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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

此在的時間性與存有的超越界域──對《存有與時間》的一個探究

陳昀鍾 Unknown Date (has links)
本論文作為對《存有與時間》的一個探究,其研究焦點主要是針對《存有與時間》第一部的寫作計畫──藉由時間性詮釋此在,解說時間之為存有問題的超越界域──探究為何任何一種存有理解皆必須以時間為其可能界域?我首先闡釋了存有理解的可能性條件──此在的時間性,而其所綻出的超越界域,乃是存有的時間狀態,此在理解投設存有之所在。不過,在海德格的前期思路中,尚未超出界域思維,徹底達致存有自身,對於這部分我將從後期思維加以補充說明。
292

讀者理解與文本結構之交流過程──以閱讀金庸武俠小說之「美感體驗」為例 / Readers' aesthetic experience in reading Jing Yong's swordplay fictions: A reception-theory approach

賴玉釵, Lai, Yu-Chai Unknown Date (has links)
本文考察「美感體驗」意涵及發展脈絡,從審美哲學取經並依「接收美學」典範為思辨對象。該典範先賢Jauss等人認為「美感體驗」乃是「審美視域」與「文本結構」交流之產物,故「美感傳播」涉及「審美視域」、「文本結構」、「交流層次」與「美感體驗」等四者。慮及Jauss及其業師Gadamer盼望從華人文化角度了解詮釋過程又如何涵育出特定「美感體驗」,本研究訪談了16位文史科班出身之華人讀者,並選取武俠類型為讀本以理解賞析歷程。 研究發現如下: 就「審美視域」言之,華人讀者審美期待受效果歷史之約制,亦受「使用媒體經驗」、「五感聯想」、「生命週期」與「閱讀史」引導。 就讀者與文本交流之層次言之,華人讀者之創造、渲洩與否定等交流方式多少受在地文化影響。以「渲洩」為例,華人讀者可基於儒家文化或崇尚集群價值觀而「認同」角色,或因期待「皆大歡喜」結局故難接納悲劇而影響「淨化」之交流歷程,再若民族情感與集體記憶等亦扮演關鍵角色。 就「美感體驗」意涵言之,「美感」之本質實與特定社群相關,為當時語境與歷史脈絡所化育之產物。另「美感」之剖析角度亦與在地文化相繫,如華人讀者可從儒、釋、道等基底論及「美」具無常等成份,異於基督教文明強調「沐浴神恩」之感。就「美感」之功用言之,相異社群之讀者亦持不同觀點,如儒家文化涵育下讀者肯定美與「維繫倫常」及「提昇個人修為」相繫,基督教文明陶養之讀者則認為美具「社會整合」或「救贖」之效。 總體言之,本研究以華人讀者之審美歷程為省思起點,從在地角度探索接收美學可再發展之理論、研究方法與實務意涵。本研究認為,閱聽人之情感、生命階段與閱讀史均在審美歷程扮演要角,此為先前接收美學典範較少著墨之處。
293

Space Tracking Systems/ Options Study

Grelck, John, Ehrsam, Eldon, Means, James A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / This paper presents the findings of the Space Tracking Systems/Options Study (STS/OS) and indicates its impact on the telemetering community. The STS/OS was commissioned by Air Force Test & Evaluation (AF/TE) to develop a long range plan (vision and roadmap) for the AF Test & Evaluation (T&E) community to ensure affordable capabilities (telemetry, tracking and commanding) for the future (2003-2008). The study was conducted by the Air Force Materiel Command (AFMC), Space & Missile Systems Center (SMC), Detachment 9, at Vandenberg AFB (VAFB), with support from the primary AFMC T&E centers, the Air Force Operational Test & Evaluation Command (AFOTEC), and the Air Force Space Command (AFSPC). Both "open air" aeronautical and astronautical test needs were considered. The study solicited requirements for existing and future programs, extrapolated existing and planned test capabilities out into the future, then compared the two to identify future shortfalls in capabilities and specific actions that are necessary to insure that the future program needs can be met. Three critical types of testing were identified that cannot be satisfied with existing or planned instrumentation. These are: large area testing (LAT), over the horizon testing (OTH), and space weapons testing (SWT). A major deficiency was also uncovered in end game scoring for air and space intercepts, where inadequate capability exists to perform the required vector miss-distance measurement. This paper is important to the telemetering community because it identifies the Global Positioning System (GPS) as the primary time space position information (TSPI) system for all future open air testing. GPS provides a passive capability that permits each vehicle to determine its own precise TSPI. Means must be provided, however, for the vehicle to relay its position to the appropriate range control center. The paper shows that the problems with down linking telemetry, aircraft buss data, digital audio, digital video, and TSPI collectively represent the need for a very capable datalink. Likewise, the need to uplink commands, synthetic targets, synthetic backgrounds, and target control information also represents the need for a very capable datalink. With its extensive expertise in RF linkages, the telemetering community is ideally suited to address this need for a robust datalink for the future of T&E.
294

Structure-Exploiting Numerical Algorithms for Optimal Control

Nielsen, Isak January 2017 (has links)
Numerical algorithms for efficiently solving optimal control problems are important for commonly used advanced control strategies, such as model predictive control (MPC), but can also be useful for advanced estimation techniques, such as moving horizon estimation (MHE). In MPC, the control input is computed by solving a constrained finite-time optimal control (CFTOC) problem on-line, and in MHE the estimated states are obtained by solving an optimization problem that often can be formulated as a CFTOC problem. Common types of optimization methods for solving CFTOC problems are interior-point (IP) methods, sequential quadratic programming (SQP) methods and active-set (AS) methods. In these types of methods, the main computational effort is often the computation of the second-order search directions. This boils down to solving a sequence of systems of equations that correspond to unconstrained finite-time optimal control (UFTOC) problems. Hence, high-performing second-order methods for CFTOC problems rely on efficient numerical algorithms for solving UFTOC problems. Developing such algorithms is one of the main focuses in this thesis. When the solution to a CFTOC problem is computed using an AS type method, the aforementioned system of equations is only changed by a low-rank modification between two AS iterations. In this thesis, it is shown how to exploit these structured modifications while still exploiting structure in the UFTOC problem using the Riccati recursion. Furthermore, direct (non-iterative) parallel algorithms for computing the search directions in IP, SQP and AS methods are proposed in the thesis. These algorithms exploit, and retain, the sparse structure of the UFTOC problem such that no dense system of equations needs to be solved serially as in many other algorithms. The proposed algorithms can be applied recursively to obtain logarithmic computational complexity growth in the prediction horizon length. For the case with linear MPC problems, an alternative approach to solving the CFTOC problem on-line is to use multiparametric quadratic programming (mp-QP), where the corresponding CFTOC problem can be solved explicitly off-line. This is referred to as explicit MPC. One of the main limitations with mp-QP is the amount of memory that is required to store the parametric solution. In this thesis, an algorithm for decreasing the required amount of memory is proposed. The aim is to make mp-QP and explicit MPC more useful in practical applications, such as embedded systems with limited memory resources. The proposed algorithm exploits the structure from the QP problem in the parametric solution in order to reduce the memory footprint of general mp-QP solutions, and in particular, of explicit MPC solutions. The algorithm can be used directly in mp-QP solvers, or as a post-processing step to an existing solution. / Numeriska algoritmer för att effektivt lösa optimala styrningsproblem är en viktig komponent i avancerade regler- och estimeringsstrategier som exempelvis modellprediktiv reglering (eng. model predictive control (MPC)) och glidande horisont estimering (eng. moving horizon estimation (MHE)). MPC är en reglerstrategi som kan användas för att styra system med flera styrsignaler och/eller utsignaler samt ta hänsyn till exempelvis begränsningar i styrdon. Den grundläggande principen för MPC och MHE är att styrsignalen och de estimerade variablerna kan beräknas genom att lösa ett optimalt styrningsproblem. Detta optimeringsproblem måste lösas inom en kort tidsram varje gång som en styrsignal ska beräknas eller som variabler ska estimeras, och således är det viktigt att det finns effektiva algoritmer för att lösa denna typ av problem. Två vanliga sådana är inrepunkts-metoder (eng. interior-point (IP)) och aktivmängd-metoder (eng. active-set (AS)), där optimeringsproblemet löses genom att lösa ett antal enklare delproblem. Ett av huvudfokusen i denna avhandling är att beräkna lösningen till dessa delproblem på ett tidseffektivt sätt genom att utnyttja strukturen i delproblemen. Lösningen till ett delproblem beräknas genom att lösa ett linjärt ekvationssystem. Detta ekvationssystem kan man exempelvis lösa med generella metoder eller med så kallade Riccatirekursioner som utnyttjar strukturen i problemet. När man använder en AS-metod för att lösa MPC-problemet så görs endast små strukturerade ändringar av ekvationssystemet mellan varje delproblem, vilket inte har utnyttjats tidigare tillsammans med Riccatirekursionen. I denna avhandling presenteras ett sätt att utnyttja detta genom att bara göra små förändringar av Riccatirekursionen för att minska beräkningstiden för att lösa delproblemet. Idag har behovet av  parallella algoritmer för att lösa MPC och MHE problem ökat. Att algoritmerna är parallella innebär att beräkningar kan ske på olika delar av problemet samtidigt med syftet att minska den totala verkliga beräkningstiden för att lösa optimeringsproblemet. I denna avhandling presenteras parallella algoritmer som kan användas i både IP- och AS-metoder. Algoritmerna beräknar lösningen till delproblemen parallellt med ett förutbestämt antal steg, till skillnad från många andra parallella algoritmer där ett okänt (ofta stort) antal steg krävs. De parallella algoritmerna utnyttjar problemstrukturen för att lösa delproblemen effektivt, och en av dem har utvärderats på parallell hårdvara. Linjära MPC problem kan också lösas genom att utnyttja teori från multiparametrisk kvadratisk programmering (eng. multiparametric quadratic programming (mp-QP)) där den optimala lösningen beräknas i förhand och lagras i en tabell, vilket benämns explicit MPC. I detta fall behöver inte MPC problemet lösas varje gång en styrsignal beräknas, utan istället kan den förberäknade optimala styrsignalen slås upp. En nackdel med mp-QP är att det krävs mycket plats i minnet för att spara lösningen. I denna avhandling presenteras en strukturutnyttjande algoritm som kan minska behovet av minne för att spara lösningen, vilket kan öka det praktiska användningsområdet för mp-QP och explicit MPC.
295

The Vertical and Horizontal Distribution of Deep-Sea Crustaceans of the Order Euphausiacea (Malacostraca: Eucarida) from the northern Gulf of Mexico with notes on reproductive seasonality.

Fine, Charles Douglas 05 December 2016 (has links)
The vertical and horizontal distributions of Euphausiacea in the northern Gulf of Mexico, including the location of the Deepwater Horizon oil spill, were analyzed from 340 trawl samples collected between April-June, 2011. This study is the first comprehensive survey of euphausiid distributions from depths deeper than 1000 m in the Gulf of Mexico and included stratified sampling from five discrete depth ranges (0-200 m, 200-600 m, 600-1000 m, 1000-1200 m, and 1200-1500 m). In addition, this study encompasses the region heavily impacted by the Deepwater Horizon oil spill. Data presented here could potentially be used in ecosystem models investigating trophic effects of the spill because euphausiids are the preferred prey of a variety of higher trophic organisms. Lastly, these data represent the first quantification of euphausiid assemblages in this location after the Deepwater Horizon event and can serve as a basis of comparison against which to monitor recovery of the euphausiid assemblage after exposure to Deepwater Horizon hydrocarbons and dispersant in the water column.
296

Like Alike

Zevenbergen, Jill 01 January 2009 (has links)
Like Alike explores notions of pleasure and beauty through an examination of mundane activity. Pleasure is simple, uncomplicated niceness. Pleasure is forgettable and related to the norm. Beauty is complicated and hardly predicted. Finding beauty in the banal provides an escape from mundane life. The banal, then becomes unforgettable. The nondescript, everyday experience becomes important and gains meaning. Like Alike's electronic format is adapted from the original format of an artist book.
297

Horizont očekávání českých a frankofonních čtenářů knih pro děti a mládež / Horizon of expectations of Czech and French speaking readers of children's literature

Detaille Nováková, Jana January 2014 (has links)
anglicky: Title of the thesis: Horizon of expectations of Czech and French speaking readers of children's literature Keywords: czech and french children's literature, horizon of expectations, reception of literature, reader, writer's strategy, Petr Nikl, Philippe Lechermeier Abstract: The study entitled Horizon of expectations of Czech and French speaking readers of children's literature is concerned with the reception of children's literature in Czech and French speaking environment. The aim of the thesis is to find out if and how the expectations of the readers change with their literary context and to discover the extent to which the contemporary writers Petr Nikl and Philippe Lechermeier come to meet their audiences. To answer this question various methodological procedures are employed: observation and then comparison of Czech and French literary context to form the hypotheses. The hypotheses are verified by the case study based on the analyses of two books (Záhádky by Petr Nikl and Le Journal secret de Petit Poucet form Philippe Lechermeier) and on the analyses of critical reviews and comments. We discovered the writer's strategies and the expectations of the readers and we compared them with our hypotheses to make a final appraisal. The thesis is divided into eight parts: Introduction, 1....
298

[en] EVALUATION OF A SHORT PATH ALGORITHM FOR SEISMIC HORIZON TRACKING / [pt] UM ALGORITMO DE MENOR CAMINHO EM RASTREAMENTO DE HORIZONTES SÍSMICOS

ELIANA LEITE GOLDNER 18 March 2015 (has links)
[pt] A interpretação manual de um horizonte sísmico é um processo muito custoso em termos de tempo de trabalho do intérprete, o que incentiva a pesquisa de métodos automáticos, ou semi automáticos, de rastreamento. Dentre as propostas existentes baseadas em correlação, uma limitação conhecida é o uso de abordagens locais para definir as amostras pertencentes ao horizonte rastreado. Esse tipo de abordagem possui bom desempenho em dados onde não há a presença de falhas sísmicas, porém, nas regiões de baixa coerência, característica das regiões ruidosas ou de falhas, ao tomar uma decisão local o rastreador fica suscetível à propagação de erro. O objetivo deste trabalho é avaliar o uso de algoritmos de menor caminho em grafos para a solução do problema de rastreamento de horizontes sísmicos, afim de propor um método de caráter global que seja robusto a diferentes feições sísmicas. / [en] The manual interpretation of a seismic horizon is a time consuming process, which drives the research for automatic or semi automatic tracking methods. Among the known propositions that use correlation, there is a common limitation: the usage of local approaches to determine which samples belong to the horizon. This kind of approach performs well in data where there are no seismi faults. However, by using only local information, it is prone to error propagation in low coherency areas, which usualy corresponds to fault regions. The goal of this work is to evaluate the performance of shortest path algorithms as a solution for the horizont tracking problem. It intends to propose a global method that is robust to different seismic features.
299

Qualidade física de solos com horizonte antrópico (Terra Preta de Índio) na Amazônia Central / Soil physical quality of anthropics horizons (Amazonian Dark Earth) in Central Amazon

Neves Junior, Afrânio Ferreira 06 June 2008 (has links)
As Terras Pretas de Índio (TPI) apresentam por definição o horizonte A antrópico, de cor escura, com presença de artefatos líticos e/ou cerâmicos oriundos do processo de ocupação humana na Amazônia. As áreas que ocorrem se diferenciam dos solos adjacentes por exibirem e manterem condições químicas do solo adequadas ao crescimento de plantas, mesmo após vários anos de cultivo. Essa pesquisa testa a hipótese que de que as TPI exibem condições físicas do solo adequadas ao crescimento de plantas e, mais adequadas que às encontradas nos solos adjacentes. O objetivo deste estudo foi avaliar as propriedades físicas dos horizontes antrópicos de duas TPI relacionando-as com as propriedades estruturais do solo que podem limitar o crescimento de plantas. Para a realização deste estudo foram amostradas duas áreas com horizonte A antrópico (TPI) e amostras do solo adjacente. A primeira área está localizada na estação experimental da Embrapa Amazônia Ocidental (Campo Experimental do Caldeirão) no município de Iranduba, Estado do Amazonas. O solo adjacente foi classificado como Argissolo Amarelo Tb Distrófico. A segunda área está localizada em uma pequena propriedade agrícola no município de Manacapuru, Estado do Amazonas. O solo adjacente foi classificado como Latossolo Amarelo Tb Distrófico. Para a caracterização das propriedades físicas do solo, coletaram-se 120 amostras de solo indeformadas na profundidade entre 0-0,05 m e oito amostras de solo com o formato de blocos (7,0 x 15 x 22 cm). As amostras coletadas foram utilizadas para determinar a curva de retenção da água no solo, a condutividade hidráulica saturada, a curva de resistência do solo à penetração, a densidade do solo, densidade de partículas, a porosidade total do solo, a estabilidade e a resistência tênsil de agregados e a friabilidade do solo. Além das propriedades físicas, o Intervalo Hídrico Ótimo (IHO) e o índice \"S\" foram utilizados como indicadores da qualidade física do solo. A hipótese da pesquisa foi parcialmente comprovada. Os índices de qualidade do solo constataram que as Terras Pretas de Índio apresentam condições físicas do solo adequadas ao crescimento de plantas, entretanto, as TPI não apresentam propriedades físicas mais adequadas ao crescimento de plantas que os horizontes superficiais adjacentes. / Amazonian Dark Earth (ADE) presents an Anthropic A horizon, with dark color and presence of lithic and ceramics sherds. Those topsoil characteristics resulted from old Indian settlements from the pre-Columbian time in the Amazon Basin. ADE shows differences from the surrounding soils by its very good soil chemical characteristics and that are still in the most sites very fertile and productive after long time of cultivation. In this study we tested the hypothesis that ADE presents good soil physical conditions to plant growth, and more appropriate than the surrounding soil. The objective of this study was to evaluate physical properties of Anthropic horizons of two sites with ADE. The soil physical properties were discussed concerning the potencial impacts on plant growth. The Anthropic horizons from two ADE sites were sampled and also the A horizon from the surrounding soil. The ADE sites sampled were located in the Amazonas State in Brazil, one at the Experimental Research Station of Embrapa Amazônia Ocidental (Campo Experimental do Caldeirão) - Iranduba, the surrounding soil was an Dystric Yellow Acrisol. The another site was located near the city of Manacapuru - AM in a private farm. The adjacent soil in this area was classified as Dystric Yellow Ferralsol. At the depth of 0-0,05 m, 120 soil cores were collected along with eight soil box (7,0 x 15 x 22 cm). At the laboratory, soil samples were analyzed to determine: soil water retention curve, saturated hydraulic conductivity, penetration resistance curve, bulk density, particle density, total porosity, aggregate stability, tensile strength and friability. The Least Limiting Water Range (LLWR) and S indexes were used as soil physical quality indicators. The hypothesis was partially proven. The soil quality indexes indicated that ADE presented appropriate soil physical conditions for plant growth; however, the ADE had no better soil physical quality than the surrounding soil.
300

Matéria orgânica de Latossolos com horizonte A húmico / Organic matter of the Ferralsols wiht umbric epipedon

Marques, Flávio Adriano 02 February 2010 (has links)
Latossolos com horizonte A húmico (LH) são solos com importantes reservas de carbono orgânico (CO) em profundidade. Esses solos são comuns nas regiões Sudeste e Sul do Brasil, com menor ocorrência no Nordeste. Aspectos da gênese e preservação da matéria orgânica (MO) desses solos não foram completamente entendidos ainda. Particularmente interessantes são os processos responsáveis pelo espessamento (hiperdesenvolvimento) e estabilidade do CO do horizonte húmico. A hipótese de que a MO do horizonte húmico tenha importante contribuição de carbono (C) de origem pirogênica é testada. O objetivo deste trabalho foi, portanto, caracterizar quimicamente a MO do horizonte húmico e relacionar os resultados com a gênese e preservação do CO. Oito pedons de diferentes localidades do país (São Paulo, Rio de Janeiro, Minas Gerais, Paraná, Santa Catarina e Pernambuco) sob vegetação nativa foram empregados no estudo. Descrições morfológicas e análises de caracterização de rotina dos solos foram realizadas. Além disso, ácidos húmicos (AH) foram extraídos do horizonte húmico e analisados por ressonância magnética nuclear de 13C, enquanto que as frações leves (livre e oclusa), huminas e extratos alcalinos da MO dos mesmos pedons foram analisados através da pirólise. Os pedons possuem feições morfológicas conspícuas, como horizonte A hiperdesenvolvido, variando de 120 cm a 220 cm de espessura, e cores escuras em profundidade. Os horizontes húmicos são argilosos a muitos argilosos, fortemente ácidos e álicos. As formas de CO oxidável com dicromato respondem por 2/3 da reserva de carbono total (CT) do solo. Caulinita foi o principal mineral identificado por difratometria de raios X na fração argila desses indivíduos, seguido por gibbsita e, em alguns pedons, vermiculita com hidroxientrecamadas. Correlações entre atributos do solo e diferentes formas de C oxidável revelaram-se significativas apenas para alumínio pobremente cristalino extraído com oxalato de amônio ácido (r2 = 0,69), que se apresenta como um dos mecanismos de estabilização do C. Os AH apresentam estrutura química distinta entre os pedons e também variam com a profundidade, indicando, sobretudo o efeito do tipo de vegetação. Nos pedons estudados há maior concentração relativa de C alquila em superfície e C O-alquilas e C aromático em subsuperfície. A abundância de C O-alquilas sugere que boa parte da MO do horizonte húmico tem um grau de humificação pouco avançado. Os principais produtos da pirólise das frações leves, extratos alcalinos e huminas são carboidratos, compostos alifáticos e aromáticos, mas em proporções diferentes. As amostras da fração leve livre são mais ricas em resíduos frescos derivados de plantas, com presença de ligninas, enquanto que na fração leve oclusa (FLO) preponderam compostos aromáticos e alifáticos. Os extratos são enriquecidos em compostos de nitrogênio e carboidratos. A hipótese de uma MO altamente recalcitrante, formada predominantemente por produtos da decomposição de carvão foi rejeitada, já que produtos similares a esses foram encontrados apenas na FLO, que tem pouca importância no conteúdo de CT do solo. A estabilização da MO desses LH depende de 14 uma combinação de abundante entrada de biomassa e da atuação de mecanismos que retardam a mineralização da MO, como associações organominerais. / Ferralsols with umbric epipedons are soils with important organic carbon (OC) reserves in depth. These soils are common in the Southeast and South regions of Brazil, with fewer occurrences in the Northeast region. Both genesis and organic matter (OM) accumulation aspects of these soils were not completely understood yet. Particularly interesting are the soil processes responsible for thickening (over development) and for OC stability of the umbric horizon. The hypothesis that the OM from umbric epipedon has important pyrogenic carbon (C) contribution is tested. The aim of this work, therefore, was to characterize the chemistry of OM from umbric epipedon and to relate the results with soil genesis and OC preservation. Eigth pedons from different states of Brazil (São Paulo, Rio de Janeiro, Minas Gerais, Paraná, Santa Catarina and Pernambuco) under native vegetation were used in the study. Morphological descriptions and routine soil characterization analysis were carried out. Furthermore, humic acids (HA) were extracted from umbric horizon and analyzed by solid state 13C nuclear magnetic resonance, whereas light fractions (free and occluded), humin and alkaline extracts of the OM of the same pedons were analyzed by pyrolysis. The pedons have conspicuous morphological features, such as a developed umbric epipedon, ranging from 120 cm to 220 cm of thickness, and dark colors in depth. The umbric horizons are clayey to heavy clayey, strongly acidic and alic. Dichromate oxidable OC contents account for 2/3 of the total carbon (TC) soil reserve. Kaolinite is the main mineral identified by X ray diffractometry in the clay fraction, followed by gibbsite and vermiculite. Correlations between soil attributes and different forms of oxidable C were significant only for poorly crystalline aluminum forms extracted with oxalate ammonium acid (r2 = 0,69), which could be one of the C stabilization mechanisms. HA shown distinct chemical structures between pedons and also in depth, indicating the effect of the vegetation type. In the studied pedons there are higher relative concentration of alkyl C in surface and O-alkyl C and aromatic C in subsurface. Light fractions, alkaline extracts and humins main pyrolysis products are carbohydrates, aliphatic, and aromatic compounds, but in different proportions. In free light fraction (FLF) fresh residues derived from plants are common, with presence of lignin, whereas in the occluded light fraction (OLF), aromatic and aliphatic compounds predominate. Extracts are enriched in carbohydrates and N compounds. The hypothesis of a highly recalcitrant MO, produced by the fragments of charcoal in partial decomposition has been rejected, since they were found only into OLF, which has little importance in the TC content of soil. The stabilization of organic matter in these Ferralsols depends on a combination of abundant biomass input and the action of mechanisms to retard the mineralization of OM, such as a strong association with clay minerals.

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