924 resultados para index method


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为黄土丘陵区生态安全预警及其建设提供科学依据。【方法】以纸坊沟流域近70年代表年份生态安全态势及影响因子的分析为基础,参考压力-状态-响应(PSR)模型建立农业生态安全预警指标体系。运用层次分析法(AHP)和德尔菲法(Delphi)确定指标权重,采用综合指数法计算生态安全质量值,用演化轴解释生态安全预警模式,定量评价该流域1938~2005年的农业生态安全状况,并预测2015年的发展趋势。【结果】纸坊沟流域1938年处于蓝灯区,无需预警;1958年为黑灯区,需作生态安全恶化速度预警;1975和1985年处于红灯区,需作生态安全较差状态预警;1995年处于黄灯区,2005和2015年继续向良好方向演化,均不需预警,但从发展趋势来看,预计人口密度于2020年左右进入警戒状态。【结论】研究结果与该流域的实际情况相符,该指标体系和生态安全预警模型可以应用于黄土丘陵区。

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With the rapid increase of the number and influence of floating population in China, it is urgently needed to understand the regional types of China's floating population and their spatial characteristics. After reviewing the current methods for identifying regional types of floating population, this paper puts forward a new composite-index identification method and its modification version which is consisted of two indexes of the net migration rate and gross migration rate. Then, the traditional single-index and the new composite-index identification methods are empirically tested to explore their spatial patterns and characteristics by using China's 2000 census data at county level. The results show: (1) The composite-index identification method is much better than traditional single-index method because it can measure the migration direction and scale of floating simultaneously, and in particular it can identify the unique regional types of floating population with large scale of immigration and emigration. (2) The modified composite-index identification method, by using the share of a region's certain type of floating population to the total in China as weights, can effectively correct the over- or under-estimated errors due to the rather large or small total population of a region. (3) The spatial patterns of different regional types of China's floating population are closely related to the regional differentiation of their natural environment, population density and socio-economic development level. The three active regional types of floating population are mainly located in the eastern part of China with lower elevation, more than 800 mm precipitation, rather higher population densities and economic development levels.

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Productivity prediction is very important in the exploration and development of oilfields. Using well log data to predict productivity is a front-line technology, which is key issue in petroleum exploration phase. The essential factors of productivity prediction is building practical models and correcting various causes to improve precision of prediction parameters. Any errors of parameters selections can affect the calculation of productivity prediction; therefore, how to improve research means and calculation accuracy is an important task of productivity prediction. Theory and case examples are deeply and comprehensively studied in the paper. Based on the theory of mud-filtrate invasion and experimental results, the damage of drilling, cementing, perforating,acidizing and fracturing were investigated. The damage depth was quantitatively evaluated by log data, based on this, the processing results of reservoir sensitivity were used to analysis quantitatively the damage of reservoir. The productivity prediction and reservoir damage were initiatively incorporated according to well logging, and the precision of productivity prediction was effectively improved. The method of NMR was explored to calculate the fluid viscosity on the basis of reservoir physical method, and the differences between the two methods were compared in the paper. From the theory fluid flow in porous media, various of theoretical models of production prediction were explored and several practical models were consided, such as productivity index method, improved productivity index method, improved Bearder method, SVM and so on. The characteristic and the application scope of these methods were studied. The inflow productivity and outflow productivity were incorporated and nodal analysis method was used to forecast wellhead yield, thus achieved scientifically production. On the applied background of conventional logging suite, the applying of special items or new logging method which is practical in the research area were studied, the logging suite was further optimized, and the precision of forecast was improved. On the basis of the modeling and the calculation of parameters, these methods were verified and analyzed, and the reconstruct principle was also built for block reservoir. The research block was processed by these methods and compared with testing data. Based on above the research, a technological system which is practical for shaly sand profiles in Shengli Oilfield was built. The system can reach commercialized degree,and satisfied the need of exploration and development of the oilfield.

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Based on field survey, laboratory testing and numerical modeling, engineering characteristics of undisturbed loess and the mechanism of long-runout loess landslides caused by underground water level rise, as well as the formation conditions and spatial distribution of landslides, are systematically studied and analyzed. Loess landslides at south Plateau of Jingyang County are mainly classified as flowslide, slide and fall. Flowslide is the main type characteristic of high velocity, long runout and multi-stages. The steep relief composed of loose structured loess-old aged soil serials and the rise of groundwater table are the predominant conditions for landslides in the study area. To study loess mechanic poperties and loess landslides mechanisims, isotropically and anisotropically consolidated undrained compression(ICU and ACU) tests and constant-deviator-drained compression (CQD) tests were carried out on undisturbed samples. The results of undrained compression tests performed at the in-situ stress level show that the soils are of consistently strain-softening in the stress-strain relations and cause high excess pore pressure. The steady-state line and the potential region of instability are obtained from ICU and ACU test results. A necessary condition for liquefaction is that the soil state initially lies in or is brought into the potential instability region. In addition, a strong strain-softening model is also formed. CQD tests demonstrate that the mobilized friction angle is far less than the steady-state angle and that the soil experiences undrained contractive failure suddenly at very small strains when its stress path during drained loading tries to cross the potential instability region,thus validates the proposed instability region. Based on the location of the region of potential instability and the stress state of slope soil, a method of static liquefaction analysis is proposed for loess landslides caused by rise in groundwater table. Compared with other liquefaction analysis methods, this method overcomes the limitations inherent in conventional slope stability method and undrained brittleness index method. Triaxial tests composed of constant water content (CW) and wetting tests at constant deviator stress are performed on undisturbed unsaturated samples. The stress-strain relation of CW tests takes on strain-hardening behavior; The results of wetting tests at constant deviator stress designed to study the mechanics of failure of unsaturated loess caused by an increase in the degree of saturation (wetting) shows that a contractive failure occurs in the undisturbed samples. On the basis of the above triaxial test results, the initiation of static liquefaction is presented for long-runout loess landslides caused by rise in groundwater table, that is, the loess slope soil gradually transfer from unsaturated to saturated state under the infiltration of irrigation. A contractive failure occurs in the local region at very small strain by increasing the pore-water pressure at constant deviator stresses under drained conditons. It is the contractive failrue resulting from rise of pore pressure that leads to high excess pore pressure in the neighbour soil which reduces shear resistance of soil. The neighbour soils also fail due to the rapid increase in pore-water pressure. Thus a connected failure surface is developed quickly and a flowslide occurs. Based on the saturated-unsaturated seepage theory, transient seepage is computed using the finite element method on loess slope under groundwater table rise. Pore-water pressure distribution for every time step after irrigation are obtained. The phreatic surface in the slope increases with the groundwater table. Pore-water pressure distribution within 8m above the phreatic surface changes very quickly,but the water content and pore water pressure in the region ranging from 8m above the phreatic surface up to ground surface is almost not affected and the matric suction usually is kept at 100~120 kPa. Based on the results of laboratory tests and seepage flow analysis, the development process of loess landslide is modeled considering groundwater table rise. The shearing plastic zone first occurs at the slope toe where the soil is soaked for long term during rise in groundwater table. As irrigation continues, the shearing plastic zone gradually extends to the interior soils, with the results that the tensile plastic zone occurs at the slope crown. As time goes on, both the shearing plastic zone and tensile plastic zone continue to extend. Then a connected plastic zone is formed and fowslide occurs. In comparision to laboratory test results, the results of numerical simulation quite well verify the presented mechanism of static liquefaction of long-runout loess landslides caused by rise in groundwater table.

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The excitation of surface plasmon-polariton (SPP) waveguide modes in subwavelength dielectric ridges deposited on a thin gold film has been characterized and optimized at telecommunication wavelengths. The experimental data on the electromagnetic mode structure obtained using scanning near-field optical microscopy have been directly compared to full vectorial three-dimensional finite element method simulations. Two excitation geometries have been investigated where SPPs are excited outside or inside the dielectric tapered region adjoint to the waveguide. The dependence of the efficiency of the SPP guided mode excitation on the taper opening angle has been measured and modeled. Single-mode guiding and strong lateral mode confinement of dielectric-loaded SPP waveguide modes have been characterized with the near-field measurements and compared to the effective-index method model.

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Quatre-vingt-quinze squelettes humains issus des fouilles archéologiques du cimetière protestant Saint-Matthew (ville de Québec, 1771-1860) ont été étudiés en associant deux aspects de la paléonutrition : la paléochimie et la paléopathologie. Le but de cette recherche est d’explorer la relation entre nutrition et état de santé pour cette population préindustrielle. Des informations directes sur l’alimentation ont été recueillies par l’analyse des isotopes stables du carbone et de l’azote du collagène des os, et des informations indirectes ont été obtenues par une quantification de l’état de santé des individus. Les méthodes paléopathologiques utilisées sont celles de l’« indice de santé » (Steckel et al., 2002) pour la comparaison interpopulationnelle, puis des méthodes comprenant des degrés de sévérité plus précis afin d’étudier les variations intrapopulationnelles. L’analyse de ces données atteste d’un état de santé relativement mauvais par comparaison avec d’autres groupes nord-américains contemporains, malgré une alimentation similaire. Des différences alimentaires ont été observées en fonction des données paléodémographiques (âge, sexe), mettant notamment en évidence une variabilité temporelle dans la réalisation du processus de sevrage. De plus, un régime alimentaire moins riche en ressources C4 (maïs, sucre de canne) et en ressources animales (viande, poissons, produits laitiers) a été constaté pour les enfants entre 2 et 7 ans par rapport aux individus plus vieux. Enfin, une relation possible entre la sévérité de certaines pathologies (cribra orbitalia et périostite) et la consommation des ressources alimentaires en C4 et/ou marines et riches en protéines a été observée.

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Introducción: El tratamiento estándar para los tumores renales localizados es la nefrectomía radical, sin embargo debido a la variación el tamaño del tumor renal en el momento del diagnóstico, se ha reemplazado en algunos casos por la nefrectomía parcial. Objetivo: Este estudio busca comparar el resultado oncológico de la nefrectomía parcial en términos de supervivencia cáncer específica, respecto a la nefrectomía radical, en pacientes mayores de 50 años con carcinoma renal estadio II (T2N0M0) Métodos: Se realizó una revisión sistemática de la literatura, con inclusión de estudios de casos y controles, cohortes y experimentos clínicos aleatorizados incluidos en las bases de datos de MEDLINE , EMBASE y CENTRAL Resultados: La búsqueda inicial emitió un total de 101 resultados, 11 artículos fueron preseleccionados y sólo un artículo cumplió con los criterios de selección; éste se clasificó como nivel de evidencia II. Conclusión: No fue posible concluir su equivalencia oncológica de la nefrectomía radical con la nefrectomía parcial, dado que no hay diseños de estudios que permitan llegar a esta conclusión.

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Construction is an important industry and forms a vital part of national economics in the world. Factors affecting the productivity of the construction industry should be measured appropriately to reflect its development situation and economic performance. The Malmquist index method with a novel decomposition technique is employed to estimate the total factor productivity of the Australian construction industry during the period 1990-2007 and to analyse the factors affecting the technological change in the industry. Research results exemplified by two input variables and one output variable elaborate how construction technology, pure technical efficiency and scale economy take effect in the change of construction productivity. In addition, based on temporal and spatial comparisons, the analysis for construction productivities reveals their changes over time and across the country. Proposals and recommendations are expected to be beneficial for policy making and strategic decisions to improve the performance of the Australian construction industry.

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There is urgent need to consider energy consumption when measuring total-factor productivity in the construction industry. This paper adopts the Malmquist index method to investigate the factors affecting the energy productivity of the Australian construction industry and compares them with those decomposed from the total-factor productivity. An input-oriented distance function and a contemporaneous benchmark technology are employed to develop the data envelopment analysis models. The Malmquist productivity index is decomposed into the technological change, pure technical efficiency change and activity effect to gain comprehensive insights into changes of construction productivity in the Australian states and territories over the past two decades. Research results show that both energy productivity and total-factor productivity improved in Australia, particularly related to technological development. The pure technical efficiency and activity indices changed slightly over time or across regions. This study demonstrates that there exists a linkage between energy productivity and total-factor productivity through their technological and technical efficiency changes. The Australian construction industry could enhance these two productivities by introducing advanced technologies and implementing them efficiently.

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Com a finalidade de esclarecer os efeitos da adição de óleo vegetal e mineral aos acaricidas foi conduzido um ensaio de campo em 1994 no município de Viradouro, SP, utilizando-se de Assist, Triona e Natur'l Óleo, na dosagem de 500 mL por 100 litros de água, adicionados aos acaricidas: pyridaben nas formulações 200 CE e 750 PM, nas dosagens de 75 mL e 20 g; propargite 720 CE a 100 mL; óxido de fenbutatina 500 SC a 80 mL e cyhexatin 500 PM a 50 g. O delineamento estatístico adotado foi o de blocos casualizados. As aplicações foram feitas com pulverizador tipo pistola. Após a preparação da calda, foi determinado o pH. Empregou-se máquina de varredura e microscópio estereoscópico para as avaliações da população acarina. A adição de Natur'l Óleo pode afetar negativamente a eficiência do pyridaben 200 CE e 750 PM e cyhexatin 500 PM, no controle do ácaro-da-leprose. Triona e Assist não afetaram as eficiências dos acaricidas testados. Pelo índice de iodo, mediu-se o grau de insaturação das misturas dos acaricidas com Natur'l Óleo, concluindo-se que houve incorporação das moléculas dos acaricidas pelas ligações insaturadas do óleo; porém, isto não explica o diferente comportamento dos produtos no controle do ácaro da leprose dos citros.

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In order to calculate the daily stress degree of a bean crop submitted to four water regime applications, cover crop and air daily measurements temperatures were accomplished by using a hand-held infrared thermometer. The treatments did not present crop water stress except the control (without irrigation). The highest yield was obtained by the treatment that received less irrigation frequency, and among the treatments that had the same number of irrigation. The largest yield was obtained with the one that received larger amount of applied water. The largest irrigation frequency did not result in larger productivity. The methodologies used for the irrigation planning were efficient for the replacement of soil water. The daily stress degree index was effective in determining crop water stress; and it was reliable presenting negative values in good water soil condition.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Objectives: The purpose of this study was to determine if intra-abdominal pressure (IAP) could predict acute renal injury (AKI) in the postoperative period of abdominal surgeries, and which would be its cutoff value. Patients and methods: A prospective observational study was conducted in the period from January 2010 to March 2011 in the Intensive Care Units (ICUs) of the University Hospital of Botucatu Medical School, UNESP. Consecutive patients undergoing abdominal surgery were included in the study. Initial evaluation, at admission in ICU, was performed in order to obtain demographic, clinical surgical and therapeutic data. Evaluation of IAP was obtained by the intravesical method, four times per day, and renal function was evaluated during the patient's stay in the ICU until discharge, death or occurrence of AKI. Results: A total of 60 patients were evaluated, 16 patients developed intra-abdominal hypertension (IAH), 45 developed an abnormal IAP (>7 mmHg) and 26 developed AKI. The first IAP at the time of admission to the ICU was able to predict the occurrence of AKI (area under the receiver-operating characteristic curve was 0.669; p=0.029) with the best cutoff point (by Youden index method) >= 7.68 mmHg, sensitivity of 87%, specificity of 46% at this point. The serial assessment of this parameter did not added prognostic value to initial evaluation. Conclusion: IAH was frequent in patients undergoing abdominal surgeries during ICU stay, and it predicted the occurrence of AKI. Serial assessments of IAP did not provided better discriminatory power than initial evaluation.

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Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached-deodorized (RBD) soybean oil. The oxidative stability of the oil samples was determined using the Oil Stability Index method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. All extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Oil Stability Index method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT. The present study confirmed that gamma radiation did not affect the peanut skin extracts' antioxidative properties when added to soybean oil.