Top PDF Statistics of vertical backscatter profile of cirrus clouds

Statistics of vertical backscatter profile of cirrus clouds

Statistics of vertical backscatter profile of cirrus clouds

Current lidars can sense scattering layers with visible OD lower than about 3. Un- til few years ago, these instruments were mostly ground-based and thus only scat- tering layers at the zenith of the measuring site could be observed. When high clouds are studied using lidar observations, the up-looking measurement configura- tion shows some disadvantages: both low-level clouds and thick aerosol layers at-

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Modelling of cirrus clouds – Part 2: Competition of different nucleation mechanisms

Modelling of cirrus clouds – Part 2: Competition of different nucleation mechanisms

When heterogeneous ice nuclei are present in the ISSR, cloud evolution changes significantly. Now, the first crys- tals form by heterogeneous nucleation at t s ∼ 60 min. These ice crystals find a highly supersaturated environment with much less competition for the excess vapour than ice crys- tals formed homogeneously, because of the low number con- centration of IN. Thus they rapidly grow and start to fall which causes a vertical concentration gradient of ice in the ISSR, i.e. more ice at ISSR base than at its top. Thus the rate at which excess vapour is consumed due to ice growth decreases with altitude in the ISSR and the originally rectan- gular humidity profile gets more and more tilted with values increasing with altitude before homogeneous nucleation sets in. The tilting is additionally supported by the temperature dependent growth of ice crystals. The change of the RHi profile is the stronger the more IN are present (see Fig. 3) and it affects the homogeneous nucleation event and the later cloud evolution. While homogeneous nucleation takes place over the whole depth of the ISSR when no IN are present, the inclusion of more and more IN confines the region where ho- mogeneous nucleation can occur more and more to the cloud top.
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Arctic stratospheric dehydration – Part 2: Microphysical modeling

Arctic stratospheric dehydration – Part 2: Microphysical modeling

Abstract. Large areas of synoptic-scale ice PSCs (po- lar stratospheric clouds) distinguished the Arctic winter 2009/2010 from other years and revealed unprecedented ev- idence of water redistribution in the stratosphere. A unique snapshot of water vapor repartitioning into ice particles was obtained under extremely cold Arctic conditions with tem- peratures around 183 K. Balloon-borne, aircraft and satellite- based measurements suggest that synoptic-scale ice PSCs and concurrent reductions and enhancements in water va- por are tightly linked with the observed de- and rehydra- tion signatures, respectively. In a companion paper (Part 1), water vapor and aerosol backscatter measurements from the RECONCILE (Reconciliation of essential process parame- ters for an enhanced predictability of Arctic stratospheric ozone loss and its climate interactions) and LAPBIAT-II (La- pland Atmosphere–Biosphere Facility) field campaigns have been analyzed in detail. This paper uses a column version of the Zurich Optical and Microphysical box Model (ZOMM) including newly developed NAT (nitric acid trihydrate) and ice nucleation parameterizations. Particle sedimentation is calculated in order to simulate the vertical redistribution of chemical species such as water and nitric acid. Despite lim- itations given by wind shear and uncertainties in the ini- tial water vapor profile, the column modeling unequivocally
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Elastic-backscatter-lidar-based characterization of the convective boundary layer and investigation of related statistics

Elastic-backscatter-lidar-based characterization of the convective boundary layer and investigation of related statistics

It is important to mention here that in contrast to the quasi- continuous CBL, presence of different aerosol layers, a rapid growth of the CBL in the morning and a high non-stationarity during Case II made the distributions of the higher-order statistics in the CBL rather complicated so that the interpre- tation of the results was not straightforward. A major dif- ficulty may arise if turbulent variables are compared with CBL similarity relationships and turbulent scales which are only defined in a quasi-stationary CBL; hence such compar- ison should be strictly avoided for Case II. Additionally, a detailed discussion on the turbulence profiles in the regions of RL and AL was not possible due to lack of resolution in our measurements and presence of waves. The analysis pre- sented here can be improved if more information concerning the vertical profile of aerosol microphysical properties be- comes available, e.g., by in-situ profiling or the application of multi-wavelength lidar systems. In future, we will com- bine aerosol backscatter measurements with water-vapor and temperature lidar measurements to detail more insights into the RH dependencies of particle backscatter coefficient. Cli- matology of these variables, e.g., collected with operational lidar system such as the SGP Raman lidar (Wulfmeyer et al., 2010) will be beneficial to characterize turbulence features in different regimes of CBL.
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Balloon-borne match measurements of mid-latitude cirrus clouds

Balloon-borne match measurements of mid-latitude cirrus clouds

Fig. 11. Detailed microphysics runs with column spectral model based on the original COSMO- 7 analysis fields with superimposed small-scale temperature fluctuations: (a) Relative humidity with respect to ice; (b) ice crystal number density; (c) ice mixing ratio (defined as number of water molecules condensed in ice per number of air molecules); (d) aerosol backscatter ratio (870 nm wavelength). Green lines: flight tracks of balloons launched from Payerne (“PA”) and Zurich (“ZU”). Black lines: positions shifted by half hour upstream (to compensate for a COSMO warming phase error). Thin vertical stripes in RH ice reveal the (dT / dt) ss superimposed on the adiabatic trajectories based on COSMO fields. All sky conditions are assumed for the small- scale temperature fluctuations, mass accommodation coefficient of H 2 O on ice is a function of
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The vertical distribution of aerosols, Saharan dust and cirrus clouds in Rome (Italy) in the year 2001

The vertical distribution of aerosols, Saharan dust and cirrus clouds in Rome (Italy) in the year 2001

Summer (JJA) conditions show a marked lifting of the PBL aerosol upper boundary and an increase in its OT, likely associated to a stronger convection. The threshold extinc- tion value of 0.01 km −1 is now crossed at 3.8 km (ND curve in Fig. 4c) and PBL aerosol OT reaches maximum values of 0.16, as opposed to the winter minimum of 0.08 (e.g. Figs. 4k and i). Nonetheless, a low cirrus activity leads to a total OT of 0.22, i.e. smaller than the spring (0.35) and fall (0.26) ones. In this season, the cirrus contribution (0.03) to the to- tal OT is of 13% (Fig. 4k), the lowest in the record. Figure 4c shows an evident impact of dust on the extinction profile between 2 and 6 km, with a contribution of 0.03 to the total OT. Conversely, the dust (SD) extinction profile in the PBL below 1.7 km is systematically lower than the no-dust (ND) one. This effect (also visible in the MAM case), is possibly due to the warming and consequent stabilization of the PBL air characterizing Saharan events. In no-dust (ND) condi- tions, depolarization in the lower PBL (Fig. 4g) reaches the maximum value of the year (7%), as opposed to minimum winter values of 4% (Fig. 4e). This behavior suggests both a stronger presence of crustal aerosols and a smaller RH-driven growth of soluble particles.
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Particle backscatter and relative humidity measured across cirrus clouds and comparison with state-of-the-art cirrus modelling

Particle backscatter and relative humidity measured across cirrus clouds and comparison with state-of-the-art cirrus modelling

ter sonde COBALD (Compact Optical Backscatter and AerosoL Detector) was flown 14 times together with a CFH (Cryogenic Frost point Hygrometer) from Lindenberg, Germany (52 ◦ N, 14 ◦ E). The case discussed here in detail shows two cirrus layers with in-cloud relative humidities with respect to ice between 50 % and 130 %. Global operational analysis data of ECMWF (roughly 1 ◦ × 1 ◦ horizontal and 1 km vertical res-

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Buying Behavior Of Organic Vegetables Product The Effects Of Perceptions Of Quality And Risk

Buying Behavior Of Organic Vegetables Product The Effects Of Perceptions Of Quality And Risk

products (Kim & Chung, 2011:40), so it’s important to recognize consumer purchasing behavior. Many companies use marketing strategies by analyzing consumer behavior in order to study the effect on purchase decision (Jalalkamali & Nikbin, 2010:235). The purchase decision is also influenced by the perceived quality which is also an aspect of brand value that makes consumers pay for certain products or services (Yaseen et al., 2011:833). It confirms that the consumer purchase decision on products or services is strongly influenced by customer perception of quality of value brand. Decision making is a way of choosing between two or more possible options when a person has a choice between purchasing or not (Schiffman & Kanuk, 2007). In the assessment stages of different choices, the consumers classify different brands and the purchase intention is created in his mind. Shareef et al. (2008) revealed purchase decision is a continuous process, which refers to thoughtful, consistent action undertaken to bring about need satisfaction. Choubtarash et al. (2013) confirmed that purchase decision is a person in the mind who is carefully analyzing the features of products, trademarks or services and tries, by using logical methods, to choose a choice that can satisfy the recognized need with the least expenses. Consumers perceived organic as a healthier alternative to conventional foods in that they contain more nutrients which enhance personal well-being organic produce is also considered safer and better in taste and more enjoyable than conventional products (Shaharudin et al., 2010:72). Last organic purchasing is defined as purchasing goods and services which have less harmful for environmental and human health (Othman & Rahman, 2014:93). Purchasing decisions can be measured through several dimensions, including recommend, purchase frequency, overall satisfaction and purchase intention (Shareef et al., 2008:101). The measure is not different from the study by Liu et al. (2009:72) which provide specifications for purchasing decisions by some measures, including product selection, brand selection, object selection, purchase opportunity, and purchase quantity. Consumer purchasing decisions on products had relationship with consumer perceptions of quality and risk products (Yee et al., 2011:47). Consumer interest in the products can be improved by an increase in the quality of products (Kwak & Kang, 2009:85). And previous research has argued that a consumer perception of quality has a positive impact on consumer buying behavior (Wang & Tsai, 2014:27). Based on these studies, next hypothesis as follows:
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Influence of supply voltage frequency of induction coil on inoculation efficiency of pure aluminium structure

Influence of supply voltage frequency of induction coil on inoculation efficiency of pure aluminium structure

Moreover, increase in refinement of aluminium structure results from influence of rotate electromagnetic field on liquid metal in time of its solidification in mould. However in this case effectiveness of inoculation fundamentally depends on value of frequency of supply voltage feeding induction coil, which generates electromagnetic field. Application of frequency of supply voltage f 50 Hz does not guarantee favourable transformation of pure aluminium structure. Whereas induction coil fed with frequency of supply voltage larger than power network i.e. 75 Hz or mainly 100 Hz, generates rotate electromagnetic field, which guarantees favourable refinement of structure from point of view of assumed criterion of minimum value of factor R (Tab. 2 and Fig. 6c). In this case value of factor R is more favourable in comparison with value obtained for aluminium after Ti and B inoculation and after common influence of both modifying factors.
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The Influence of Small Amounts of Aluminium on the Spheroidization of Cast Iron with Cerium Mischmetal

The Influence of Small Amounts of Aluminium on the Spheroidization of Cast Iron with Cerium Mischmetal

Introduction of aluminium in the quantity of either about 0.6% (the alloy from melt No. 1) or about 1.1% (the alloy from melt No. 2) leads to the arising of the ferrite-pearlite matrix containing the precipitates of free cementite despite the significant silicon content in the cast iron (see data in Table 4 and Figs 2 and 4). The cast iron from these two melts did not contain the regular nodular graphite precipitates. In both cases the shape of graphite precipitates, according to the Standard [15], can be classified as II, its distribution as B, magnitude as 6 (see Figs 1 and 3).
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Determination Of Longevity Of Teeth In Buckets Of Loading Equipment In Coal Mines - A Case Study

Determination Of Longevity Of Teeth In Buckets Of Loading Equipment In Coal Mines - A Case Study

device was studied. The study took into account the effects of machine scale, wear surface structure of the rolls, grinding pressures and rolls speed, gap settings, feed size distribution and moisture content for a range of ores. The authors proposed a prevailing wear mechanism and a methodology for minimising wear of the grinding rolls, specific to the high pressure grinding device only. An example of a direct method, Bond (1964) and Buchi (1995) developed testing apparatus that determine rock abrasiveness in a low abrasion/medium impact mode of wear where rock abrasiveness is measured as the amount of material lost by a standard steel paddle which rotates on a shaft in a sample of loose rock particles of a certain specified size range. As can be seen from the above examples, the indirect methods of rock abrasivity assessment have the advantage of using data which is either readily available or relatively straightforward to obtain. However, they do not take into account process variables for specific modes of wear. Hence, they are normally not used in isolation, but rather in combination with direct methods, or holistic approaches, to supplement or confirm other more relevant direct measures. However, there is no universally accepted one standard test to determine the rock abrasivity although a large number of different tests are in use. All the studies about rock abrasiveness are concentrated on the amount of quartz, grain size and cementation degree of quartz, the geometry of the abrasive mineral and mechanical strength of rock.
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Evaluation of susceptibility of the ZRE1 alloy to hot cracking in conditions of forced strain

Evaluation of susceptibility of the ZRE1 alloy to hot cracking in conditions of forced strain

Nowadays, magnesium alloys are used for casting into sand moulds of huge dimensional castings, high-pressure castings and precise casings. In castings of magnesium alloys defects or inconsistencies often appear (like casting misrun, porosities and cracks) particularly in the huge dimensional castings. Such defects are mended with the use of padding and welding. The welding techniques can be applied by using weld material consisting of magnesium alloy, as well as for regeneration of alloys after excessive wear. Nevertheless, the number of the repaired castings, which were permitted for use, is not satisfactory for a profitable production. The main reasons for wear are the cracks appearing during welding in brittleness high-temperature range.
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Vertical profiles of droplet effective radius in shallow convective clouds

Vertical profiles of droplet effective radius in shallow convective clouds

tion. As shown in many field observations, droplet size not only exhibits horizontal heterogeneity, but also vertical strat- ification (e.g., Warner, 1955; Brenguier et al., 2000; Miles et al., 2000; Hudson and Yum, 2001; Twohy et al., 2005; Jiang et al., 2008; Lu et al., 2008; Arabas et al., 2009). The verti- cal stratification of droplet size must be resolved because it is central to both the cloud albedo and the precipitation pro- cess (Brenguier et al., 2003; Rosenfeld and Lensky, 1998). Although in situ measurements can resolve vertical profiles of droplet size, they cannot provide regional or global scale data sets for understanding and parameterization of aerosol effects on climate. Robust and widely applicable methods are needed for retrieving profiles of cloud droplet r e . Ground-
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SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

SOCIAL ECONOMY – A FORM OF INCLUSION AND OF ''REACTIVATING'' OF LABOR IN THE CONTEXT OF THE CURRENT CRISIS

Despite the exigencies of the European Union regarding the active inclusion , which means to ensure labor markets for those looking for a job and for the disadvantaged persons , in several countries Greece, Ţortugal, Romania, etc. some passive policies were promoted, resource consuming, outside the system of social economy, that have aggravated the local crises and have extended the global crisis of the current society European Commission , p. .

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Evaluating the influence of selected parameters on sensitivity of a numerical model of solidification

Evaluating the influence of selected parameters on sensitivity of a numerical model of solidification

Presented paper contains evaluation of influence of selected parameters on sensitivity of a numerical model of solidification. The investigated model is based on the heat conduction equation with a heat source and solved using the finite element method (FEM). The model is built with the use of enthalpy formulation for solidification and using an intermediate solid fraction growth model. The model sensitivity is studied with the use of Morris method, which is one of global sensitivity methods. Characteristic feature of the global methods is necessity to conduct a series of simulations applying the investigated model with appropriately chosen model parameters. The advantage of Morris method is possibility to reduce the number of necessary simulations. Results of the presented work allow to answer the question how generic sensitivity analysis results are, particularly if sensitivity analysis results depend only on model characteristics and not on things such as density of the finite element mesh or shape of the region. Results of this research allow to conclude that sensitivity analysis with use of Morris method depends only on characteristic of the investigated model.
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Statistical Assessment of the Effect of Chemical Composition on Mechanical Properties of Hypereutectic AlSi17CuNiMg Silumin

Statistical Assessment of the Effect of Chemical Composition on Mechanical Properties of Hypereutectic AlSi17CuNiMg Silumin

The paper presents a statistical assessment of the effect of chemical composition on mechanical properties of hypereutectic AlSi17 silumin, which is expected to act as a counterpart of alloys used by automotive industry and aviation for casting of high-duty engine parts in West European countries and USA. The studies on the choice of chemical composition of silumins were preceded by analysis of the reference literature to state what effect some selected alloying elements and manufacturing technology may have on the mechanical properties (HB, R m and A 5 ) of these alloys. As alloying additives, Cu, Ni and Mg in proper combinations were used. The alloy after
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Effect of water glass modification with nanoparticles of zinc oxide on selected physical and chemical properties of binder and mechanical properties of sand mixture

Effect of water glass modification with nanoparticles of zinc oxide on selected physical and chemical properties of binder and mechanical properties of sand mixture

In this study, an attempt was made to carry out the modification of water glass with zinc nanoxide. The aim of the research was to determine what effect the modifier added to binder may have on the wettability of quartz sand grains and on the mechanical properties of the resulting moulding sand mixture.

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The modification process of AlSi21CuNi silumin and its effect on change of mechanical properties of the alloy

The modification process of AlSi21CuNi silumin and its effect on change of mechanical properties of the alloy

Due to difficulties present during machining operations and with segregation of crystals of primary silicon, hypereutectic silumins can be used after modification only. It is why elaboration of effective modification methods is necessary for complete utilization of such alloys for machinery parts made from castings. In the paper are presented test results concerning an effect of modification with phosphor copper and strontium of AlSi21CuNi silumin on change of its mechanical properties (R B m B , A B 5 B ) and its structure. Investigated alloy was melted in
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Fuel Conservation Strategies for the Vertical Profile of Cruise Flight

Fuel Conservation Strategies for the Vertical Profile of Cruise Flight

The flight plan can be modified at any time, whether from a crew decision, from an airline operational communication or by air traffic control due to a tactical situation. An edition of the flight plan creates a temporary modified version that is a copy of the active flight plan plus all the changes made to it. To allow the crew to assess the impact of the flight plan changes, trajectory predictions are calculated for every edit on the modified FPLN and periodically updated. When all the changes are in accordance with the crew's will, a FPLN change approval from the ATCo is needed is order to make it an active FPLN. During the negotiation phase, the ATCo will assess the consequences of the proposed FPLN changes, the ATCo can then accept or reject the required modifications. When the FPLN modification is accepted by the ATCo, the modified flight plan is activated by the crew in the FMS.
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Estimating Sample Size of Soil Cone Index Profiles by Bootstrapping

Estimating Sample Size of Soil Cone Index Profiles by Bootstrapping

The raw CI data (302 profiles) were pre-processed to eliminate systematic errors of soil penetrometer measurements. The distribution of CI values was summarized per layer using descriptive statistics and boxplots. Forty CI profiles were excluded prior to data analysis because they contained observations that exceeded the three-fold interquartile range from the first and third quartiles or were regarded as technical artifacts of the soil penetrometer measurements, such as reading failures. Data normality was assessed by the Shapiro-Wilks normality test per layer, and logarithmic transformation was performed if needed. The spatial autocorrelation of CI readings was examined by computing sample variograms in horizontal and vertical directions. Because of the non-stationarity of CI along the vertical direction, a polynomial model was developed using soil depth as explanatory variable. The trend coefficients were estimated by the generalized least squares (GLS) method and the sample variogram was computed using GLS residuals (Webster and Oliver, 2007).
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