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Owing to the rapid development of LSI technology in recent years, it has become easy to realize digital filters with custom LSIs. Presently, most digital filters are realized using fixed-point arithmetic. Because fixed-point arithmetic has a narrow dynamic range, it is important to suppress overflow. Moreover, the multiplier is a large circuit component in digital filters. If we choose an IIR digital filter for amplitude characteristic realization, the filter order may be low and the circuit scale could be reduced. The elliptic type filter is the most common type of IIR digital filter. Therefore, we will consider a digital elliptic filter with fixed- point arithmetic in this paper. First, in designing the digital filter, it is important to know the dynamic range required in implementation. The gain constant of a digital filter is important when estimating the required dynamic range. Next, in cascade form digital filter, the gain constant has to be distributed to each second-order section to prevent overflow under operation. In this paper, we show a simple method of estimating the gain constant from filter designing parameters; filter order, pass band ripple, pass band edge frequency and transition band width. And we confirm the effectiveness of the method. Next, we show a simple and high precision method to distribute the gain constant to each second-order section.

— The enthalpy of formation of a binary oxide compound is roughly a function of the enthalpy of the oxides and ions involved in its composition. The enthalpies are estimated by the so called corresponding state method. The model is improved by using index of refraction, molecular volume and polarizability, as well as cation-oxygen bond length in the compound and in its corresponding oxides. This approach has been applied to solid solutions by using a ternary regular solid solution model. Two series of compounds Mg₂SiO₄₋Ni₂SiO₄ and Fe₂SiO₄₋Ni₂SiO₄ are studied in this paper ; the variations of energies due to differences in surrounding cations explains the deviations in enthalpy of mixing from the regular functions. Assuming that the enthalpy of mixing is independent of temperature, Gibbs free, L'enthalpie de formation apparaît tout d'abord comme une fonction de l'enthalpie de formation des oxydes et des ions qui entrent dans leur composition. L'enthalpie de formation des minéraux est estimée par la méthode des états correspondants. Le calcul de l'enthalpie est ensuite affiné en utilisant l'indice de réfraction, le volume moléculaire, la polarisabilité ainsi que les distances cation-oxygène dans le minéral et dans les oxydes correspondants. Cette approche a été appliquée aux solutions solides en utilisant un modèle de solution solide ternaire et régulière. En étudiant deux solutions solides Mg₂SiO₄₋Ni₂SiO₄ and Fe₂SiO₄₋Ni₂SiO₄, on montre que les variations d'environnements des différents cations se traduisent par des irrégularités d'enthalpie qui s'ajoutent ou se retranchent à la courbe régulière d'excès d'enthalpie de mélange. En supposant que l'enthalpie de mélange est indépendante de la température, les enthalpies libres de mélange sont calculées et comparées avec la littérature., Vieillard Philippe, Lamarche Antoine. Predicted excess enthalpies of mixing of (Fe, Ni) olivine and (Mg,Ni) olivine based on refined crystal structures. Evaluation des enthalpies de mélange des solutions solides (Fe, Ni) olivine et (Mg, Ni) olivine à partir de leurs structures cristallines. In: Sciences Géologiques. Bulletin, tome 42, n°4, 1989. Thermodynamique des processus naturels. Thermodynamics of natural processes pp. 351-364.

In case of a Cobb-Douglas production function, the feasible estimation of return to scale is restricted both by the type of output growth and by the type of collinearity which occur during the estimation process. In this context, it is defined the indicator “Reference value of returns to scale” in order to surpass difficulties generated especially by harmful collinearity. Having in mind the above-mentioned indicator, it is proposed an analysis methodology in order to emphasize the role of proper elasticities of the output related to production factors, on the one hand, and the impact of type of collinearity in obtaining the estimated returns to scale, on the other hand. The proposed analysis methodology is practically used by considering statistical data related to a bi- decennial cycle of Romania's economy evolution.

A lidar method is presented that permits the estimation of height profiles of ice nuclei concentrations (INC) in desert dust layers. The polarization lidar technique is applied to separate dust and non-dust backscatter and extinction coefficients. The desert dust extinction coefficients σd are then converted to aerosol particle number concentrations APC280 which consider particles with radius > 280 nm only. By using profiles of APC280 and ambient temperature T along the laser beam, the profile of INC can be estimated within a factor of 3 by means of APC-T-INC parameterizations from the literature. The observed close relationship between σd at 500 nm and APC280 is of key importance for a successful INC retrieval. We studied this link by means of AERONET (Aerosol Robotic Network) sun/sky photometer observations at Morocco, Cabo Verde, Barbados, and Cyprus during desert dust outbreaks. The new INC retrieval method is applied to lidar observations of dust layers with the spaceborne lidar CALIOP (Cloud Aerosol Lidar with Orthogonal Polarization) during two overpasses over the EARLINET (European Aerosol Research Lidar Network) lidar site of the Cyprus University of Technology (CUT), Limassol (34.7° N, 33° E), Cyprus. The good agreement between the CALIOP and CUT lidar retrievals of σd, APC280, and INC profiles corroborates the potential of CALIOP to provide 3-D global desert dust APC280 and INC data sets.

A general method is described which allows a production activity to be analyzed by means of input data only. According to duality theory, the input cost shares can be completely specified without any information about output if the technology is homothetic. It is demonstrated that these cost shares can yield information about elasticities of substitution and factor demand and on productivity development. Moreover, the system of share equations can be generalized to allow for technical and allocative inefficiency and the effects of these inefficiencies on total costs and input demands can be estimated.

The feeding value of maize silage, which is equal to the product of the voluntary intake by the digestibility, is the main factor influencing the performance of livestock. It is necessary to study the sources of its variation and show the factors responsible for the quality of forage maize in order to breed to-morrow's cultivars. For 34 years, from 1958 to 2002, 2383 measurements of digestibility of maize silage were carried out on 478 hybrids at the INRA station in Lusignan. These measurements, made with standard castrated rams, concerned all types of hybrids : early heading, late heading, registrated, experimental, and also bm3 mutants. Results show a very large variation in the energy value of the silages, linked to the hybrid utilized, and under the strong influence of cell-wall digestibility (CUDndf). On average, the energy value of maize is 0.89 UFL (fodder unit fort milk), but the measured values ranged from 0.74 to 1.01 UFL. Various comparisons showed for instance that the early-heading hybrids are more digestible than the late heading ones, and that the more recent cultivars are on average less digestible than the old ones. Lastly, new tools for the prediction of the in vivo digestibility of the organic matter, or of the NDF, should give the breeders the possibility of creating cultivars with better feeding values.; L'ensilage de maïs est largement utilisé pour l'alimentation des ruminants à haut potentiel ; sa valeur alimentaire est le principal facteur influençant les performances des animaux. L'étude des sources de variation et la mise en évidence des critères qui conditionnent la qualité des maïs fourragers est nécessaire pour sélectionner les variétés de demain. Pendant 34 ans, 2 383 mesures de digestibilité d'ensilages de maïs portant sur 478 hybrides ont été réalisées à l'INRA de Lusignan. Ces mesures avec moutons castrés standards ont porté sur tous les types d'hybrides : précoces, tardifs, inscrits, expérimentaux ou encore mutants bm3. La variabilité de la valeur énergétique des ensilages est très importante et elle est fortement conditionnée par la digestibilité des parois (CUDndf). Si le maïs a une valeur énergétique moyenne de 0,89 UFL, les valeurs mesurées vont de 0,74 à 1,01 UFL. Les hybrides précoces sont plus digestibles que les hybrides tardifs ; les variétés récentes sont en moyenne moins digestibles que les variétés anciennes. Enfin, la mise au point d'outils de prédiction de la digestibilité in vivo de la matière organique ou du NDF, utilisables en routine, devraient permettre aux sélectionneurs de proposer des variétés avec des valeurs alimentaires plus élevées.

Global estimates of the elastic thickness (Te) of the structure of passive continental margins show wide and varying results owing to the use of different methodologies. Earlier estimates of the elastic thickness of the North Atlantic passive continental margins that used flexural modelling yielded a Te value of ~20-100 km. Here, we compare these estimates with the Te value obtained using orthonormalized Hermite multitaper recovered isostatic coherence functions. We discuss how Te is correlated with heat flow distribution and depth of necking. The E-W segment in the southern study region comprising Nova Scotia and the Southern Grand Banks show low Te values, while the zones comprising the NE-SW zones, viz., Western Greenland, Labrador, Orphan Basin and the Northern Grand Bank show comparatively high Te values. As expected, Te broadly reflects the depth of the 200-400�C isotherm below the weak surface sediment layer at the time of loading, and at the margins most of the loading occurred during rifting. We infer that these low Te measurements indicate Te frozen into the lithosphere. This could be due to the passive nature of the margin when the loads were emplaced during the continental break-up process at high temperature gradients. � Indian Academy of Sciences.

As part of the MIRAGE (MILAGRO) study conducted 7-30 March 2006 in Mexico City and its Metropolitan Area (MCMA), fine particulate matter (PM2.5) was collected using two Tapered Element Oscillating Microbalance (TEOM) systems, and a Partisol instrument at the T1 super-site (Tecamac, State of Mexico). Inorganic analysis was performed on filter-based (PM1, PM2.5-URG) measurements also collected at this site. Measurements from the gravimetric (TEOMs, Partisol) and URG systems were inter-compared with chemical speciation measurements using a Particle Into Liquid Sampler (PILS) and Thermal Optical methods.Mass and chemical balances applied over the first part of the study (11-22 March) showed that a TEOM using a device (SES) which reduces particle-bound water and retains a fraction of semi-volatile compounds (SVM) gives readings ∼30% larger than a conventional TEOM. In the second part of the study (26-30 March), the loss of SVM during TEOM-heated filter collection (both systems) represented a significant fraction of PM2.5 mass due to changes in particle composition. Overall, when nonvolatile nitrate dominated (i.e., when associated with crustal species and not NH4+) and/or sulfate dominates (SO42-/NO3- molar ratio is >1), PM2.5 mass readings are in agreement with those reported for the T1 site if TEOM is using a SES device. However, when volatile nitrate dominates (i.e., NH4NO3) or SO42-/NO3- molar ratio is

To help livestock farmers better manage their grasslands, networks and observatories for grass growth have been established in numerous departments and regions of France. Created by the joint technological network Prairies Demain, the French National Observatory for Grass Growth brings together regional and departmental data on grass growth collected by local organisations. As the observatory was being developed, there was a data homogenisation phase, during which a validation process was put into place. To make any necessary adjustments, the validation process was tested using data from 2017: we validated a database containing 23,000 entries. We present the initial results here. This work will continue with the goal of monitoring changes in grass growth over several years.; L’Observatoire national de la pousse de l’herbe effectue l’agrégation de l’ensemble des données régionales ou départementales réalisées sur la croissance de l’herbe par les structures locales. La méthodologie de développement de cet Observatoire national comporte une phase d’homogénéisation des données, avec la création d’un processus de validation. Ce processus de validation est testé sur la base de données 2017 pour ajuster la démarche. Les premiers résultats obtenus à partir de la base de 23 000 données validées pour l’année2017 sont présentés. Ce travail va se poursuivre pour percevoir l’évolution de la croissance de l’herbe sur plusieurs années.

Aboveground tropical tree biomass and carbon storage estimates commonly ignore tree height (H). We estimate the effect of incorporating H on tropics-wide forest biomass estimates in 327 plots across four continents using 42 656 H and diameter measurements and harvested trees from 20 sites to answer the following questions: 1. What is the best H-model form and geographic unit to include in biomass models to minimise site-level uncertainty in estimates of destructive biomass? 2. To what extent does including H estimates derived in (1) reduce uncertainty in biomass estimates across all 327 plots? 3. What effect does accounting for H have on plot- and continental-scale forest biomass estimates? The mean relative error in biomass estimates of destructively harvested trees when including H (mean 0.06), was half that when excluding H (mean 0.13). Power- and Weibull-H models provided the greatest reduction in uncertainty, with regional Weibull-H models preferred because they reduce uncertainty in smaller-diameter classes (≤40 cm D) that store about one-third of biomass per hectare in most forests. Propagating the relationships from destructively harvested tree biomass to each of the 327 plots from across the tropics shows that including H reduces errors from 41.8 Mg ha−1 (range 6.6 to 112.4) to 8.0 Mg ha−1 (−2.5 to 23.0). For all plots, aboveground live biomass was −52.2 Mg ha−1 (−82.0 to −20.3 bootstrapped 95% CI), or 13%, lower when including H estimates, with the greatest relative reductions in estimated biomass in forests of the Brazilian Shield, east Africa, and Australia, and relatively little change in the Guiana Shield, central Africa and southeast Asia. Appreciably different stand structure was observed among regions across the tropical continents, with some storing significantly more biomass in small diameter stems, which affects selection of the best height models to reduce uncertainty and biomass reductions due to H. After accounting for variation in H, total biomass per hectare is greatest in Australia, the Guiana Shield, Asia, central and east Africa, and lowest in east-central Amazonia, W. Africa, W. Amazonia, and the Brazilian Shield (descending order). Thus, if tropical forests span 1668 million km2 and store 285 Pg C (estimate including H), then applying our regional relationships implies that carbon storage is overestimated by 35 Pg C (31–39 bootstrapped 95% CI) if H is ignored, assuming that the sampled plots are an unbiased statistical representation of all tropical forest in terms of biomass and height factors. Our results show that tree H is an important allometric factor that needs to be included in future forest biomass estimates to reduce error in estimates of tropical carbon stocks and emissions due to deforestation.

This study presents elastically supported Timoshenko column with attached masses for free vibration analysis using fuzzy neural network. Neuro fuzzy frequency estimation (NFEE) models were developed to compute vibration frequencies using fuzzy logic toolbox of software Matlab 7.0. Gaussian membership functions and adaptive neuro fuzzy inference system (ANFIS) were used in NFFE model. Hybrid learning rule was applied for quantifying output variables in NFFE model. Frequency values of column with 1,5 and 10 attached masses were computed. Training sets for NFFE models used transfer matrix method (TMM). During testing of NFFE model, good agreement was observed with results obtained using TMM as reduction in computation effort.

Farmers, faced with circumstances that are changing ever more rapidly, must be able to adapt. We used 22 small dairy farms located in the Brazilian Cerrado to test a method of assessing farm vulnerability. Each farm’s developmental trajectory was retraced from its date of founding. Nine indices were used to assess the vulnerability of the farms’ dairy production systems. They took into account workforce availability, farmer expertise, surface area kept in reserve, technical approaches (stocking rates and feed autonomy), and financial factors. We quantified farm vulnerability during two periods of drought (2007 and 2011). This method can be used by small farms to make the best decisions possible when intensifying dairy production., Les 9 indicateurs quantitatifs proposés pour évaluer la vulnérabilité des systèmes de production laitière de petits éleveurs sont liés à la disponibilité de la main d’œuvre, à la compétence de l’éleveur, aux réserves de surface, à la conduite technique (chargement, autonomie) et aux aspects financiers. La mise en œuvre de la méthode est illustrée dans un échantillon de 22 petits éleveurs du Cerrado brésilien dont la trajectoire de développement a été préalablement reconstituée depuis leur installation. Les résultats sont présentés pour 2 épisodes de sécheresse (2007 et 2011). Cette méthode peut être utilisée pour aider des groupes de petits éleveurs à prendre de meilleures décisions quand ils se lancent dans l’intensification de leur production de lait