrate velocities, we discuss the relative importance of diffusive and advective components of the polymer flux, and consequences on the choice of the boundary conditions. PMID:26920522

  15. Regimes de financiamento, risco crescente do endividamento e fragilidade financeira

    Directory of Open Access Journals (Sweden)

    Gilberto Tadeu Lima

    2005-06-01

    Full Text Available Elabora-se um modelo macroeconômico de curto prazo na tradição pós-keynesiana, no qual a oferta de crédito é endógena e o grau de endividamento das firmas é explicitamente modelado. Relacionam-se as condições de vigência dos regimes minskyanos de financiamento - hedge, especulativo ou Ponzi - não somente ao grau de endividamento e à taxa de juros, mas, inclusive, aos parâmetros da função investimento desejado da firmas e à propensão a poupar dos capitalistas produtivos e financeiros.It is developed a short-run macromodel in the post-keynesian tradition, in which credit supply is endogenous and firms' debt position is explicitly modeled. The conditions under which each one of the minskyan financing regimes will prevail are related not only to the degree of indebtedness and the level of interest rate, but also to the parameters of firms' desired investment function and the saving propensity of productive and financial capitalists.

  16. The New Legal Regime on Minority Shareholder Protection in Albania

    Directory of Open Access Journals (Sweden)

    Jonida Rustemaj

    2012-10-01

    Full Text Available This article aims at introducing the main changes brought by the new Albanian Company Law on minority shareholders’ protection. Due to the harmonization of our legislation with the acqui, new pieces of laws were introduced in commercial law. In 2008 the new law “On entrepreneurs and commercial companies” was enacted. The latter introduced new practices and concepts, some of them not familiar to the Albanian legal system. I was motivated to write a paper on minority shareholders protection in order to emphasize the new regime and instruments of protection granted by the new laws. A matter which concerns investors and especially foreign ones is the protection of minority shareholders. This paper discusses the instruments of protection of minority shareholders bringing the novelties of the newly introduced laws because of the unclear regime under the repealed law using the analytical and comparative method. Few rights which were known by the former Albanian company law were usually compromised, but under the law in force, minorities are much more protected.Does the new law strengthen the position of such category of shareholders? What are the rights of minority shareholders conferred by the law? These and other questions will be addressed herein.

  17. Low-Energy QCD in the Delta Regime

    CERN Document Server

    Matzelle, Matthew E

    2015-01-01

    We investigate properties of low-energy QCD in a finite spatial volume, but with arbitrary temperature. In the limit of small temperature and small cube size compared to the pion Compton wavelength, Leutwyler has shown that the effective theory describing low-energy QCD reduces to that of quantum mechanics on the coset manifold, which is the so-called delta regime of chiral perturbation theory. We solve this quantum mechanics analytically for the case of a $U(1)_L \\times U(1)_R$ subgroup of chiral symmetry, and numerically for the case of $SU(2)_L \\times SU(2)_R$. We utilize the quantum mechanical spectrum to compute the mass gap and chiral condensate, and investigate symmetry restoration in a finite spatial volume as a function of temperature. Because we obtain the spectrum for non-zero values of the quark mass, we are able to interpolate between the rigid rotor limit, which emerges at vanishing quark mass, and the harmonic approximation, which is referred to as the p-regime. We find that the applicability o...

  18. The present status of the CTBT verification regime

    International Nuclear Information System (INIS)

    The Comprehensive nuclear-Test-Ban Treaty (CTBT) was opened for signature on September 24, 1996. As of November 17, 2006 the numbers of Signatories and Ratifications are 177 and 137 respectively. The Preparatory Commission for the CTBT Organization, which consists of Signatures, has been preparing for the verification regime in order to monitor compliance with the Treaty. With 10 years passage the International Monitoring System is switching from establishing to operating phase and has functioned effectively to detect nuclear explosions. On the other hand many issues has arisen in long pending of not entering into force, which was not supposed in early time; for example restructuring of the organization for conforming operational body and its nature and status and technology refreshment. Also data globally acquired are being used for civil and scientific applications and attempts are made with increasing interaction between the Organization, Signatories and scientific community. This paper presents an overview of status of the verification regime, discuss future course and issues, and also expresses JAEA's programme related to the CTBT. (author)

  19. Oscillations in the bistable regime of neuronal networks

    Science.gov (United States)

    Roxin, Alex; Compte, Albert

    2016-07-01

    Bistability between attracting fixed points in neuronal networks has been hypothesized to underlie persistent activity observed in several cortical areas during working memory tasks. In network models this kind of bistability arises due to strong recurrent excitation, sufficient to generate a state of high activity created in a saddle-node (SN) bifurcation. On the other hand, canonical network models of excitatory and inhibitory neurons (E-I networks) robustly produce oscillatory states via a Hopf (H) bifurcation due to the E-I loop. This mechanism for generating oscillations has been invoked to explain the emergence of brain rhythms in the β to γ bands. Although both bistability and oscillatory activity have been intensively studied in network models, there has not been much focus on the coincidence of the two. Here we show that when oscillations emerge in E-I networks in the bistable regime, their phenomenology can be explained to a large extent by considering coincident SN and H bifurcations, known as a codimension two Takens-Bogdanov bifurcation. In particular, we find that such oscillations are not composed of a stable limit cycle, but rather are due to noise-driven oscillatory fluctuations. Furthermore, oscillations in the bistable regime can, in principle, have arbitrarily low frequency.

  20. Testing for regime-switching CAPM on Zagreb Stock Exchange

    Directory of Open Access Journals (Sweden)

    Tihana Škrinjarić

    2014-12-01

    Full Text Available The standard Capital Asset Pricing Model assumes that a linear relationship exists between the risk (beta and the expected excess return of a stock. However, empirical findings have shown over the years that this relationship varies over time. Stock markets undergo phases of greater and smaller volatility in which beta varies accordingly (undergoes different regimes. Given that the Croatian capital market is still insufficiently investigated, the aim of this paper is to explore the possibility of a non-linear relationship between the stock risk and return. Linear and Markov-switching models (Hamilton 1989 are examined on the Zagreb Stock Exchange based on monthly data on 21 stocks, ranging from January 2005 to December 2013. In that way, investors can use the results based on the best model when making decisions about buying stocks. Since this is one of the first papers on regime-switching on the Croatian capital market, it will hopefully contribute to the existing literature on investing.

  1. Consequences of more extreme precipitation regimes for terrestrial ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, Alan [Colorado State University, Fort Collins; Beier, Claus [Riso National Laboratory, Roskilde, Denmark; Briske, David [Texas A& M University; Classen, Aimee T [ORNL; Luo, Yiqi [University of Oklahoma; Reichstein, Markus [Max Planck Institute for Biogeochemistry; Smith, Melinda D [Yale University; Smith, Stanley D [University of Nevada, Las Vegas; Bell, Jesse E [University of Oklahoma; Fay, Philip [ORNL; Heisler, Jana A [Colorado State University, Fort Collins; Leavitt, Steven W [unknown; Sherry, Rebecca [University of Oklahoma; Smith, Ben [unknown; Weng, Ensheng [University of Oklahoma, Norman; Norby, Richard J [ORNL

    2008-09-01

    Amplification of the hydrological cycle, as a consequence of global warming, is forecast to be manifest not only by alterations in total annual precipitation, but also through more extreme precipitation regimes characterized by larger rainfall events and more severe intervening drought periods. Based on past studies and theory, we present a conceptual framework for predicting the consequences of this projected change in intra-annual rainfall patterns for terrestrial ecosystems arrayed along a broad gradient in water availability. More extreme rainfall regimes are predicted to increase the occurrence of periodic soil water stress in mesic ecosystems due to prolonged dry periods between rainfall events. In contrast, xeric ecosystems may exhibit the opposite response because a shift to a greater proportion of rainfall delivered in large precipitation events will result in reduced proportional evaporative losses per storm event and greater soil water storage, alleviating soil water stress for longer periods of time. Hydric ecosystems may experience reduced periods of anoxia if intervals between rainfall events increase. This contingent effect of the overall soil water balance on ecosystem responses will likely cascade through all hierarchical levels of ecological processes and interact in ways currently unknown with related global change drivers such as elevated atmospheric temperatures and CO2 concentrations. Thus, multi-factor comparative experiments and systems modeling approaches are needed to more fully understand and forecast the potential ecological consequences of this underappreciated aspect of climate change.

  2. Transport in Porous Fins From Laminar to Turbulent Regime

    Science.gov (United States)

    Coletti, Filippo; Muramatsu, Kenshiro; Furciniti, Brian; Elkins, Chris; Eaton, John

    2012-11-01

    Lotus type porous metal has elongated pores of random size and spatial distribution but a common orientation. Sets of so-called lotus fins are obtained by slicing the metal into thin layers and stacking them in the flow path, forcing the fluid to pass through the pores. Lotus fins represent a promising alternative to metal foam heat exchangers, because they offer higher thermal conductivity and lower pressure drop. We have experimentally analyzed the fluid flow and heat transfer in lotus fins to determine their transport properties in a range of flow regimes. The investigated Reynolds numbers based on the pore diameter and inner velocity ranged from 100 to 4000. Three-dimensional mean velocity fields were obtained by magnetic resonance velocimetry performed on magnified replicas of the fins, allowing determination of the mechanical dispersion imposed by the random structure of the fins. Thermal measurements on non-conductive fins provided the global diffusivity coefficient, which accounts for molecular, mechanical and (at high Reynolds number) turbulent diffusion. The latter contribution was isolated and its relevance assessed as a function of the flow regime.

  3. Fano-Andreev effect in Quantum Dots in Kondo regime

    Science.gov (United States)

    Orellana, Pedro; Calle, Ana Maria; Pacheco, Monica; Apel, Victor

    In the present work, we investigate the transport through a T-shaped double quantum dot system coupled to two normal leads and to a superconducting lead. We study the role of the superconducting lead in the quantum interferometric features of the double quantum dot and by means of a slave boson mean field approximation at low temperature regime. We inquire into the influence of intradot interactions in the electronic properties of the system as well. Our results show that Fano resonances due to Andreev bound states are exhibited in the transmission from normal to normal lead as a consequence of quantum interference and proximity effect. This Fano effect produced by Andreev bound states in a side quantum dot was called Fano-Andreev effect, which remains valid even if the electron-electron interaction are taken into account, that is, the Fano-Andreev effect is robust against e-e interactions even in Kondo regime. We acknowledge the financial support from FONDECYT program Grants No. 3140053 and 11400571.

  4. A new fast reconnection model in a collisionless regime

    CERN Document Server

    Tsiklauri, David

    2008-01-01

    Based on the first principles (by balancing the advection with the electron pressure tensor in the generalised Ohm's law, and using the conservation of mass) a simple model of magnetic reconnection in a collisionless regime is formulated. In addition to its importance from the fundamental point of view, the collisionless reconnection model offers a much faster reconnection rate ($M_{c'less}={(d_i/2)}^{1/2}$) than Sweet-Parker's classical one ($M_{sp}=S^{-1/2}$). The width of the diffusion region (current sheet) in the collisionless regime is found to be $\\delta_{c'less}={(d_i/2)}^{1/2}L$, which is much larger than the Sweet-Parker width ($\\delta_{sp}=S^{-1/2}L$) for the space plasma conditions. Amongst other issues, this alleviates e.g. the problem of interpretation of solar flares by means of reconnection, as for the typical solar coronal parameters the obtained collisionless reconnection time can be $< 10$ minutes, as opposed to Sweet-Parker's equivalent value of $<$ year. The new theoretical reconnec...

  5. Nutrient regimes control phytoplankton ecophysiology in the South Atlantic

    Directory of Open Access Journals (Sweden)

    T. J. Browning

    2013-07-01

    Full Text Available Fast Repetition Rate fluorometry (FRRf measurements of phytoplankton photophysiology from an across-basin South Atlantic cruise (as part of the GEOTRACES programme characterized two dominant ecophysiological regimes which were interpreted on the basis of nutrient limitation. South of the South Subtropical Convergence (SSTC in the northern sub-Antarctic sector of the Antarctic Circumpolar Current (ACC in the Eastern Atlantic Basin, waters are characterized by elevated chlorophyll concentrations, a dominance by larger phytoplankton cells, and low apparent photochemical efficiency (Fv / Fm. Shipboard 24 h iron (Fe addition incubation experiments confirmed that Fe stress was primarily responsible for the low Fv / Fm, with Fe addition to these waters, either within the artificial bottle additions or naturally occurring downstream enrichment from Gough Island, significantly increasing Fv / Fm values. Satellite images suggest a broader region of enhanced chlorophyll concentrations around the SSTC in the Western Atlantic relative to the Eastern Atlantic: hypothesized to be a result of higher iron supply from the South American continent. To the north of the SSTC at the southern boundary of the South Atlantic Gyre, phytoplankton are characterized by high values of Fv / Fm which, coupled with the low macronutrient concentrations and increased presence of picocyanobacteria, are interpreted as conditions of Fe replete, balanced macronutrient-limited growth. Spatial correlation was found between Fv / Fm and Fe:nitrate ratios, supporting the suggestion that the relative supply ratios of these two nutrients can control patterns of limitation and consequently the ecophysiology of phytoplankton in subtropical gyre and ACC regimes.

  6. Oscillations in the bistable regime of neuronal networks.

    Science.gov (United States)

    Roxin, Alex; Compte, Albert

    2016-07-01

    Bistability between attracting fixed points in neuronal networks has been hypothesized to underlie persistent activity observed in several cortical areas during working memory tasks. In network models this kind of bistability arises due to strong recurrent excitation, sufficient to generate a state of high activity created in a saddle-node (SN) bifurcation. On the other hand, canonical network models of excitatory and inhibitory neurons (E-I networks) robustly produce oscillatory states via a Hopf (H) bifurcation due to the E-I loop. This mechanism for generating oscillations has been invoked to explain the emergence of brain rhythms in the β to γ bands. Although both bistability and oscillatory activity have been intensively studied in network models, there has not been much focus on the coincidence of the two. Here we show that when oscillations emerge in E-I networks in the bistable regime, their phenomenology can be explained to a large extent by considering coincident SN and H bifurcations, known as a codimension two Takens-Bogdanov bifurcation. In particular, we find that such oscillations are not composed of a stable limit cycle, but rather are due to noise-driven oscillatory fluctuations. Furthermore, oscillations in the bistable regime can, in principle, have arbitrarily low frequency.

  7. Institutional effectiveness in international regimes. An analysis of the effectiveness of the nuclear non-proliferation regime coping with the political malignity in the case of Iran

    International Nuclear Information System (INIS)

    Among the international security regimes, the Nuclear Non-Proliferation Regime has a prominent ranking due to the destructive power of the nuclear weapons over regional and global peace and stability. The NPT Regime has come across with two major challenges in the recent decade: North Korea and Iran. Contrary to North Korea, Iran is determined to stay as a state party to the Nuclear Non-Proliferation Treaty. The Regime still did not confirm the character and extent of Iranian nuclear program. The question of this study is ''why the processes of the NPT Regime cannot specify the nature and scope of Irans nuclear program?'' The three main the processes of the regime, which are the International Atomic Energy Agency (IAEA), the UN Security Council (UNSC) and the multilateral negotiations, are examined to determine the weaknesses of the regime. This study argues that the regime is modulated to cope with operational challenges and it remains relatively incompetent when a political challenge arises.

  8. The Kyoto protocol: assessment and perspectives. Towards a new regime up to the climate stake

    International Nuclear Information System (INIS)

    This report proposes an analysis within the context of transition of the climate regime from the 'before-2012' regime to the 'post-2020' regime. It first gives an overview of international stakes and context (lack of ambition for climate policy, perspective of an international agreement from 2020). Then, the authors recall the history and achievements of the Kyoto protocol which is the basis of the present climate policy regime. They propose an assessment of actions performed by countries during the first period of the protocol, and focus on the present climate regime elements which are to be safeguarded. They analyse the weaknesses of the present regime, and propose possible improvements for the future post-2020 climate regime

  9. World-Ecology and Ireland: The Neoliberal Ecological Regime

    Directory of Open Access Journals (Sweden)

    Sharae Deckard

    2016-03-01

    Full Text Available Since the collapse of the Celtic Tiger, the socio-economic particularity of neoliberal capitalism in its Irish manifestation has increasingly been critiqued, but little attention has been paid to neoliberalism as ecology within Ireland. This article conducts an exploratory survey of the characteristics of the Irish neoliberal ecological regime during and after the Celtic Tiger, identifying the opening of new commodity frontiers (such as fracking, water, agro-biotechnology, and biopharma constituted in the neoliberal drive to appropriate and financialize nature. I argue for the usefulness of applying not only the tools of world-systems analysis, but also Jason W. Moore’s world-ecological paradigm, to analysis of Ireland as a semi-periphery. What is crucial to a macro-ecological understanding of Ireland’s role in the neoliberal regime of the world-ecology is the inextricability of its financial role as a tax haven and secrecy jurisdiction zone from its environmental function as a semi-peripheral pollution and water haven. We can adapt Jason W. Moore’s slogan that “Wall Street…becomes a way of organizing all of nature, characterized by the financialization of any income-generating activity” (Moore 2011b: 39 to say that to say that the “IFSC is a way of organizing nature,” with pernicious consequences for water, energy, and food systems in Ireland. Financial service centers and pharmaceutical factories, plantations and cattle ranches, tax havens and pollution havens, empires and common markets are all forms of environment-making that constellate human relations and extra-human processes into new ecological regimes. More expansive, dialectical understandings of “ecology” as comprising the whole of socio-ecological relations within the capitalist world-ecology—from farming to pharma to financialization—are crucial to forming configurations of knowledge able not only to take account of Ireland’s role in the environmental

  10. Historical thermal regimes define limits to coral acclimatization.

    Science.gov (United States)

    Howells, Emily J; Berkelmans, Ray; van Oppen, Madeleine J H; Willis, Bette L; Bay, Line K

    2013-05-01

    Knowledge of the degree to which corals undergo physiological acclimatization or genetic adaptation in response to changes in their thermal environment is crucial to the success of coral reef conservation strategies. The potential of corals to acclimatize to temperatures exceeding historical thermal regimes was investigated by reciprocal transplantation of Acropora millepora colonies between the warm central and cool southern regions of the Great Barrier Reef (GBR) for a duration of 14 months. Colony fragments retained at native sites remained healthy, whereas transplanted fragments, although healthy over initial months when temperatures remained within native thermal regimes, subsequently bleached and suffered mortality during seasonal temperature extremes. Corals hosting Symbiodinium D transplanted to the southern GBR bleached in winter and the majority suffered whole (40%; n=20 colonies) or partial (50%) mortality at temperatures 1.1 degrees C below their 15-year native minimum. In contrast, corals hosting Symbiodinium C2 transplanted to the central GBR bleached in summer and suffered whole (50%; n=10 colonies) or partial (42%) mortality at temperatures 2.5 degrees C above their 15-year native maximum. During summer bleaching, the dominant Symbiodinium type changed from C2 to D within corals transplanted to the central GBR. Corals transplanted to the cooler, southern GBR grew 74-80% slower than corals at their native site, and only 50% of surviving colonies reproduced, at least partially because of cold water bleaching of transplants. Despite the absence of any visual signs of stress, corals transplanted to the warmer, central GBR grew 52-59% more slowly than corals at their native site before the summer bleaching (i.e., from autumn to spring). Allocation of energy to initial acclimatization or reproduction may explain this pattern, as the majority (65%) of transplants reproduced one month earlier than portions of the same colonies retained at the southern

  11. Babinet's principle in the Fresnel regime studied using ultrasound

    CERN Document Server

    Hitachi, Akira

    2009-01-01

    Babinet's principle in the Fresnel regime has been confirmed directly by observing ultrasound diffracted by a circular disk and an aperture of the same size. The amplitude and the phase of diffracted ultrasonic waves have been measured and a graphical treatment of the results is performed. It is also found that the wave without the diffracting objects is indeed 90 deg in phase behind the wave from the center of the zone system. This paradox has previously been regarded as a defect of Fresnel's theory. The 90 deg phase difference appears also in Fresnel-Kirchhoff diffraction, Rayleigh-Sommerfeld diffraction and even in the edge-diffracted approach by Young. The apparatus used is intended as a table-top instrument for the student laboratory in general science and engineering classes.

  12. The Legal Regime of the Right to Administrate Public Property

    Directory of Open Access Journals (Sweden)

    Vasilica Negruţ

    2014-05-01

    Full Text Available The traditional institutions for administrative law, public property and the public domain have been the subject of numerous specialized papers from the interwar period. After 1990, the two institutions were discussed in light of the new legislative rules. Within this article we propose to analyze, based on the distinction between the notions of public property and public domain, the legal regime of the right to administrate assets of public property. Is this a real right appropriate for public property or just a simple competence of administration and management of public domain assets? Analyzing and comparing the opinions, the arguments expressed by specialists and the current legislation in this area, we conclude that the administrative right is a real right suitable for public property.

  13. Gamma-ray Explosion in Multiple Compton Scattering Regime

    CERN Document Server

    Gong, Z; Shou, Y R; Qiao, B; Bulanov, S V; Esirkepov, T Zh; Bulanov, S S; Chen, C E; He, X T; Yan, X Q

    2016-01-01

    Gamma-ray explosion from near critical density (NCD) target irradiated by four symmetrical imploding laser pulses is numerically investigated. With peak intensities about $10^{23}$ W/cm$^2$, the laser pulses boost electron energy through direct laser acceleration, while pushing them inward with the ponderomotive force. After backscattering with counter-propagating laser, the accelerated electron will be trapped in the optical lattice or the electromagnetic standing waves (SW) created by the coherent overlapping of the laser pulses, and meanwhile emit gamma-ray photon in Multiple Compton Scattering regime, where electron acts as a medium to transfer energy from laser to gamma-ray. The energy conversion rate from laser pulses to gamma-ray can be as high as around 50\\%. It may become one of the most efficient gamma-ray sources in laboratory.

  14. Fluid mobility over corrugated surfaces in the Stokes regime

    Science.gov (United States)

    Shelley, S. R.; Smith, J. D.; Hibbins, A. P.; Sambles, J. R.; Horsley, S. A. R.

    2016-08-01

    An exact solution is found for laminar fluid flow along the grooves of a family of surfaces whose shape is given by the Lambert W-function. This simple solution allows for the slip length in the direction parallel to the grooves to be calculated exactly. With this analytical model, we establish the regime of validity for a previously untested perturbation theory intended for calculating the surface mobility tensor of arbitrary periodic surfaces, finding that it compares well to the exact expression for nearly all choices of parameters of the conformal map. To test this perturbation theory further, the mobility tensor is evaluated for a simple sinusoidal surface for flow both parallel and perpendicular to the grooves, finding that the perturbation theory is less accurate in the latter of these two cases.

  15. Nanowire-based thermoelectric ratchet in the hopping regime

    Science.gov (United States)

    Bosisio, Riccardo; Fleury, Geneviève; Pichard, Jean-Louis; Gorini, Cosimo

    2016-04-01

    We study a thermoelectric ratchet consisting of an array of disordered nanowires arranged in parallel on top of an insulating substrate and contacted asymmetrically to two electrodes. Transport is investigated in the Mott hopping regime, when localized electrons can propagate through the nanowires via thermally assisted hops. When the electronic temperature in the nanowires is different from the phononic one in the substrate, we show that a finite electrical current is generated even in the absence of driving forces between the electrodes. We discuss the device performance both as an energy harvester, when an excess heat from the substrate is converted into useful power, and as a refrigerator, when an external power is supplied to cool down the substrate.

  16. Assessment of Global Variability in UTBB MOSFETs in Subthreshold Regime

    Directory of Open Access Journals (Sweden)

    Sergej Makovejev

    2014-07-01

    Full Text Available The global variability of ultra-thin body and buried oxide (UTBB MOSFETs in subthreshold and off regimes of operation is analyzed. The variability of the off-state drain current, subthreshold slope, drain-induced barrier lowering (DIBL, gate leakage current, threshold voltage and their correlations are considered. Two threshold voltage extraction techniques were used. It is shown that the transconductance over drain current (gm/Id method is preferable for variability studies. It is demonstrated that the subthreshold drain current variability in short channel devices cannot be described by threshold voltage variability. It is suggested to include the effective body factor incorporating short channel effects in order to properly model the subthreshold drain current variability.

  17. First principles electron transport simulations in the Kondo regime

    Science.gov (United States)

    Rungger, Ivan; Radonjic, Milos; Appelt, Wilhelm; Chioncel, Liviu; Droghetti, Andrea

    When magnetic atoms, molecules or thin films are brought into contact with metals the electron-electron interaction leads to the appearance of the correlated Kondo state at low temperatures. In this talk we will present results for the electronic structure and conductance in the Kondo regime of recent STM and break junction experiments for stable radical molecules, which correspond to spin half molecular magnets. We will outline the methodological approach to evaluate the conductance of such systems from first principles, as implemented in the Smeagol electron transport code. The method combines the density functional theory (DFT) with Anderson impurity solvers within the continuum time quantum Monte Carlo (CTQMC) and numerical renormalization group (NRG) approaches.

  18. Weak interference in the high-signal regime.

    Science.gov (United States)

    Torres, Juan P; Puentes, Graciana; Hermosa, Nathaniel; Salazar-Serrano, Luis Jose

    2012-08-13

    Weak amplification is a signal enhancement technique which is used to measure tiny changes that otherwise cannot be determined because of technical limitations. It is based on: a) the existence of a weak interaction which couples a property of a system (the system) with a separate degree of freedom (the pointer), and b) the measurement of an anomalously large mean value of the pointer state (weak mean value), after appropriate pre-and post-selection of the state of the system. Unfortunately, the weak amplification process is generally accompanied by severe losses of the detected signal, which limits its applicability. However, we will show here that since weak amplification is essentially the result of an interference phenomena, it should be possible to use the degree of interference (weak interference) to get relevant information about the physical system under study in a more general scenario, where the signal is not severely depleted (high-signal regime). PMID:23038526

  19. Tokamak resistive magnetohydrodynamic ballooning instability in the negative shear regime

    Institute of Scientific and Technical Information of China (English)

    Shi Bing-Ren; Lin Jian-Long; Li Ji-Quan

    2007-01-01

    Improved confinement of tokamak plasma with central negative shear is checked against the resistive ballooning mode. In the negative shear regime, the plasma is always unstable for purely growing resistive ballooning mode. For a simplest tokamak equilibrium model, the s-α model, characteristics of this kind of instability are fully clarified by numerically solving the high n resistive magnetohydrodynamic ballooning eigen-equation. Dependences of the growth rate on the resistivity, the absolute shear value, the pressure gradient are scanned in detail. It is found that the growth rate is a monotonically increasing function of a while it is not sensitive to the changes of the shear s, the initial phase θ0 and the resistivity parameter εR.

  20. Three regimes of extrasolar planets inferred from host star metallicities

    CERN Document Server

    Buchhave, Lars A; Latham, David W; Sasselov, Dimitar; Cochran, William D; Endl, Michael; Isaacson, Howard; Juncher, Diana; Marcy, Geoffrey W

    2014-01-01

    Approximately half of the extrasolar planets (exoplanets) with radii less than four Earth radii are in orbits with short periods. Despite their sheer abundance, the compositions of such planets are largely unknown. The available evidence suggests that they range in composition from small, high-density rocky planets to low-density planets consisting of rocky cores surrounded by thick hydrogen and helium gas envelopes. Understanding the transition from the gaseous planets to Earth-like rocky worlds is important to estimate the number of potentially habitable planets in our Galaxy and provide constraints on planet formation theories. Here we report the abundances of heavy elements (that is, the metallicities) of more than 400 stars hosting 600 exoplanet candidates, and find that the exoplanets can be categorized into three populations defined by statistically distinct (~ 4.5{\\sigma}) metallicity regions. We interpret these regions as reflecting the formation regimes of terrestrial-like planets (radii less than 1...

  1. Transnational NGOs between Popular Uprising and Authoritarian Regime

    DEFF Research Database (Denmark)

    Farah, Abdulkadir Osman

    2013-01-01

    of disempowered youth, intense media-tech application and sustained international pressure as crucial to ousting authoritarian regimes in North Africa. Delineating the role of TNGOs complements such findings. TNGO activities and responses to the Egyptian uprising in 2011 and to the ensuing coup in 2013 reveal...... movements, organizations and communities engaged in de-territorialized socio‐cultural, political and economic activities. This paper focuses on the role of transnational NGOs (TNGOs) in recent developments in Egypt. The current scholarly debate on the so‐called “Arab spring” considers the mobilization...... positions of these organizations and might eventually encourage the return to authoritarianism. After introductory remarks on the background of the uprising, the paper proceeds to theoretical discussion of transnational engagement followed by recent historical and current empirical developments...

  2. Admittance measurements in the quantum Hall effect regime

    Energy Technology Data Exchange (ETDEWEB)

    Hernández, C., E-mail: carlos.hernandezr@unimilitar.edu.co [Departamento de Física, Universidad Militar Nueva Granada, Carrera 11 # 101-80, Bogotá D.C. (Colombia); Laboratorio de Magnetismo, Departamento de Física, Universidad de los Andes, A.A. 4976, Bogotá D.C. (Colombia); Consejo, C.; Chaubet, C. [Laboratoire Charles Coulomb L2C, Université Montpellier II, Pl. E. Bataillon, 34095 Montpellier Cedex 5 (France)

    2014-11-15

    In this work we present an admittance study of a two-dimensional electron gas (2DEG) in the quantum Hall effect (QHE) regime. We have studied several Hall bars in different contacts configurations in the frequency range 100 Hz–1 MHz. Our interpretation is based on the Landauer–Büttiker theory and takes into account both the capacitance and the topology of the coaxial cables which are connected to the sample holder. We show that we always observe losses through the capacitive impedance of the coaxial cables, except in the two contacts configuration in which the cable capacitance does not influence the admittance measurement of the sample. In this case, we measure the electrochemical capacitance of the 2DEG and show its dependence with the filling factor ν.

  3. Gravity-driven soap film dynamics in subcritical regimes

    Science.gov (United States)

    Auliel, M. I.; Castro, F.; Sosa, R.; Artana, G.

    2015-10-01

    We undertake the analysis of soap-film dynamics with the classical approach of asymptotic expansions. We focus our analysis in vertical soap film tunnels operating in subcritical regimes with elastic Mach numbers Me=O(10-1) . Considering the associated set of nondimensional numbers that characterize this flow, we show that the flow behaves as a two-dimensional (2D) divergence free flow with variable mass density. When the soap film dynamics agrees with that of a 2D and almost constant mass density flow, the regions where the second invariant of the velocity gradient is non-null correspond to regions where the rate of change of film thickness is non-negligible.

  4. Chiral effective field theory beyond the power-counting regime

    CERN Document Server

    Hall, Jonathan M M; Young, Ross D

    2011-01-01

    Novel techniques are presented, which identify the chiral power-counting regime (PCR), and realize the existence of an intrinsic energy scale embedded in lattice QCD results that extend outside the PCR. The nucleon mass is considered as a benchmark for illustrating this new approach. Using finite-range regularization, an optimal regularization scale can be extracted from lattice simulation results by analyzing the renormalization of the low energy coefficients. The optimal scale allows a description of lattice simulation results that extend beyond the PCR by quantifying and thus handling any scheme-dependence. Preliminary results for the nucleon magnetic moment are also examined, and a consistent optimal regularization scale is obtained. This indicates the existence of an intrinsic scale corresponding to the finite size of the source of the pion cloud.

  5. Power Counting Regime of Chiral Effective Field Theory and Beyond

    CERN Document Server

    Hall, J M M; Leinweber, D B

    2010-01-01

    Chiral effective field theory complements numerical simulations of quantum chromodynamics (QCD) on a space-time lattice. It provides a model-independent formalism for connecting lattice simulation results at finite volume and a variety of quark masses to the physical world. The asymptotic nature of the chiral expansion places the focus on the first few terms of the expansion. Thus, knowledge of the power-counting regime (PCR) of chiral effective field theory, where higher-order terms of the expansion may be regarded as negligible, is as important as knowledge of the expansion itself. Through the consideration of a variety of renormalization schemes and associated parameters, techniques to identify the PCR where results are independent of the renormalization scheme are established. The nucleon mass is considered as a benchmark for illustrating this general approach. Because the PCR is small, the numerical simulation results are also examined to search for the possible presence of an intrinsic scale which may b...

  6. Chiral extrapolation beyond the power-counting regime

    CERN Document Server

    Hall, J M M; Leinweber, D B; Liu, K F; Mathur, N; Young, R D; Zhang, J B

    2011-01-01

    Chiral effective field theory can provide valuable insight into the chiral physics of hadrons when used in conjunction with non-perturbative schemes such as lattice QCD. In this discourse, the attention is focused on extrapolating the mass of the rho meson to the physical pion mass in quenched QCD (QQCD). With the absence of a known experimental value, this serves to demonstrate the ability of the extrapolation scheme to make predictions without prior bias. By using extended effective field theory developed previously, an extrapolation is performed using quenched lattice QCD data that extends outside the chiral power-counting regime (PCR). The method involves an analysis of the renormalization flow curves of the low energy coefficients in a finite-range regularized effective field theory. The analysis identifies an optimal regulator, which is embedded in the lattice QCD data themselves. This optimal regulator is the regulator value at which the renormalization of the low energy coefficients is approximately i...

  7. Endemic time-spaces of Finland: Aquatic regimes

    Directory of Open Access Journals (Sweden)

    Tero Mustonen

    2014-08-01

    Full Text Available This article explores the endemic time-spaces of Finnish aquatic regimes. More precisely, it examines the socio-ecological relationships between Finns and lakes, rivers, and marshes-mires. First, the 'engine' of endemic time-space research, land use, and occupancy documentation, is explored in the Finnish context. Then two catchment areas, Kokemäenjoki in Western Finland and Vuoksi in Eastern Finland, provide cases which illustrate both past endemic time-spaces and surviving aspects of cultural readings of lakes and rivers. The ongoing winter seining in Lake Puruvesi in North Karelia emerges as an unbroken practice, with deep roots, that maintains the endemic time-spaces of a traditional Finnish relationship with a lake. As industrial uses of catchment areas, zoning, and environmental permitting exclude endemic readings inherent on the land and waterscapes, solutions are explored through mapping, along with its limitations, as a form bridging the gap between local realities and resource extraction.

  8. Transition from diffusive to localized regimes in surface corrugated waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Martin, A.; Saenz, J. J. [Universidad Autonoma de Madrid, Madrid (Spain); Nieto-Vesperinas, M. [Instituto de Ciencias de Materiales de Madrid, Madrid (Spain)

    2001-03-01

    Exact calculations of transmission and reflection coefficients in surface randomly corrugated waveguides are presented. The elastic scattering of diffuse light classical waves from a rough surface induces a diffusive transport along the waveguide axis. As the length of the corrugated part of the waveguide increases, a transition from the diffusive to the localized regime is observed. This involves an analogy with electron conduction in nano wires, and hence, a concept analogous to that of resistance can be introduced. An oscillatory behavior of different transport properties (elastic mean free path, localization length, enhanced backscattering), versus the wavelength is predicted. An analysis of the transmission coefficients (transmitted speckle) shows that as the length of the corrugated part of the waveguide increases there is a strong preference to forward coupling through the lowest mode. This marks a clear anisotropy in the forward propagation which is absent in the case of volume disorder. The statistics of reflection coefficients is analyzed, first using random matrix theory (Rm) to analytically deduce the probability densities in the localization regime, afterwards exact numerical calculations of the coupling to backward modes in surface corrugated waveguides will be put forward for comparison. We show that the reflected speckle distribution are independent of the transport regime, at variance with the regime transition found in the transmission case. Despite the strong anisotropy, the analysis of the probability distributions of both transmitted and reflected waves confirms the distributions predicted by Random Matrix Theory for volume disorder. [Spanish] Presentamos calculos exactos de los coeficientes de transmision y reflexion en guias de onda con desorden de superficie. La dispersion elastica de luz difusa o de otras ondas clasicas por una superficie rugosa induce un transporte difusivo a lo largo del eje de la guia. A medida que la longitud de la zona

  9. Principles Governing the Sustainability of Nuclear Security Regimes

    International Nuclear Information System (INIS)

    In order for nuclear security regimes, including nuclear security systems, to remain effective, they must be sustained over the long-term by States and by individual sites and installations. The objective of this paper is to define sustainability and provide a methodology for States, competent authorities, and operators on the content of sustainability programmes for nuclear security regimes. The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA) Global Threat Reduction Initiative (GTRI) and the Office of International Material Protection and Cooperation (IMPC) have developed a methodology promoting the sustainability of improvements to nuclear security systems for prevention, detection and interdiction of the illicit movement of nuclear and other radioactive materials. These recommendations will help ensure that the capabilities established or strengthened through State-sponsored programs and/or donor State assistance remain effective and are supported and sustained over the long term by the host countries and by individual sites or installations. Physical protection and material control and accounting upgrades at facilities and radiation detection capacity building at borders and interior locations are critical elements of a national nuclear security regime. The efficacy of these prevention, detection and response measures is wholly dependent on sustaining their functionality. The sustainability of nuclear security facility upgrades and border security measures is ultimately the responsibility of the host country and each individual site or installation. This paper will provide the principles, guidance, performance measures, and best practices for establishing, assessing, and maintaining this functionality at national, regional and site levels. The methodology proposed in the paper addresses the varied infrastructures encountered among States. The premise is the establishment of a sustainability program which will ensure a nuclear

  10. Corporate hedging under a resource rent tax regime

    Energy Technology Data Exchange (ETDEWEB)

    Frestad, Dennis [Department of Economics and Business Administration, University of Agder, Serviceboks 422, 4604 Kristiansand (Norway)

    2010-03-15

    In addition to the ordinary corporate income tax, special purpose taxes are sometimes levied to extract abnormal profits arising from the use of natural resources. Such dual tax regimes exist in Norway for oil and hydropower, where the corresponding special purpose tax bases are unaffected by any derivatives payments. Dual tax firms with hedging programs therefore face the risk of potentially large discrepancies between the tax bases for corporate income tax and special purpose tax. I investigate how this tax base asymmetry influences the extent of hedging of value-maximizing firms facing hedgeable as well as unhedgeable risk. Dual tax firms facing deadweight costs in low-profit events generally demand less hedging than ordinary firms, but otherwise respond similarly to characteristics of the underlying risk exposures. The special purpose tax does not influence firms' hedge portfolios in the absence of deadweight cost. (author)

  11. Nuclear quantum state engineering in ion channeling regime

    Directory of Open Access Journals (Sweden)

    Berec Vesna

    2015-01-01

    Full Text Available A key challenge in quantum state engineering is to identify coherent quantum mechanical systems that can be precisely manipulated and scaled, but at the same time to allow decoupling from unwanted interactions. Such systems, once realized, would represent an efficient tool for characterization of quantum behavior reflected in the properties of matter with prerequisites for meeting dissipation constraints imposed in the nuclear physics as well in the quantum information theory. Using the pure29Si nanocrystal system we present a novel high resolution method for initialization of single electron polarized spin interaction and control of nuclear spin qubits. The presented study fuses field of particle channeling in MeV energy regime with quantum state engineering utilized via entanglement as an essential quantum property. Its aim is to bring focus on new theoretical proposals testing the quantum mechanical models for systems producible at particle accelerator facilities.

  12. Two competing species in super-diffusive dynamical regimes

    Science.gov (United States)

    La Cognata, A.; Valenti, D.; Spagnolo, B.; Dubkov, A. A.

    2010-09-01

    The dynamics of two competing species within the framework of the generalized Lotka-Volterra equations, in the presence of multiplicative α-stable Lévy noise sources and a random time dependent interaction parameter, is studied. The species dynamics is characterized by two different dynamical regimes, exclusion of one species and coexistence of both, depending on the values of the interaction parameter, which obeys a Langevin equation with a periodically fluctuating bistable potential and an additive α-stable Lévy noise. The stochastic resonance phenomenon is analyzed for noise sources asymmetrically distributed. Finally, the effects of statistical dependence between multiplicative noise and additive noise on the dynamics of the two species are studied.

  13. The organization of global negotiations: constructing the climate change regime

    Energy Technology Data Exchange (ETDEWEB)

    Depledge, Joanna

    2005-02-15

    The basic assumption of this book is that the organization of a negotiation process matters. The global negotiations on climate change involve over 180 countries and innumerable observers and other participants, addressing enormously complex and economically vital issues with conflicting agendas. For the UN to create an effective and well-supported international regime has required enormous and very skilful organization: factors such as the role of the Chair, the choice of negotiating arenas, the rules for the conduct of business and the approach of negotiating texts are usually taken for granted, and rarely attract attention until something goes wrong. This book explores how the negotiations were organized to produce the Kyoto Protocol to the Climate Change Convention and the subsequent Bonn Agreements and Marrakesh Accords. The author draws out the lessons and implications for other intricate and far-reaching negotiations, not all of which have succeeded so far, such as the WTO trade negotiations at Seattle and Cancun. (Author)

  14. Comparison of different climate regimes: the impact of broadening participation

    International Nuclear Information System (INIS)

    So-far, most climate mitigation studies look at climate policy strategies in a so-called first-best world, i.e. using the least expensive emission reduction options in all world regions and sectors. To explore the impact of limited participation of countries, we have run a set of scenarios that explore the impact of introducing a carbon tax in OECD, the BRIC countries (Brazil Russia, India and China) and the rest of the world. The results show that carbon taxes can effectively reduce greenhouse gas emissions. However, if low greenhouse gas concentration levels are to be achieved, early participation (in some form) of large developing countries is important to increase reduction potential. It should be noted that global carbon taxes (without additional assumptions) lead to relatively high costs in low-income regions. Cap-and-trade regimes have more flexibility to create a comparable distribution of costs amongst countries.

  15. Detector noise statistics in the non-linear regime

    Science.gov (United States)

    Shopbell, P. L.; Bland-Hawthorn, J.

    1992-01-01

    The statistical behavior of an idealized linear detector in the presence of threshold and saturation levels is examined. It is assumed that the noise is governed by the statistical fluctuations in the number of photons emitted by the source during an exposure. Since physical detectors cannot have infinite dynamic range, our model illustrates that all devices have non-linear regimes, particularly at high count rates. The primary effect is a decrease in the statistical variance about the mean signal due to a portion of the expected noise distribution being removed via clipping. Higher order statistical moments are also examined, in particular, skewness and kurtosis. In principle, the expected distortion in the detector noise characteristics can be calibrated using flatfield observations with count rates matched to the observations. For this purpose, some basic statistical methods that utilize Fourier analysis techniques are described.

  16. Smooth horizonless geometries deep inside the black-hole regime

    CERN Document Server

    Bena, Iosif; Martinec, Emil J; Russo, Rodolfo; Shigemori, Masaki; Turton, David; Warner, Nicholas P

    2016-01-01

    We construct the first family of horizonless supergravity solutions that have the same mass, charges and angular momenta as general supersymmetric rotating D1-D5-P black holes in five dimensions. This family includes solutions with arbitrarily small angular momenta, deep within the regime of quantum numbers and couplings for which a large classical black hole exists. These geometries are well-approximated by the black-hole solution, and in particular exhibit the same near-horizon throat. Deep in this throat, the black-hole singularity is resolved into a smooth cap. We also identify the holographically-dual states in the N=(4,4) D1-D5 orbifold CFT. Our solutions are among the states counted by the CFT elliptic genus, and provide examples of smooth microstate geometries within the ensemble of supersymmetric black-hole microstates.

  17. Intensity interferometry in the x-ray regime

    International Nuclear Information System (INIS)

    Intensity interferometry in the x-ray regime was developed at the 27-m undulator beamline of SPring-8 for characterizing x-ray coherence properties. Ultrahigh-resolution monochromator with ΔE=120 μeV at E=14.4 keV was developed for obtaining large interference signal. Transverse coherence profiles were measured by the coincidence method with changing the vertical slit width after the monochromator. The result agreed with the relationship expected from the Van Cittert-Zernike's theorem. The source size deduced from the result was compared to that given by the visible light interferometer. X-ray pulse width was determined by changing the bandwidth of monochromator. Application of the method to the fourth generation synchrotron sources was discussed. (author)

  18. Stimulated Brillouin scattering revisited: Strong coupling regime and Rabi splitting

    CERN Document Server

    Huy, Kien Phan; Tchahame, Joel Cabrel; Sylvestre, Thibaut

    2015-01-01

    Stimulated Brillouin scattering in optical waveguides is a fundamental interaction between light and acoustic waves mediated by electrostriction and photoelasticity. In this paper, we revisit the usual theory of this inelastic scattering process to get a joint system in which the acoustic wave is strongly coupled to the interference pattern between the optical waves. We show in particular that, when the optoacoustic coupling rate is comparable to the phonon damping rate, the system enters in the strong coupling regime, giving rise to avoided crossing of the dispersion curve and Rabi-like splitting. We further find that optoacoustic Rabi splitting could in principle be observed using backward stimulated Brillouin scattering in sub-wavelength diameter tapered optical fibers with moderate peak pump power.

  19. Employing Acoustic Emission for Monitoring Oil Film Regimes

    Directory of Open Access Journals (Sweden)

    David Mba

    2013-07-01

    Full Text Available The major purpose of a gear lubricant is to provide adequate oil film thickness to reduce and prevent gear tooth surface failures. Real time monitoring for gear failures is important in order to predict and prevent unexpected failures which would have a negative impact on the efficiency, performance and safety of the gearbox. This paper presents experimental results on the influence of specific oil film thickness on Acoustic Emission (AE activity for operational helical gears. Variation in film thickness during operations was achieved by spraying liquid nitrogen onto the rotating gear wheel. The experimental results demonstrated a clear relationship between the root mean square (r.m.s value of the AE signal and the specific film thickness. The findings demonstrate the potential of Acoustic Emission technology to quantify lubrication regimes on operational gears.

  20. Flow regimes and heat transfer in vertical narrow annuli

    Energy Technology Data Exchange (ETDEWEB)

    Ulke, A.; Goldberg, I.

    1993-11-01

    In shell side boiling heat exchangers narrow crevices that are formed between the tubes and the tube support structure provide areas for local thermal-hydraulic conditions which differ significantly from bulk fluid conditions. Understanding of the processes of boiling and dryout in flow restricted crevices can help in designing of tube support geometries to minimize the likelihood of tube support plate and tube corrosion observed in commercial power plant steam generators. This paper describes a one dimensional thermal-hydraulic model of a vertical crevice between a tube and a support plate with cylindrical holes. The annulus formed by the support plate hole and an eccentrically located tube has been represented by vertical strips. The formation, growth and collapse of a steam bubble in each strip has been determined. Based on the bubble history, and flow regimes characterized by ``isolated`` bubbles, ``coalesced`` bubbles and liquid deficient regions have been defined.

  1. Flow regimes and heat transfer in vertical narrow annuli

    International Nuclear Information System (INIS)

    In shell side boiling heat exchangers narrow crevices that are formed between the tubes and the tube support structure provide areas for local thermal-hydraulic conditions which differ significantly from bulk fluid conditions. Understanding of the processes of boiling and dryout in flow restricted crevices can help in designing of tube support geometries to minimize the likelihood of tube support plate and tube corrosion observed in commercial power plant steam generators. This paper describes a one dimensional thermal-hydraulic model of a vertical crevice between a tube and a support plate with cylindrical holes. The annulus formed by the support plate hole and an eccentrically located tube has been represented by vertical strips. The formation, growth and collapse of a steam bubble in each strip has been determined. Based on the bubble history, and flow regimes characterized by ''isolated'' bubbles, ''coalesced'' bubbles and liquid deficient regions have been defined

  2. Semiclassical regime of Regge calculus and spin foams

    International Nuclear Information System (INIS)

    Recent attempts to recover the graviton propagator from spin foam models involve the use of a boundary quantum state peaked on a classical geometry. The question arises whether beyond the case of a single simplex this suffices for peaking the interior geometry in a semiclassical configuration. In this paper we explore this issue in the context of quantum Regge calculus with a general triangulation. Via a stationary phase approximation, we show that the boundary state succeeds in peaking the interior in the appropriate configuration, and that boundary correlations can be computed order by order in an asymptotic expansion. Further, we show that if we replace at each simplex the exponential of the Regge action by its cosine-as expected from the semiclassical limit of spin foam models-then the contribution from the sign-reversed terms is suppressed in the semiclassical regime and the results match those of conventional Regge calculus

  3. Quantifying flooding regime in floodplain forests to guide river restoration

    Directory of Open Access Journals (Sweden)

    Christian O. Marks

    2014-09-01

    Full Text Available Abstract Determining the flooding regime needed to support distinctive floodplain forests is essential for effective river conservation under the ubiquitous human alteration of river flows characteristic of the Anthropocene Era. At over 100 sites throughout the Connecticut River basin, the largest river system in New England, we characterized species composition, valley and channel morphology, and hydrologic regime to define conditions promoting distinct floodplain forest assemblages. Species assemblages were dominated by floodplain-associated trees on surfaces experiencing flood durations between 4.5 and 91 days/year, which were generally well below the stage of the two-year recurrence interval flood, a widely-used benchmark for floodplain restoration. These tree species rarely occurred on surfaces that flooded less than 1 day/year. By contrast abundance of most woody invasive species decreased with flooding. Such flood-prone surfaces were jointly determined by characteristics of the hydrograph (high discharges of long duration and topography (low gradient and reduced valley constraint, resulting in increased availability of floodplain habitat with increasing watershed area and/or decreasing stream gradient. Downstream mainstem reaches provided the most floodplain habitat, largely associated with low-energy features such as back swamps and point bars, and were dominated by silver maple (Acer saccharinum. However, we were able to identify a number of suitable sites in the upper part of the basin and in large tributaries, often associated with in-channel islands and bars and frequently dominated by sycamore (Platanus occidentalis and flood disturbance-dependent species. Our results imply that restoring flows by modifying dam operations to benefit floodplain forests on existing surfaces need not conflict with flood protection in some regional settings. These results underscore the need to understand how flow, geomorphology, and species traits

  4. Probing of polymer surfaces in the viscoelastic regime.

    Science.gov (United States)

    Chyasnavichyus, Marius; Young, Seth L; Tsukruk, Vladimir V

    2014-09-01

    In this Feature Article, we discussed the experimental and modeling methods and analyzed the limitations of the surface probing of nanomechanical properties of polymeric and biological materials in static and dynamic regimes with atomic force microscopy (AFM), which are widely utilized currently. To facilitate such measurements with minimized ambiguities, in this study we present a combined method to evaluate the viscoelastic properties of compliant polymeric materials. We collected force-distance data in the static regime for a benchmark polymer material (poly(n-butyl methacrylate)) with an easily accessible glass-transition temperature (about 25 °C) at different loading rates and different temperatures across the glassy state, glass-transition region, and rubbery state. For this analysis, we exploited a Johnson-modified Sneddon's approach in a combination with the standard linear solid model. Critical experimental steps suggested for robust probing are (i) the use of a tip with a well-characterized parabolic shape, (ii) probing in a liquid environment in order to reduce jump-in phenomenon, and (iii) minute indentations to ensure the absence of plastic deformation. Whereas the standard Sneddon's model generates quantitatively adequate elastic modulus values below and above the glass transition, this traditional approach can significantly underestimate actual modulus values in the vicinity of the glass-transition region (15 °C above or below Tg), with major deviations occurring at the loss tangent peak. The analysis of the experimental data with Sneddon's model for the elastic region (glassy and rubbery states) and Johnson's model for the viscoelastic region allowed for the restoration of the universal master curve and the evaluation of the storage modulus, loss modulus, loss tangent, relaxation times, and activation energies of the polymer surface across the glass-transition region and at relevant loading rates. PMID:24512573

  5. Global patterns of change in discharge regimes for 2100

    Directory of Open Access Journals (Sweden)

    F. C. Sperna Weiland

    2012-04-01

    Full Text Available This study makes a thorough global assessment of the effects of climate change on hydrological regimes and their accompanying uncertainties. Meteorological data from twelve GCMs (SRES scenarios A1B and control experiment 20C3M are used to drive the global hydrological model PCR-GLOBWB. This reveals in which regions of the world changes in hydrology can be detected that have a high likelihood and are consistent amongst the ensemble of GCMs. New compared to existing studies is: (1 the comparison of spatial patterns of regime changes and (2 the quantification of notable consistent changes calculated relative to the GCM specific natural variability. The resulting consistency maps indicate in which regions the likelihood of hydrological change is large.

    Projections of different GCMs diverge widely. This underscores the need of using a multi-model ensemble. Despite discrepancies amongst models, consistent results are revealed: by 2100 the GCMs project consistent decreases in discharge for southern Europe, southern Australia, parts of Africa and southwestern South-America. Discharge decreases strongly for most African rivers, the Murray and the Danube while discharge of monsoon influenced rivers slightly increases. In the Arctic regions river discharge increases and a phase-shift towards earlier peaks is observed. Results are comparable to previous global studies, with a few exceptions. Globally we calculated an ensemble mean discharge increase of more than ten percent. This increase contradicts previously estimated decreases, which is amongst others caused by the use of smaller GCM ensembles and different reference periods.

  6. Global patterns of change in discharge regimes for 2100

    Directory of Open Access Journals (Sweden)

    F. C. Sperna Weiland

    2011-12-01

    Full Text Available This study makes a thorough global assessment of the effects of climate change on hydrological regimes and their accompanying uncertainties. Meteorological data from twelve GCMs (SRES scenarios A1B, and control experiment 20C3M are used to drive the global hydrological model PCR-GLOBWB. We reveal in which regions of the world changes in hydrology can be detected that are significant and consistent amongst the ensemble of GCMs. New compared to existing studies is: (1 the comparison of spatial patterns of regime changes and (2 the quantification of consistent significant change calculatesd relative to both the natural variability and the inter-model spread. The resulting consistency maps indicate in which regions likelihood of hydrological change is large.

    Projections of different GCMs diverge widely. This underscores the need of using a multi-model ensemble. Despite discrepancies amongst models, consistent results are revealed: by 2100 the GCMs project consistent decreases in discharge for southern Europe, southern Australia, parts of Africa and southwestern South-America. Discharge decreases are large for most African rivers, the Murray and the Danube. While discharge of Monsoon influenced rivers slightly increases. In the Arctic regions river discharge increases and a phase-shift towards earlier peaks is observed. Results are comparable to previous global studies, with a few exceptions. Globally we calculated an ensemble mean discharge increase of more than ten percent. This increase contradicts previously estimated decreases, which is amongst others caused by the use of smaller GCM ensembles and different reference periods.

  7. Delay-Limited Capacity in the Low Power Regime

    KAUST Repository

    Rezki, Zouheir

    2016-02-11

    Outage performance of the M-block fading with additive white Gaussian noise (BF-AWGN) is investigated in the low-power regime. We consider delay-constrained constant-rate communications with perfect channel state information (CSI) at both the transmitter and the receiver (CSI-TR), under a shortterm power constraint (STPC) and a long-term power constraint (LTPC). Subject to STPC, we show that selection diversity that allocates all the power to the strongest block is asymptotically optimal. Then, we provide a simple characterization of the outage probability in the regime of interest. We quantify the reward due to CSI-TR over the constant-rate constant-power scheme and show that this reward increases with the delay constraint. For instance, for Rayleigh fading, we find that a power gain up to 4.3 dB is achievable. Subject to LTPC, we show that the above guidelines still holds and that the outage performance improves due to the flexibility of the LTPC over the STPC. More interestingly, we prove that LTPC allows zero-outage communication even at low SNR and characterize the delaylimited capacity at low SNR in a simple form. More precisely, we establish that the delay-limited capacity scales linearly with the power constraint, for a given M < 1. Our framework highlights the benefit of fading at low SNR as the delay-limited capacity may outperform the AWGN capacity. For instance, for Rayleigh fading and with M = 3, the delay-limited capacity is 16% higher than the capacity of an AWGN channel.

  8. Landscape-scale forest disturbance regimes in southern Peruvian Amazonia.

    Science.gov (United States)

    Boyd, Doreen S; Hill, Ross A; Hopkinson, Chris; Baker, Timothy R

    2013-10-01

    Landscape-scale gap-size frequency distributions in tropical forests are a poorly studied but key ecological variable. Currently, a scale gap currently exists between local-scale field-based studies and those employing regional-scale medium-resolution satellite data. Data at landscape scales but of fine resolution would, however, facilitate investigation into a range of ecological questions relating to gap dynamics. These include whether canopy disturbances captured in permanent sample plots (PSPs) are representative of those in their surrounding landscape, and whether disturbance regimes vary with forest type. Here, therefore, we employ airborne LiDAR data captured over 142.5 km2 of mature, swamp, and regenerating forests in southeast Peru to assess the landscape-scale disturbance at a sampling resolution of up to 2 m. We find that this landscape is characterized by large numbers of small gaps; large disturbance events are insignificant and infrequent. Of the total number of gaps that are 2 m2 or larger in area, just 0.45% were larger than 100 m2, with a power-law exponent (alpha) value of the gap-size frequency distribution of 2.22. However, differences in disturbance regimes are seen among different forest types, with a significant difference in the alpha value of the gap-size frequency distribution observed for the swamp/regenerating forests compared with the mature forests at higher elevations. Although a relatively small area of the total forest of this region was investigated here, this study presents an unprecedented assessment of this landscape with respect to its gap dynamics. This is particularly pertinent given the range of forest types present in the landscape and the differences observed. The coupling of detailed insights into forest properties and growth provided by PSPs with the broader statistics of disturbance events using remote sensing is recommended as a strong basis for scaling-up estimates of landscape and regional-scale carbon balance. PMID

  9. The New Legal Regime On Minority Shareholder Protection In Albania

    Directory of Open Access Journals (Sweden)

    Jonida Rustemaj

    2012-09-01

    Full Text Available This article aims at introducing the main changes brought by  the new Albanian Company Law on  minority shareholders’ protection. Due to the harmonization of our legislation with the acqui, new pieces of laws were introduced in commercial law. In 2008 the new law “On entrepreneurs and commercial companies” was enacted. The latter introduced new practices and concepts, some of them not  familiar  to  the Albanian  legal  system. I  was motivated  to   write  a  paper on   minority   shareholders protection  in  order to  emphasize  the new regime  and instruments of protection granted by the new laws. A matter which concerns investors and especially foreign ones is the protection of minority  shareholders. This paper discusses the instruments  of  protection  of  minority   shareholders bringing the novelties of the newly introduced laws because of  the unclear regime under the repealed law using the analytical and comparative method. Few rights which  were known by the former Albanian company law were usually compromised, but  under the law in  force, minorities are much more protected. Does the new law strengthen the position of such category of   shareholders?   What  are   the   rights   of   minority shareholders  conferred  by  the  law?  These  and other questions will be addressed herein.

  10. Implications of climate change on flow regime affecting Atlantic salmon

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The UKCIP02 climate change scenarios (2070–2100 suggest that the UK climate will become warmer (an overall increase of 2.5–3°C, with temperature increases being greater in the summer and autumn than in the spring and winter seasons. In terms of precipitation, winters are expected to become wetter and summers drier throughout the UK. The effect of changes in the future climate on flow regimes are investigated for the Atlantic salmon, Salmo salar, in a case study in an upland UK river. Using a hydraulic modelling approach, flows simulated across the catchment are assessed in terms of hydraulic characteristics (discharge per metre width, flow depths, flow velocities and Froude number. These, compared with suitable characteristics published in the literature for various life stages of Atlantic salmon, enable assessment of habitat suitability. Climate change factors have been applied to meteorological observations in the Eden catchment (north-west England and effects on the flow regime have been investigated using the SHETRAN hydrological modelling system. High flows are predicted to increase by up to 1.5%; yet, a greater impact is predicted from decreasing low flows (e.g. a Q95 at the outlet of the study catchment may decrease to a Q85 flow. Reliability, Resilience and Vulnerability (RRV analysis provides a statistical indication of the extent and effect of such changes on flows. Results show that future climate will decrease the percentage time the ideal minimum physical habitat requirements will be met. In the case of suitable flow depth for spawning activity at the outlet of the catchment, the percentage time may decrease from 100% under current conditions to 94% in the future. Such changes will have implications for the species under the Habitats Directive and for catchment ecological flow management strategies.

  11. Using Biofuel Tracers to Study Alternative Combustion Regimes

    Energy Technology Data Exchange (ETDEWEB)

    Mack, J H; Flowers, D L; Buchholz, B A; Dibble, R W

    2006-02-14

    Interest in the use of alternative fuels and combustion regimes is increasing as the price of petroleum climbs. The inherently higher efficiency of Diesel engines has led to increased adoption of Diesels in Europe, capturing approximately 40% of the new passenger car market. Unfortunately, lower CO{sub 2} emissions are countered with higher nitrogen oxides (NOx) and particulate matter (PM) emissions, and higher noise. Noise and PM have traditionally been the obstacles toward consumer acceptance of Diesel passenger cars in North America, while NOx (a key component in photochemical smog) has been more of an engineering challenge. Diesels are lean burning (combustion with excess oxygen) and reducing NOx to N2 in an oxygen rich environment is difficult. Adding oxygenated compounds to the fuel helps reduce PM emissions, but relying on fuel alone to reduce PM is unrealistic. Keeping peak combustion temperature below 1700 K prevents NOx formation. Altering the combustion regime to burn at temperatures below the NOx threshold and accept a wide variety of fuels seems like a promising alternative for future engines. Homogeneous Charge Compression Ignition (HCCI) is a possible solution. Fuel and air are well mixed prior to intake into a cylinder (homogeneous charge) and ignition occurs by compression of the fuel-air mixture by the piston. HCCI is rapid and relatively cool, producing little NOx and PM. Unfortunately, it is hard to control since HCCI is initiated by temperature and pressure instead of a spark or direct fuel injection. We investigate biofuel HCCI combustion, and use intrinsically labeled biofuels as tracers of HCCI combustion. Data from tracer experiments are used to validate combustion modeling.

  12. CFD characterization of flow regimes inside open cell foam substrates

    International Nuclear Information System (INIS)

    Highlights: • We investigated the pressure drop in open-cell foams. • The study is based on a combination of micro-CT, image-based modeling and CFD tools. • Detailed CFD simulations were applied for the investigation of turbulent flow regimes. • The effects of geometrical parameters are studied by means of RANS CFD simulations. • Results are analyzed in terms of non-dimensional parameters. - Abstract: In this work a combination of micro-CT, image-based modeling and CFD has been applied to investigate the pressure drop in open-cell foams. The analysis covers a range of flow regimes and is aimed at determining the effects of important morphological parameters on the pressure drop. The adoption of micro-CT technology along with detailed CFD modeling allows the investigation of phenomena occurring in real foam micro-structures. Moreover, by means of image processing tools, the geometry can be artificially modified in order to investigate the effects of mathematical transformation of the geometrical parameters of a real foam, one parameter at a time, e.g. varying pore size without affecting the porosity. Non-dimensional coefficients have been defined for the analysis of the results, with the purpose of describing the pressure drop as a function of the Reynolds number. The proposed formulation allows us to relate the permeability properties of an open-cell foam to its morphology alone, without any dependence on the properties of the fluid adopted or on the effective characteristic dimension of the foam micro-structure (pore or cell size). Comparison with experimental results available in the literature is also provided for one of the cases studied

  13. On the characteristics of aerosol indirect effect based on dynamic regimes in global climate models

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, S.; Wang, Minghuai; Ghan, Steven J.; Ding, A.; Wang, Hailong; Zhang, Kai; Neubauer, David; Lohmann, U.; Ferrachat, S.; Takeamura, Toshihiko; Gettelman, A.; Morrison, H.; Lee, Y. H.; Shindell, D. T.; Partridge, Daniel; Stier, P.; Kipling, Z.; Fu, Congbin

    2016-03-04

    Aerosol-cloud interactions continue to constitute a major source of uncertainty for the estimate of climate radiative forcing. The variation of aerosol indirect effects (AIE) in climate models is investigated across different dynamical regimes, determined by monthly mean 500 hPa vertical pressure velocity (ω500), lower-tropospheric stability (LTS) and large-scale surface precipitation rate derived from several global climate models (GCMs), with a focus on liquid water path (LWP) response to cloud condensation nuclei (CCN) concentrations. The LWP sensitivity to aerosol perturbation within dynamic regimes is found to exhibit a large spread among these GCMs. It is in regimes of strong large-scale ascend (ω500 < -25 hPa/d) and low clouds (stratocumulus and trade wind cumulus) where the models differ most. Shortwave aerosol indirect forcing is also found to differ significantly among different regimes. Shortwave aerosol indirect forcing in ascending regimes is as large as that in stratocumulus regimes, which indicates that regimes with strong large-scale ascend are as important as stratocumulus regimes in studying AIE. 42" It is further shown that shortwave aerosol indirect forcing over regions with high monthly large-scale surface precipitation rate (> 0.1 mm/d) contributes the most to the total aerosol indirect forcing (from 64% to nearly 100%). Results show that the uncertainty in AIE is even larger within specific dynamical regimes than that globally, pointing to the need to reduce the uncertainty in AIE in different dynamical regimes.

  14. Early Warning System in ASEAN Countries Using Capital Market Index Return: Modified Markov Regime Switching Model

    Directory of Open Access Journals (Sweden)

    Imam Wahyudi

    2011-01-01

    Full Text Available Asia's inancial crisis in July 1997 affects currency, capital market, and real market throughout Asian countries. Countries in southeast region (ASEAN, including Indonesia, Malaysia, Philippines, Singapore, and Thailand, are some of the countries where the crisis hit the most. In these countries, where inancial sectors are far more developed than real sectors and the money market sectors, most of the economic activities are conducted in capital market. Movement in the capital market could be a proxy to describe the overall economic situation and therefore the prediction of it could be an early warning system of economic crises. This paper tries to investigate movement in ASEAN (Indonesia, Malaysia, Philippines, Singapore, and Thailand capital market to build an early warning system from inancial sectors perspective. This paper will be very beneicial for the government to anticipate the forthcoming crisis. The insight of this paper is from Hamilton (1990 model of regime switching process in which he divide the movement of currency into two regimes, describe the switching transition based on Markov process and creates different model for each regimes. Differ from Hamilton, our research focuses on index return instead of currency to model the regime switching. This research aimed to ind the probability of crisis in the future by combining the probability of switching and the probability distribution function of each regime. Probability of switching is estimated by categorizing the movement in index return into two regimes (negative return in regime 1 and positive return in regime 2 then measuring the proportion of switching to regime 1 in t given regime 1 in t-1 (P11 and to regime 2 in t given regime 2 in t-1 (P22. The probability distribution function of each regime is modeled using t-student distribution. This paper is able to give signal of the 1997/8 crisis few periods prior the crisis.

  15. Analysis of weather condition influencing fire regime in Italy

    Science.gov (United States)

    Bacciu, Valentina; Masala, Francesco; Salis, Michele; Sirca, Costantino; Spano, Donatella

    2014-05-01

    Fires have a crucial role within Mediterranean ecosystems, with both negative and positive impacts on all biosphere components and with reverberations on different scales. Fire determines the landscape structure and plant composition, but it is also the cause of enormous economic and ecological damages, beside the loss of human life. In addition, several authors are in agreement suggesting that, during the past decades, changes on fire patterns have occurred, especially in terms of fire-prone areas expansion and fire season lengthening. Climate and weather are two of the main controlling agents, directly and indirectly, of fire regime influencing vegetation productivity, causing water stress, igniting fires through lightning, or modulating fire behavior through wind. On the other hand, these relationships could be not warranted in areas where most ignitions are caused by people (Moreno et al. 2009). Specific analyses of the driving forces of fire regime across countries and scales are thus still required in order to better anticipate fire seasons and also to advance our knowledge of future fire regimes. The objective of this work was to improve our knowledge of the relative effects of several weather variables on forest fires in Italy for the period 1985-2008. Meteorological data were obtained through the MARS (Monitoring Agricultural Resources) database, interpolated at 25x25 km scale. Fire data were provided by the JRC (Join Research Center) and the CFVA (Corpo Forestale e di Vigilanza Ambientale, Sardinia). A hierarchical cluster analysis, based on fire and weather data, allowed the identification of six homogeneous areas in terms of fire occurrence and climate (pyro-climatic areas). Two statistical techniques (linear and non-parametric models) were applied in order to assess if inter-annual variability in weather pattern and fire events had a significant trend. Then, through correlation analysis and multi-linear regression modeling, we investigated the

  16. Robustness and uncertainties in future hydrological regimes of Swiss catchments

    Science.gov (United States)

    Addor, N.; Roessler, O.; Koeplin, N.; Bernhard, L.; Weingartner, R.; Seibert, J.

    2013-12-01

    Projections of discharge under future climate are impaired by uncertainties arising from different sources: the emission scenarios, the climate models and internal climate variability, the post-processing and sampling of the climate projections, and the hydrological models structure and parameterization. This study aims to investigate the contribution of these sources to the final uncertainty of discharge projections. To this end we performed analyses of variance (ANOVA) in six catchments expected to react differently to climate change and representative of the typical Swiss discharge regimes. We used climate projections of the CH2011 dataset obtained from the Center for Climate Systems Modeling (C2SM). This dataset consists of two types of projections, both relying on the delta change technique. The delta coefficients were determined either in a deterministic way by spectral smoothing of 10 GCM-RCM chains or in a probabilistic way by a Bayesian multi-model approach combining 20 runs until 2050, and then 14 runs until 2099. In addition to the climate projections for emission scenario A1B chosen for the ENSEMBLES project, the CH2011 team generated simulations for the scenarios A2 and RCP3PD using pattern scaling. This enabled us to address the influence of the uncertainty in greenhouse gas emissions on discharge projections. We ran hydrological simulations using three conceptual models: HBV, PREVAH and WaSiM. HBV and PREVAH rely on a similar reservoir structure, while WaSiM uses the more process-oriented Richards-equation approach. PREVAH and WaSiM rely on a higher level of spatial discretization than the lumped HBV model. The use of the three different models allowed evaluation of the sensitivity of discharge projections to the hydrological model complexity and structure. Further, we compared two ways to determine PREVAH parameter values: via calibration and via regionalization. Simulations were run for the periods 2020-2049, 2045-2074 and 2070-2099 to assess the

  17. An Interface between Law and Science: The Climate Change Regime

    Science.gov (United States)

    Kuleshov, Y.; Grandbois, M.; Kaniaha, S.

    2012-04-01

    Law and Science are jointly building the international climate change regime. Up to date, international law and climate science have been unable to take into consideration both regional law and Pacific climate science in this process. Under the International Climate Change Adaptation Initiative (the Australian Government Initiative to assist with high priority climate adaptation needs in vulnerable countries in the Asia-Pacific region) significant efforts were dedicated to improve understanding of climate in the Pacific through the Pacific Climate Change Science Program (PCCSP) and through the Pacific Adaptation Strategy Assistance Program (PASAP). The first comprehensive PCCSP scientific report on the South Pacific climate has been published in 2011. Under the PASAP, web-based information tools for seasonal climate prediction have been developed and now outputs from dynamical climate model are used in 15 countries of the North-West and South Pacific for enhanced prediction of rainfall, air and sea surface temperatures which reduces countries' vulnerability to climate variability in the context of a changing climate. On a regional scale, the Meteorological and Geohazards Department of Vanuatu is preparing a full report on Climate change impacts on the country. These scientific reports and tools could lead to a better understanding of climate change in the South Pacific and to a better understanding of climate change science, for lawyers and policy-makers. The International climate change regime develops itself according to science findings, and at the pace of the four scientific reports issued by the Intergovernmental Panel on Climate Change (IPCC). In return, Law is a contributing factor to climate change, a structural data in the development and perception of environmental issues and it exerts an influence on Science. Because of the dependency of law on science, the PCCSP and PASAP outcomes will also stimulate and orientate developments in law of the Pacific

  18. Zonal flow regimes in rotating anelastic spherical shells (Invited)

    Science.gov (United States)

    Gastine, T.; Wicht, J.; Aurnou, J. M.; Heimpel, M. H.

    2013-12-01

    The surface zonal winds observed in the giant planets form a complex jet pattern with alternating prograde and retrograde direction. While the main equatorial band is prograde on the gas giants, both ice giants have a pronounced retrograde equatorial jet. The depth of these jets is however poorly known and highly debated. Theoretical scenarios range from "shallow models", that assume that these zonal flows are restricted to the outer stably stratified layer; to "deep models" that hypothesise that the surface winds are the signature of deep-seated convection. Most of the numerical models supporting the latter idea employed the Boussinesq approximation where compressibility effects are ignored. While this approximation is suitable for modelling the liquid iron core of terrestrial planets, this becomes questionable in the gas giants interiors, where density increases by several orders of magnitude. To tackle this problem, several numerical models using the "anelastic approximation" have been recently developed to study the compressibility effects while filtering out the fast acoustic waves. Here, we consider such anelastic models of rapidly-rotating spherical shells to explore the properties of the zonal winds in different regimes where either rotation or buoyancy dominates the force balance. We conduct several parameter studies to quantify the dependence of zonal flows on the background density stratification and the driving of convection. We find that the direction of the equatorial wind is controlled by the ratio of buoyancy and Coriolis force. The prograde equatorial band maintained by Reynolds stresses is found in the rotation-dominated regime. At low Ekman numbers, several alternating jets form at high latitude in a similar way to some previous Boussinesq calculations. In cases where buoyancy dominates Coriolis force, the angular momentum per unit mass is homogenised and the equatorial band is retrograde, reminiscent to those observed in the ice giants

  19. The thermal regime around buried submarine high voltage cables

    Science.gov (United States)

    Emeana, C. J.; Hughes, T. J.; Dix, J. K.; Gernon, T. M.; Henstock, T. J.; Thompson, C. E. L.; Pilgrim, J. A.

    2016-05-01

    The expansion of offshore renewable energy infrastructure and the need for trans-continental shelf power transmission require the use of submarine High Voltage (HV) cables. These cables have maximum operating surface temperatures of up to 70°C and are typically buried 1-2 m beneath the seabed, within the wide range of substrates found on the continental shelf. However, the heat flow pattern and potential effects on the sedimentary environments around such anomalously high heat sources in the near surface sediments are poorly understood. We present temperature measurements from a 2D laboratory experiment representing a buried submarine HV cable, and identify the thermal regimes generated within typical unconsolidated shelf sediments-coarse silt, fine sand and very coarse sand. We used a large (2 × 2.5 m) tank filled with water-saturated spherical glass beads (ballotini) and instrumented with a buried heat source and 120 thermocouples, to measure the time-dependent 2D temperature distributions. The observed and corresponding Finite Element Method (FEM) simulations of the steady state heat flow regimes, and normalised radial temperature distributions were assessed. Our results show that the heat transfer and thus temperature fields generated from submarine HV cables buried within a range of sediments are highly variable. Coarse silts are shown to be purely conductive, producing temperature increases of >10°C up to 40 cm from the source of 60°C above ambient; fine sands demonstrate a transition from conductive to convective heat transfer between c. 20°C and 36°C above ambient, with >10°C heat increases occurring over a metre from the source of 55°C above ambient; and very coarse sands exhibit dominantly convective heat transfer even at very low (c. 7°C) operating temperatures and reaching temperatures of up to 18°C above ambient at a metre from the source at surface temperatures of only 18°C. These findings are important for the surrounding near surface

  20. The thermal regime around buried submarine high-voltage cables

    Science.gov (United States)

    Emeana, C. J.; Hughes, T. J.; Dix, J. K.; Gernon, T. M.; Henstock, T. J.; Thompson, C. E. L.; Pilgrim, J. A.

    2016-08-01

    The expansion of offshore renewable energy infrastructure and the need for trans-continental shelf power transmission require the use of submarine high-voltage (HV) cables. These cables have maximum operating surface temperatures of up to 70 °C and are typically buried 1-2 m beneath the seabed, within the wide range of substrates found on the continental shelf. However, the heat flow pattern and potential effects on the sedimentary environments around such anomalously high heat sources in the near-surface sediments are poorly understood. We present temperature measurements from a 2-D laboratory experiment representing a buried submarine HV cable, and identify the thermal regimes generated within typical unconsolidated shelf sediments—coarse silt, fine sand and very coarse sand. We used a large (2 × 2.5 m2) tank filled with water-saturated spherical glass beads (ballotini) and instrumented with a buried heat source and 120 thermocouples to measure the time-dependent 2-D temperature distributions. The observed and corresponding Finite Element Method simulations of the steady state heat flow regimes and normalized radial temperature distributions were assessed. Our results show that the heat transfer and thus temperature fields generated from submarine HV cables buried within a range of sediments are highly variable. Coarse silts are shown to be purely conductive, producing temperature increases of >10 °C up to 40 cm from the source of 60 °C above ambient; fine sands demonstrate a transition from conductive to convective heat transfer between cf. 20 and 36 °C above ambient, with >10 °C heat increases occurring over a metre from the source of 55 °C above ambient; and very coarse sands exhibit dominantly convective heat transfer even at very low (cf. 7 °C) operating temperatures and reaching temperatures of up to 18 °C above ambient at a metre from the source at surface temperatures of only 18 °C. These findings are important for the surrounding near