964 resultados para discriminants of number fields
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2000 Mathematics Subject Classification: 11S31 12E15 12F10 12J20.
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MSC 2010: 54A25, 54A35.
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A pénzügy kutatócsoport a TÁMOP-4.2.1.B-09/1/KMR-2010-0005 azonosítójú projektjében igen szerteágazó elemzési munkát végzett. Rámutattunk, hogy a különböző szintű gazdasági szereplők megnövekedett tőkeáttétele egyértelműen a rendszerkockázat növekedéséhez vezet, hiszen nő az egyes szereplők csődjének valószínűsége. Ha a tőkeáttételt eltérő mértékben és ütemben korlátozzák az egyes szektorokban, országokban akkor a korlátozást később bevezető szereplők egyértelműen versenyelőnyhöz jutnak. Az egyes pénzügyi intézmények tőkeallokációját vizsgálva kimutattuk, hogy a különféle divíziók közt mindig lehetséges a működés fedezetésül szolgáló tőkét (kockázatot) úgy felosztani, hogy a megállapodás felmondás egyik érintettnek se álljon érdekében. Ezt azonban nem lehet minden szempontból igazságosan megtenni, így egyes üzletágak versenyhátrányba kerülhetnek, ha a konkurens piaci szereplők az adott tevékenységet kevésbé igazságtalanul terhelték meg. Kimutattunk, hogy az egyes nyugdíjpénztárak befektetési tevékenységének eredményességére nagy hatással van a magánnyugdíjpénztárak tevékenységének szabályozása. Ezek a jogszabályok a társadalom hosszú távú versenyképességére vannak hatással. Rámutattunk arra is, hogy a gazdasági válság előtt a hazai bankok sem voltak képesek ügyfeleik kockázatviselő képességét helyesen megítélni, ráadásul jutalékrendszerük nem is tette ebben érdekelté azokat. Számos vizsgálatunk foglalkozott a magyar vállalatok versenyképességének alakulásával is. Megvizsgáltuk a különféle adónemek, árfolyamkockázatok és finanszírozási politikák versenyképességet befolyásoló hatását. Külön kutatás vizsgálta a kamatlábak ingadozásának és az hitelekhez kapcsolódó eszközfedezet meglétének vállalati értékre gyakorolt hatásait. Rámutattunk a nemfizetés növekvő kockázatára, és áttekintettük a lehetséges és a ténylegesen alkalmazott kezelési stratégiákat is. Megvizsgáltuk azt is, hogy a tőzsdei cégek tulajdonosai miként használják ki az osztalékfizetéshez kapcsolódó adóoptimalizálási lehetőségeket. Gyakorlati piaci tapasztalataik alapján az adóelkerülő kereskedést a befektetők a részvények egy jelentős részénél végrehajtják. Külön kutatás foglakozott a szellemi tőke hazai vállalatoknál játszott szerepéről. Ez alapján a cégek a problémát 2009-ben lényegesen magasabb szakértelemmel kezelték, mint öt esztendővel korábban. Rámutattunk arra is, hogy a tulajdonosi háttér lényeges hatást gyakorolhat arra, ahogyan a cégek célrendszerüket felépítik, illetve ahogy az intellektuális javakra tekintenek. _____ The Finance research team has covered a wide range of research fields while taking part at project TÁMOP-4.2.1.B-09/1/KMR-2010-0005. It has been shown that the increasing financial gearing at the different economic actors clearly leads to growth in systematic risk as the probability of bankruptcy climbs upwards. Once the leverage is limited at different levels and at different points in time for the different sectors, countries introducing the limitations later gain clearly a competitive advantage. When investigating the leverage at financial institutions we found that the capital requirement of the operation can always be divided among divisions so that none of them would be better of with cancelling the cooperation. But this cannot be always done fairly from all point of view meaning some of the divisions may face a competitive disadvantage if competitors charge their similar division less unfairly. Research has also shown that the regulation of private pension funds has vital effect on the profitability of the investment activity of the funds. These laws and regulations do not only affect the funds themselves but also the competitiveness of the whole society. We have also fund that Hungarian banks were unable to estimate correctly the risk taking ability of their clients before the economic crisis. On the top of that the bank were not even interested in that due to their commission based income model. We also carried out several research on the competitiveness of the Hungarian firms. The effect of taxes, currency rate risks, and financing policies on competitiveness has been analysed in detail. A separate research project was dedicated to the effect of the interest rate volatility and asset collaterals linked to debts on the value of the firm. The increasing risk of non-payment has been underlined and we also reviewed the adequate management strategies potentially available and used in real life. We also investigated how the shareholders of listed companies use the tax optimising possibilities linked to dividend payments. Based on our findings on the Hungarian markets the owners perform the tax evading trades in case of the most shares. A separate research has been carried out on the role played by intellectual capital. After that the Hungarian companies dealt with the problem in 2009 with far higher proficiency than five years earlier. We also pointed out that the ownership structure has a considerable influence on how firms structure their aims and view their intangible assets.
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Az amerikai történelemben a paradigmaváltások meglehetősen nagyszabású és alapvető hatásokkal jártak, míg Japánban mintha hosszú távon is a Tudományos vezetés (gyártás-orientált) paradigmájánál maradtak volna, mely aztán módosult valamennyit a többi paradigma megjelenésének hatására. A tanulmány ebből az elméleti megállapításból kiindulva vizsgálja meg mind szakirodalmi alapon, mind egy kérdőíves kutatás segítségével, a japán társadalom „reakcióidejét”: attitűdjeit a változással, az alkalmazkodással szemben. Alapfeltételezése, hogy a tartós versenyképesség fenntartásához elengedhetetlen a külső körülményekhez való folyamatos alkalmazkodás, ami időről időre a múlt gyakorlatainak megkérdőjelezését eredményezi. Rövid elemzésünk azon az előfeltevésen alapult, hogy egy vagy több, a számát és / vagy társadalmi befolyását tekintve jelentős társadalmi csoport továbbra is erősen támogatja a hagyományos japán vezetési gyakorlatot. A hipotézist sikeresen bebizonyítottuk: a hagyományos menedzsmentet szignifikánsan támogatta két olyan klaszter, melyek száma jelentősen meghaladta a panel fennmaradó részét és amelyek nagyobb fokú társadalmi befolyást is képviseltek. Megállapítottuk, hogy a régi rendszert valószínűleg azok a rangidős japán férfiak támogatják, akik állandó dolgozóként vagy vezetőként dolgoznak meglehetősen nagy vállalatoknál, hosszú távú foglalkoztatásban. Egy másik csoportot is azonosítottunk az előzővel szemben, mely fiatalabb tagokból áll, változatosabb és magasabb iskolai végzettség jellemzi. Még nem egyértelmű, hogy a második csoport tagjai életkoruk előrehaladtával betagozódnak majd a japán rendszerbe és vállalatokba, ahogy az a múltban is történt, vagy továbbra is küzdenek majd a hagyományos módszerek ellen. Mindenesetre célszerűnek látszik az eredmények alapján a kutatás továbbgondolása és magyarországi megvalósítása is, ami által a magyar gazdasági és kormányzati elit a versenyképesség szempontjából értékes információkhoz juthat, nevezetesen az elavultnak számító gyakorlatok beazonosításán és az ennek fennmaradásáért felelős csoportok leírásán keresztül. _________ In the American history, change between paradigms implied rather large-scale and deep effects, whereas the Japanese seem to keep the focus on the Scientific Management (or production-oriented) paradigm which was only party altered by the others (HR, etc.). Based on this affirmation, our study examines the reactivity of Japanese society both in a theoretical and in a practical sense. We assumed first that continuous adaptation to the external conditions is an essential element of long-term competitiveness, which implies the regular questioning of old management practices. We presumed that one or several group(s) of people is (are) still strongly supporting traditional Japanese management practices and they must be important in terms of number and/or social influence. We have found evidence for our hypothesis: two significantly supportive clusters which largely outnumbered the rest of the panel and represented a higher level of social influence as well. We stated that the old system is probably supported by senior Japanese males who work as regular (core) employees or managers in rather large companies and enjoy long-term employment. Another group was also identified as a contrast to the former one, with younger members, more diversity and a higher level of education. As they grow older, the second group may become socialized into the Japanese system as happened in the past, or continue to reject traditional methods. Based on our observations, it seems useful to broaden the focus of our research and carry out a similar study in Hungary as well. This will bring valuable information on competitiveness to the business and political elite, enabling them to identify inefficient old practices and to better target the groups responsible for maintaining those practices.
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Sustainability issues in purchasing are receiving greater attention. Literature is rapidly growing, with several research programs being initiated to investigate the topic. This study presents the results of a research project which aims to reveal and structure the motivating forces leading companies to make efforts in sustainability purchasing and the means used to attain achievements in some fields of sustainability. Results presented in the literature are scattered in terms of the fields of sustainability: most of the studies focus only on green or corporate social responsibility issues and there is a lack of exploratory models. Sustainability in purchasing is addressed in a comprehensive way including green, social responsibility and corporate growth issues. After presenting the results of a literature review, theoretical development was undertaken to create a framework in which it is possible to describe the means of sustainability applied and the motivating forces behind them. This framework serves as the basis for an empirical investigation among Hungarian companies. Empirical results confirm the usefulness of the theoretical framework: the number and the characteristics of sustainability activities were determined by the particular types of motivation – to avoid negative effects, to achieve compliance with expectations and to attain positive effects.
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The purpose of this study was to examine the effectiveness of peer counseling on high school students who have previously failed two or more classes in a nine week quarter.^ This study was constructed by comparing students who previously failed and were subsequently given peer counseling with a matched group of students who failed and did not receive peer counseling.^ To test the proposed research question, 324 students from a large urban school system were randomly chosen from a computer generated list of students who failed courses, matched on variables of number of classes failed, grade level and gender. One student from each matched pair was randomly placed in either the experimental or control group. 162 students from Group 1 (experimental) were assigned a peer counselor with their pair assigned to Group 2 (control). Group 1 received peer counseling at least 4 times during the third nine week academic quarter (Quarter 3) while Group 2 did not.^ The Grade Point Averages (GPA) for all students were collected both at the end of Quarter 2 and Quarter 3, at which time peer counseling was terminated. GPA's were also collected nine weeks after counseling was terminated.^ Results were determined by multiple regression, analysis of covariance and t-test. A level of significance was set at.05. There was significant increase in the GPA's of those counseled students immediately after peer counseling and also nine weeks after counseling was terminated, while the group not receiving peer counseling showed no increase. It was noted that there were significantly more school drop-outs from the non-counseled group than the counseled group. The number of classes failed, high school attended, grade level and gender were not found to be significant.^ The conclusion from this study was that peer counseling does impact significantly on the GPA's of students experiencing academic failure. Recommendations from this study were to implement and expand peer counseling programs with more failing students, continue counseling for longer than one quarter, include students in drop-out programs and students from different socio-economic and racial backgrounds, and conduct subsequent evaluation. ^
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The purpose of this study was to examine the relationship between Hispanic parents' sense of self-efficacy at various degrees of acculturation to the United States and specific indicators of school involvement in their elementary school children's education. It assessed the effects of acculturation on the level of parental self-efficacy and their degree of school involvement. The theoretical framework guiding this investigation was Bandura's theory of self-efficacy which advocates that the amount of effort a person devotes to the accomplishment of a specific outcome is related to a person's beliefs in their capabilities regardless of actual competencies.^ The research method involved a correlational design measuring levels of parental self-efficacy, acculturation, degree of school involvement and related demographic characteristics. Multiple regression analysis was performed to determine the degree of relationships existing between the predictor variables of self-efficacy and level of acculturation, and level of school involvement. The data was subjected to a path analysis to test the validity of the causal model advanced in this study specifying a positive relationship between the constructs of acculturation, parental self-efficacy and level of school involvement.^ A total of 109 Hispanic parents of students enrolled in five elementary public schools in Dade County, Florida, were selected for participation in the study. Results revealed a significant positive correlation r =.23, p $<$.05 between level of parental self-efficacy and number of hours parents spent helping their children with homework. A statistically significant positive correlation was found between acculturation and level of self-efficacy r =.21, p $<$.05. Statistically significant positive correlations were also found between acculturation and such indicators of parental school involvement as participation in parent-teacher conferences r =.20, p $<$.05, volunteering at school, r =.22, p $<$.05, attendance at school sponsored sports activities r =.26, p $<$.01, and volunteering in field-trips r =.28, p $<$.01.^ The multiple regression analysis equation predicting level of homework assistance provided by parents and self-efficacy was statistically significant, F(2,106) = 3.59, p $<$.03. The beta weights revealed that self-efficacy contributed the most to the prediction of homework assistance by parents, B =.258, p $<$.009. In turn, the variable of acculturation was the most significant predictor of number of school based parent involvement activities, B =.281, p $<$.05 level. The path analysis confirmed the results obtained in the multiple regression analyses, establishing self-efficacy as having a direct effect on the level of homework assistance provided by parents. Conversely, the variable of acculturation had a direct effect on the number of school based parent involvement activities. ^
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Unique electrical and mechanical properties of single-walled carbon nanotubes (SWNTs) have made them one of the most promising candidates for next-generation nanoelectronics. Efficient utilization of the exceptional properties of SWNTs requires controlling their growth direction (e.g., vertical, horizontal) and morphologies (e.g., straight, junction, coiled). ^ In this dissertation, the catalytic effect on the branching of SWNTs, Y-shaped SWNTs (Y-SWNTs), was investigated. The formation of Y-shaped branches was found to be dependent on the composition of the catalysts. Easier carbide formers have a strong tendency to attach to the sidewall of SWNTs and thus enhance the degree of branching. Y-SWNTs based field-effect transistors (FETs) were fabricated and modulated by the metallic branch of the Y-SWNTs, exhibiting ambipolar characteristics at room temperature. A subthreshold swing of 700 mV/decade and an on/off ratio of 105 with a low off-state current of 10-13 A were obtained. The transport phenomena associated with Y- and cross-junction configurations reveals that the conduction mechanism in the SWNT junctions is governed by thermionic emission at T > 100 K and by tunneling at T < 100 K. ^ Furthermore, horizontally aligned SWNTs were synthesized by the controlled modification of external fields and forces. High performance carbon nanotube FETs and logic circuit were demonstrated utilizing the aligned SWNTs. It is found that the hysteresis in CNTFETs can be eliminated by removing absorbed water molecules on the CNT/SiO2 interface by vacuum annealing, hydrophobic surface treatment, and surface passivation. SWNT “serpentines” were synthesized by utilization of the interaction between drag force from gas flow and Van der Waals force with substrates. The curvature of bent SWNTs could be tailored by adjusting the gas flow rate, and changing the gas flow direction with respect to the step-edges on a single-crystal quartz substrate. Resistivity of bent SWNTs was observed to increase with curvature, which can be attributed to local deformations and possible chirality shift at curved part. ^ Our results show the successful synthesis of SWNTs having controllable morphologies and directionality. The capability of tailoring the electrical properties of SWNTs makes it possible to build an all-nanotube device by integrating SWNTs, having different functionalities, into complex circuits. ^
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The study of transport processes in low-dimensional semiconductors requires a rigorous quantum mechanical treatment. However, a full-fledged quantum transport theory of electrons (or holes) in semiconductors of small scale, applicable in the presence of external fields of arbitrary strength, is still not available. In the literature, different approaches have been proposed, including: (a) the semiclassical Boltzmann equation, (b) perturbation theory based on Keldysh's Green functions, and (c) the Quantum Boltzmann Equation (QBE), previously derived by Van Vliet and coworkers, applicable in the realm of Kubo's Linear Response Theory (LRT). ^ In the present work, we follow the method originally proposed by Van Wet in LRT. The Hamiltonian in this approach is of the form: H = H 0(E, B) + λV, where H0 contains the externally applied fields, and λV includes many-body interactions. This Hamiltonian differs from the LRT Hamiltonian, H = H0 - AF(t) + λV, which contains the external field in the field-response part, -AF(t). For the nonlinear problem, the eigenfunctions of the system Hamiltonian, H0(E, B), include the external fields without any limitation on strength. ^ In Part A of this dissertation, both the diagonal and nondiagonal Master equations are obtained after applying projection operators to the von Neumann equation for the density operator in the interaction picture, and taking the Van Hove limit, (λ → 0, t → ∞, so that (λ2 t)n remains finite). Similarly, the many-body current operator J is obtained from the Heisenberg equation of motion. ^ In Part B, the Quantum Boltzmann Equation is obtained in the occupation-number representation for an electron gas, interacting with phonons or impurities. On the one-body level, the current operator obtained in Part A leads to the Generalized Calecki current for electric and magnetic fields of arbitrary strength. Furthermore, in this part, the LRT results for the current and conductance are recovered in the limit of small electric fields. ^ In Part C, we apply the above results to the study of both linear and nonlinear longitudinal magneto-conductance in quasi one-dimensional quantum wires (1D QW). We have thus been able to quantitatively explain the experimental results, recently published by C. Brick, et al., on these novel frontier-type devices. ^
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The study of transport processes in low-dimensional semiconductors requires a rigorous quantum mechanical treatment. However, a full-fledged quantum transport theory of electrons (or holes) in semiconductors of small scale, applicable in the presence of external fields of arbitrary strength, is still not available. In the literature, different approaches have been proposed, including: (a) the semiclassical Boltzmann equation, (b) perturbation theory based on Keldysh's Green functions, and (c) the Quantum Boltzmann Equation (QBE), previously derived by Van Vliet and coworkers, applicable in the realm of Kubo's Linear Response Theory (LRT). In the present work, we follow the method originally proposed by Van Vliet in LRT. The Hamiltonian in this approach is of the form: H = H°(E, B) + λV, where H0 contains the externally applied fields, and λV includes many-body interactions. This Hamiltonian differs from the LRT Hamiltonian, H = H° - AF(t) + λV, which contains the external field in the field-response part, -AF(t). For the nonlinear problem, the eigenfunctions of the system Hamiltonian, H°(E, B) , include the external fields without any limitation on strength. In Part A of this dissertation, both the diagonal and nondiagonal Master equations are obtained after applying projection operators to the von Neumann equation for the density operator in the interaction picture, and taking the Van Hove limit, (λ → 0 , t → ∞ , so that (λ2 t)n remains finite). Similarly, the many-body current operator J is obtained from the Heisenberg equation of motion. In Part B, the Quantum Boltzmann Equation is obtained in the occupation-number representation for an electron gas, interacting with phonons or impurities. On the one-body level, the current operator obtained in Part A leads to the Generalized Calecki current for electric and magnetic fields of arbitrary strength. Furthermore, in this part, the LRT results for the current and conductance are recovered in the limit of small electric fields. In Part C, we apply the above results to the study of both linear and nonlinear longitudinal magneto-conductance in quasi one-dimensional quantum wires (1D QW). We have thus been able to quantitatively explain the experimental results, recently published by C. Brick, et al., on these novel frontier-type devices.
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A practical approach to estimate rock thermal conductivities is to use rock models based just on the observed or expected rock mineral content. In this study, we evaluate the performances of the Krischer and Esdorn (KE), Hashin and Shtrikman (HS), classic Maxwell (CM), Maxwell-Wiener (MW), and geometric mean (GM) models in reproducing the measures of thermal conductivity of crystalline rocks.We used 1,105 samples of igneous and metamorphic rocks collected in outcroppings of the Borborema Province, Northeastern Brazil. Both thermal conductivity and petrographic modal analysis (percent volumes of quartz, K-feldspar, plagioclase, and sum of mafic minerals) were done. We divided the rocks into two groups: (a) igneous and ortho-derived (or meta-igneous) rocks and (b) metasedimentary rocks. The group of igneous and ortho-derived rocks (939 samples) covers most the lithologies de_ned in the Streckeisen diagram, with higher concentrations in the fields of granite, granodiorite, and tonalite. In the group of metasedimentary rocks (166 samples), it were sampled representative lithologies, usually of low to medium metamorphic grade. We treat the problem of reproducing the measured values of rock conductivity as an inverse problem where, besides the conductivity measurements, the volume fractions of the constituent minerals are known and the effective conductivities of the constituent minerals and model parameters are unknown. The key idea was to identify the model (and its associated estimates of effective mineral conductivities and parameters) that better reproduces the measures of rock conductivity. We evaluate the model performances by the quantity that is equal to the percentage of number of rock samples which estimated conductivities honor the measured conductivities within the tolerance of 15%. In general, for all models, the performances were quite inferior for the metasedimentary rocks (34% < < 65%) as compared with the igneous and ortho-derived rocks (51% < < 70%). For igneous and ortho-derived rocks, all model performances were very similar ( = 70%), except the GM-model that presented a poor performance (51% < < 65%); the KE and HS-models ( = 70%) were slightly superior than the CM and MW-models ( = 67%). The quartz content is the dominant factor in explaining the rock conductivity for igneous and ortho-derived rocks; in particular, using the MW-model the solution is in practice vi UFRN/CCET– Dissertação de mestrado the series association of the quartz content. On the other hand, for metasedimentary rocks, model performances were different and the performance of the KEmodel ( = 65%) was quite superior than the HS ( = 53%), CM (34% < < 42%), MW ( = 40%), and GM (35% < < 42%). The estimated effective mineral conductivities are stable for perturbations both in the rock conductivity measures and in the quartz volume fraction. The fact that the metasedimentary rocks are richer in platy-minerals explains partially the poor model performances, because both the high thermal anisotropy of biotite (one of the most common platy-mineral) and the difficulty in obtaining polished surfaces for measurement coupling when platyminerals are present. Independently of the rock type, both very low and very high values of rock conductivities are hardly explained by rock models based just on rock mineral content.
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With an increasing number of mature fields, heavy oil recovery has performed one of the great challenges of the oil industry. The Brazilian Northeast, for example, has numerous heavy oil reservoirs are explored with the use of thermal methods. Among the types of methods used for heavy oil, there is the method of in-situ combustion, a technique in which heat is produced within the container, unlike the injection of heated fluid when the heat is generated at the surface and transported to the reservoir. In this type of process, it is common to use vertical wells as injectors and producers. However, methods which use horizontal wells like oil producers are increasingly studied because of greater contact area between the formation and combustion front. Thus, the main objective of this work was to study the different configurations of wells (CIS THAITM and CAGD) in the process of in-situ combustion in oil recovery using a semi-synthetic tank with Brazilian Northeast features. The method "toe-to-heel air injection" (THAITM) is a process of enhanced oil recovery, which is the integration of in-situ combustion with technological advances in drilling horizontal wells. This method uses horizontal wells such as oil producers, keeping vertical injection wells for injecting air. The oil drain process by differential gravitational assisted with combustion (CAGD) is an integrated, in this configuration the horizontal injector well is drilled at the top formation with a horizontal production well in the lower section. The simulations were performed in a commercial program of thermal processes, called "STARS" (Steam, Thermal, and Advanced Processes Reservoir Simulator), the company CMG (Computer Modelling Group). An analysis of the air flow injection was performed and it was found that each method had a maximum injection to the base model, a show that through this air injection limit was reduced cumulative production of oil. Analyses of operating parameters were used: injection flow, configuration and completion of wells. In the sensitivity analysis we found that the air injection flow showed greater influence on THAI method, since the CIS method the completion of the wells was the most influential parameter and CAGD configuration wells showed the greatest influence in the recovered fraction. The economic results have shown that the best case obtained in CAGD method because, despite having higher initial cost showed the best financial return compared to the best cases the CIS and THAI.
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With an increasing number of mature fields, heavy oil recovery has performed one of the great challenges of the oil industry. The Brazilian Northeast, for example, has numerous heavy oil reservoirs are explored with the use of thermal methods. Among the types of methods used for heavy oil, there is the method of in-situ combustion, a technique in which heat is produced within the container, unlike the injection of heated fluid when the heat is generated at the surface and transported to the reservoir. In this type of process, it is common to use vertical wells as injectors and producers. However, methods which use horizontal wells like oil producers are increasingly studied because of greater contact area between the formation and combustion front. Thus, the main objective of this work was to study the different configurations of wells (CIS THAITM and CAGD) in the process of in-situ combustion in oil recovery using a semi-synthetic tank with Brazilian Northeast features. The method "toe-to-heel air injection" (THAITM) is a process of enhanced oil recovery, which is the integration of in-situ combustion with technological advances in drilling horizontal wells. This method uses horizontal wells such as oil producers, keeping vertical injection wells for injecting air. The oil drain process by differential gravitational assisted with combustion (CAGD) is an integrated, in this configuration the horizontal injector well is drilled at the top formation with a horizontal production well in the lower section. The simulations were performed in a commercial program of thermal processes, called "STARS" (Steam, Thermal, and Advanced Processes Reservoir Simulator), the company CMG (Computer Modelling Group). An analysis of the air flow injection was performed and it was found that each method had a maximum injection to the base model, a show that through this air injection limit was reduced cumulative production of oil. Analyses of operating parameters were used: injection flow, configuration and completion of wells. In the sensitivity analysis we found that the air injection flow showed greater influence on THAI method, since the CIS method the completion of the wells was the most influential parameter and CAGD configuration wells showed the greatest influence in the recovered fraction. The economic results have shown that the best case obtained in CAGD method because, despite having higher initial cost showed the best financial return compared to the best cases the CIS and THAI.
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The electronic journals correspond publishing channels and dissemination of scientific information. Through them, users can spread their studies as well as developing new researches. One of the systems used for creation and e-journals management is the Electronic System for Journal Publishing (SEER), used in the construction of periodic portals, as well as the creation of magazines in isolation. In this purport, it is believed that the management systems and creation of e-journals should be developed (internally and externally) according to the needs of its users. In the case of internal development, some of these processes refer to the copyright registration and submission of articles, which, in turn, are relevant tasks in the editorial process. Thus, the proposed study, thematic Usability of scientific journals, aims to analyze the usability of the copyright registration process and submission of articles in the Electronic System for Journal Publishing through BiblioCanto magazine, part of the Electronic Journals Portal of the Federal University of Rio Grande do Norte (UFRN). For the realization of the research, two valuation techniques were used: the Usability Test with a total of twenty participants and the Cooperative Evaluation, with the same number of participants separated in four categories considered target audience of that magazine, namely: undergraduate students, graduate students, teachers and librarians. The results indicated that the two analyzed processes (copyright registration and submission of articles) need improvement. In the case of the registration process, the following needs are: signalizing of the conducting registration ambient; description and exclusion of requested information on the registration form. In the process of article submission, it is emphasized improvement of aspects: the early steps to submission, signaling of required fields, concise description of the steps, minimization and review of the steps. To this end, it is believed that in general idea the SEER partially meets the needs of its users regarding the usability of such software.
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The electronic journals correspond publishing channels and dissemination of scientific information. Through them, users can spread their studies as well as developing new researches. One of the systems used for creation and e-journals management is the Electronic System for Journal Publishing (SEER), used in the construction of periodic portals, as well as the creation of magazines in isolation. In this purport, it is believed that the management systems and creation of e-journals should be developed (internally and externally) according to the needs of its users. In the case of internal development, some of these processes refer to the copyright registration and submission of articles, which, in turn, are relevant tasks in the editorial process. Thus, the proposed study, thematic Usability of scientific journals, aims to analyze the usability of the copyright registration process and submission of articles in the Electronic System for Journal Publishing through BiblioCanto magazine, part of the Electronic Journals Portal of the Federal University of Rio Grande do Norte (UFRN). For the realization of the research, two valuation techniques were used: the Usability Test with a total of twenty participants and the Cooperative Evaluation, with the same number of participants separated in four categories considered target audience of that magazine, namely: undergraduate students, graduate students, teachers and librarians. The results indicated that the two analyzed processes (copyright registration and submission of articles) need improvement. In the case of the registration process, the following needs are: signalizing of the conducting registration ambient; description and exclusion of requested information on the registration form. In the process of article submission, it is emphasized improvement of aspects: the early steps to submission, signaling of required fields, concise description of the steps, minimization and review of the steps. To this end, it is believed that in general idea the SEER partially meets the needs of its users regarding the usability of such software.