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Towards an Automatic Health Monitor for Autonomous Underwater Vehicles using Parameter Identification

Healey, A.J.
Fonte: Escola de Pós-Graduação Naval Publicador: Escola de Pós-Graduação Naval
Relevância na Pesquisa
16.53%
American Control Conference, 1993; In the last few years, interest has grown in the use of autonomous underwater vehicles for commercial, scientific and military missions. Reliability is critical and autonomous fault detection with programmed recovery procedures have to be built into their control logic. It is important that the mission controller have information concerning the current status of the maneuverability subsystems of the vehicle to perform requested motions. The normal techniques of servo error monitors, limit and trend checks, and Kalman filter state estimators with innovations checks go a long way to providing sensor fault detection. However, the inherent capability of a vehicle to determine the state of health of its steering, diving, and speed subsystems (including fin jams) is not easily discovered by these methods. This paper discusses the use of both batch least squares and Kalman Filters for system parameter identification as a means to detect a change in performance. Applied to the experimental maneuvering responses of the NPS AUV II autonomous underwater vehicle we wish to determine the range of varability of key steering system response parameters that would form the basis of a health monitor. In this application we are not seeking parameter values for the purpose of adaptive control. Instead...

Was malthus right? a var analysis of economic and demographic interactions in pre-industrial England

Nicolini, Esteban A.
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: Trabalho em Andamento Formato: application/pdf
Publicado em /02/2006 ENG; ENG
Relevância na Pesquisa
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This paper shows that the interaction between economic and demographic variables in England before the onset of modern economic growth did not fit some crucial assumptions of the Malthusian model. I estimated a vector autoregression for data on fertility, nuptiality, mortality and real wages over the period 1541-1840 applying a well-known identification strategy broadly used in macroeconomics. The results show that endogenous adjustment of population to real wages functioned as Malthus assumed only until the 17th century: positive checks disappeared during the 17th century and preventive checks disappeared before 1740. This implies that the endogenous adjustment of population levels to changes in real wages -one of the cornerstones of the Malthusian model- did not work during an important part of the period usually considered within the "Malthusian regime".

Genetic progress after cycles of upland rice recurrent selection

Morais Júnior,Odilon Peixoto de; Melo,Patrícia Guimarães Santos; Morais,Orlando Peixoto de; Castro,Adriano Pereira de; Breseghello,Flávio; Utumi,Marley Marico; Pereira,José Almeida; Wruck,Flávio Jesus; Colombari Filho,José Manoel
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 EN
Relevância na Pesquisa
16.53%
Periodic assessment of the genetic progress made in recurrent selection programs is essential for assessing the evolution of the programs and identifying the main factors that have contributed to this progress. This study aimed to estimate genetic progress in grain yield, plant height and days-to-flowering achieved in the CNA6 population of upland rice (Oryza sativa L.), after four cycles of recurrent selection; and evaluate the genetic potential of this population to generate superior inbred lines after each selection cycle. The experimental data were obtained from progeny yield trials of each recurrent selection cycle. These trials were carried out in two or three locations per cycle, and consisted of S0:2 progenies and at least three checks. Federer’s augmented block design, with one replication on location (the environment), was adopted. Results revealed genetic progress for grain yield and plant height, with total genetic gains of 375.87 kg ha−1 and -3.90 cm, respectively, during the four selection cycles. The annual relative gain observed for grain yield was 1.54 %. The genetic potential of the population was analysed by the expected proportion of superior inbred lines. The standard adopted as the limit for obtaining superior inbred lines was the average of the checks for each trait. The genetic potential for grain yield and plant height increased during the study period. For days-to-flowering...

Enhancements for the CAPS prototyping system description language syntax-directed editor

Grosenheider, Scott Robert
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: 269 p.
EN_US
Relevância na Pesquisa
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CAPS (Computer-Aided Prototyping System) is an integrated set of software tools that generate source programs directly from real time requirements. CAPS users can specify the requirements of prototypes as augmented computational graphs using the graphics/text editor. The problem with the current version of CAPS is that most of the feasibility checks for the prototypes are currently enforced by the translator and the scheduler. Sucb an approach requires the engineers to go through the 'edit, save file, then translate and schedule' cycle in order to find out if the control and timing constraints can be satisfied. The prototyping process can be made much more efficient and user-friendly if these checks are enforced by the CAPS PSDL (prototype System Description Language) SDE (syntax-directed editor), where users can detect and receive warnings as they enter the design. This thesis focuses on the properties that must exist between processes and their interconnected data flows in order for a prototype to be correct. It further modifies the PSDL SDE so that parts of the prototype are captured, combined, and manipulated in a way that provides the semantic information needed to determine if these properties have been violated. The new editor has been applied to several prototype examples. The results showed that...

Practical soft typing

Wright, Andrew Kevin
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Thesis; Text Formato: 158 p.; application/pdf
ENG
Relevância na Pesquisa
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Soft typing is an approach to type checking for dynamically typed languages. Like a static type checker, a soft type checker infers syntactic types for identifiers and expressions. But rather than reject programs containing untypable fragments, a soft type checker inserts explicit run-time checks to ensure safe execution. Soft typing was first introduced in an idealized form by Cartwright and Fagan. This thesis investigates the issues involved in designing a practical soft type system. A soft type system for a purely functional, call-by-value language is developed by extending the Hindley-Milner polymorphic type system with recursive types and limited forms of union types. The extension adapts Remy's encoding of record types with subtyping to union types. The encoding yields more compact types and permits more efficient type inference than Cartwright and Fagan's early technique. Correctness proofs are developed by employing a new syntactic approach to type soundness. As the type inference algorithm yields complex internal types that are difficult for programmers to understand, a more familiar language of presentation types is developed along with translations between internal and presentation types. To address realistic programming languages like Scheme...

Soft typing: An approach to type checking for dynamically typed languages

Fagan, Mike
Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Thesis; Text Formato: 174 p.; application/pdf
ENG
Relevância na Pesquisa
16.53%
In an effort to avoid improper use of program functions, modern programming languages employ some kind of preventative type system. These type systems can be classified as either static or dynamic. Static type systems detect "ill-typed" program phrases at compile-time, whereas dynamic type systems detect "ill-typed" phrases at run-time. Static typing systems have two important advantages over dynamically typed systems: First, they provide important feedback to the programmer by detecting a large class of program errors before execution. Second, they extract information that a compiler can exploit to produce more efficient code. The price paid for these advantages, however, is a loss of expressiveness and modularity. It is easy to prove that a static type system for an "interesting" programming language necessarily excludes some "good" programs. This paper focuses on the problem of designing programming systems that retain the all the expressiveness of dynamic typing, but still offer the early error detection and improved optimization opportunities of static typing. To that end, we introduce a concept called soft typing. The key concept of soft typing is that a type checker need not reject programs containing statically "ill-typed" phrases. Instead...

Authority in Search of Liberty: The prefects in liberal Italy

RANDERAAD, Nico
Fonte: Amsterdam, Thesis Publishers Publicador: Amsterdam, Thesis Publishers
Tipo: Livro
EN
Relevância na Pesquisa
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(Published version of EUI PhD thesis, 1992.); --List of tables --List of abbreviations --Preface --1 Administration between state and society in post-Napoleonic Europe 13 --1 The primacy of the state 13 --2 The organization of local administration 18 --3 Italy before Unification 22 --2 The prefects as mediators between state and society 30 --1 The historiography 30 --2 The prefects 33 --3 Administration in the field 39 --3 Control of local government: 'childish tutelage' and emancipation 45 --1 Introduction 45 --2 The appointment of mayors 50 --3 Political interference in the nomination of mayors 56 --4 Local elections 60 --5 Conclusion 71 --4 The dissolution of municipal councils: administration and politics 73 --1 Introduction 73 --2 The legal background 77 --3 The dissolution in practice 81 --4 Conclusion 96 --5 Control of municipal services: uniformity and tradition 98 --1 Introduction 98 --2 Meetings of the communal council 100 --3 Municipal services 103 --4 Prefectural checks 111 --5 Conclusion 116 --6 The checking of local finances: control and modernizing initiatives 120 --1 Introduction 120 --2 The significance of statistics on local finance 127 --3 The role of the provincial deputation 133 --4 The abortive start of the system of local finance 138 --5 The enduring crisis 149 --6 Conclusion 156 --7 Parliamentary elections between manipulation and the construction of a representative system 160 --1 Introduction 160 --2 Checks and balances in the government's electoral strategy 164 --3 The revision of the electoral rolls 170 --4 Political mobilization and control in the periphery 174 --5 Conclusion 183 --Conclusion 186 --Bibliography 193 --Appendix 206 --Index 222

Secondary pyrrhotite as a recorder of Earth Magnetic field variations; Sekundärer Pyrrhotin als Aufzeichnungsmedium für Variationen des Erdmagnetfelds

Wehland, Florian
Fonte: Universität Tübingen Publicador: Universität Tübingen
Tipo: Dissertation; info:eu-repo/semantics/doctoralThesis
EN
Relevância na Pesquisa
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Paleomagnetic recording of Earth magnetic field (EMF) variations plays an essential part in understanding the origin and behaviour of the EMF. As the common recorders like sediments or basalts are all dealing with intrinsic problems like the lock-in-depth-problem or time-gaps, the aim of this thesis is to test the potential and quality of secondary pyrrhotite in contact metamorphic, marly limestones as a new recorder of EMF variations. The advantage of this technique is to combine the rockmagnetic qualities of a TRM record with a continuous recording process. Therefore, the magnetic particle assemblages of samples from four locations (Manaslu, Nepal; Isle of Skye, Scotland; Bourg d'Oisan, France; Elba Island, Italy) were investigated in advance using microscopic (light microscopy, SEM, TEM) and rockmagnetic techniques (IRM, FORC, delta M). In addition, the recording quality (additivity and independence of pTRM) was tested by the means of laboratory pTRM checks and artificial Thellier-Thellier-Experiments. The method was successfully tested on a site from central Elba, where the NRM is a clear secondary TRM consisting of two antiparallel components and a broad transition. The derived paleofield values are similar to the present day field in Elba...

The effects of prenatal exposure to buprenorphine or methadone on infant visual evoked potentials

Whitham, J.; Spurrier, N.; Sawyer, M.; Baghurst, P.; Taplin, J.; White, J.; Gordon, A.
Fonte: Pergamon-Elsevier Science Ltd Publicador: Pergamon-Elsevier Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
16.53%
This study compared the neurological development of 4 month old infants exposed to buprenorphine or methadone during pregnancy to that of a control group of non-exposed infants. Participants were 30 buprenorphine-maintained women, 22 methadone-maintained women and 33 non opioid-dependent controls, and their infants. Women were enrolled during pregnancy as part of an open-label non-randomised flexible-dosing longitudinal study. Groups were matched for maternal age, parity, gravida, and tobacco and alcohol use. Infant neurological development was assessed by measuring latency of pattern reversal visual evoked potentials (VEP). One-way between groups analyses of variance (ANOVA) were conducted to test the statistical significance of differences between the mean latencies of the peak response to two different sized checkerboard patterns (48' and 69' of retinal arc). Infants prenatally exposed to methadone had significantly prolonged latencies, compared with infants in the control group and infants prenatally exposed to buprenorphine, in response to checks of 48' and 69'. VEP latencies of infants prenatally exposed to buprenorphine did not differ significantly from controls for either check size. After adjustment for covariates, prenatal exposure to methadone remained a significant predictor of VEP response to checks of 48'...

Software-based reference protection for component isolation.

Yarom, Yuval
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
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Reference protection mechanisms are commonly used to isolate and to provide protection for components that execute within a shared run-time environment. These mechanisms often incur an overhead due to maintaining the isolation or introduce inefficiencies in the communication between the components. Past research operated under the assumption that some performance loss is an acceptable price for the added security that comes with better isolation. This thesis sets out to demonstrate that good isolation does not imply performance loss. While numerous models for implementing reference protection have been suggested, there is a lack of a unified terminology that allows the comparison of systems from across the domain. This thesis presents a classification framework that captures the trade-offs present in the design of reference protection. It identifies four main models of reference protection: complete isolation, where components do not share references to objects; object sharing, where components can share data while still maintaining private, unshared data; partial isolation, where components have private, unshared data and an exposed interface that allows other component's indirect access to the private data; and initial isolation...

Theological reflection at work: A phenomenological study of learning processes

Gallagher, Suzanne J
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
16.53%
Using the learning descriptions of graduates of a graduate ministry program, the mechanisms of interactions between the knowledge facets in learning processes were explored and described. The intent of the study was to explore how explicit, implicit, and emancipatory knowledge facets interacted in the learning processes at or about work. The study provided empirical research on Yang's (2003) holistic learning theory. ^ A phenomenological research design was used to explore the essence of knowledge facet interactions. I achieved epoche through the disclosure of assumptions and a written self-experience to bracket biases. A criterion based, stratified sampling strategy was used to identify participants. The sample was stratified by graduation date. The sample consisted of 11 participants and was composed primarily of married (n = 9), white, non-Hispanic (n = 10), females (n = 9), who were Roman Catholic (n = 9). Professionally, the majority of the group were teachers or professors (n = 5). ^ A semi-structured interview guide with scheduled and unscheduled probes was used. Each approximately 1-hour long interview was digitally recorded and transcribed. The transcripts were coded using a priori codes from holistic learning theory and one emergent code. The coded data were analyzed by identifying patterns...

Are Pakistan's Women Entrepreneurs Being Served by the Microfinance Sector?

Safavian, Mehnaz; Haq, Aban
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
Tipo: Publications & Research :: Publication; Publications & Research
EN_US
Relevância na Pesquisa
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Fostering the entrepreneurship of women is important for Pakistan's economic growth and inclusion agenda, and access to financial services is an important component of starting and growing a business for women entrepreneurs. Most women?owned businesses are small, household?based cottage industries; microfinance products should be a natural source of start?up and working capital finance for this clientele. Microfinance portfolio data suggest that although Pakistan's sector has shown improvement in reaching women, it still lags its regional peers, only 59 percent of microfinance clients are women. The original purpose of this work was to determine whether women entrepreneurs have access to, and are using, microfinance loans as a source of finance for their businesses. However, the findings of the report go beyond the narrow objective of understanding whether microfinance institutions (MFIs) are reaching Pakistan's businesswomen. As the research unfolded, the evidence suggested that not only are women entrepreneurs not being served, but also that the outreach to women in general is potentially more limited than previously assumed and that the issues of consumer protection and responsible lending practices in Pakistan might merit further exploration. The report raises and addresses two distinct issues. First...

Political Economy Studies : Are They Actionable? Some Lessons from Zambia

Beuran, Monica; Raballand, Gaël; Kapoor, Kapil
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Publications & Research :: Policy Research Working Paper
ENGLISH
Relevância na Pesquisa
16.53%
In recent years, the number of studies looking at the effect of politics on economic outcomes has flourished. For developing economies, these studies are useful to better understand why long overdue reforms are not implemented. The studies analyze the overall context within which reforms are being implemented and the underlying incentive framework. However, it seems difficult to make such studies actionable, especially in sectors where donors have a heavy presence that can sometimes distort incentives in addition to the reluctance from some governments to amend the existing systems in place. This paper focuses on some conclusions emerging from the political economy diagnostics carried out in Zambia in various sectors in recent years. Based on interviews of World Bank task managers, the paper attempts to assess the relevance of these studies for the implementation of projects and the policy dialogue and draws lessons on how they have influenced the implementation of the World Bank's support to programs in various sectors in Zambia as well as the main challenges for this type of exercise.

Incentive Compatible Reforms : The Political Economy of Public Investments in Mongolia

Hasnain, Zahid
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Publications & Research :: Policy Research Working Paper
ENGLISH
Relevância na Pesquisa
16.53%
Why do politicians distort public investments? And given that public investments are poor because presumably that is what is politically rational, what types of reforms are likely to be both efficiency improving and compatible with the interests of politicians? This paper explores these two questions in the context of Mongolia. It argues that Mongolian members of parliament have an incentive to over-spend on smaller projects that bring benefits to specific geographical localities and to under-spend on large infrastructure that would bring economic benefits to Mongolia on the whole. The incentive for the former is that members of parliament internalize the political benefits from the provision of particular, targeted benefits to specific communities. The disincentive for the latter is that large infrastructure carries a political risk because the political faction in control of that particular ministry would have access to huge rents and become politically too powerful. The identity of these "winners" is uncertain ex ante...

Financial Liberalization and Allocative Efficiency of Capital

Kukenova, Madina
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Publications & Research :: Policy Research Working Paper
ENGLISH
Relevância na Pesquisa
16.53%
Financial liberalization may have a positive effect on growth not only through the increase in the quantity of the available funds, but also through a more efficient allocation of resources across firms and sectors. Despite this intuitive appeal, there is little empirical evidence on the positive effect of financial liberalization on capital allocation. The main difficulty of investigating the linkage between liberalization of financial markets and capital allocation efficiency lies in the fact that the efficiency of capital allocation is not directly observable. One way to address this issue is to evaluate the effect of financial liberalization within the Heckscher-Ohlin framework. Producing and exporting products inconsistent with a country's factor endowments constitutes a serious misallocation of the funds, which undermines competitiveness of the economy and inhibits its long run growth. This paper tests the allocative efficiency hypothesis by evaluating the effect of stock market liberalization on the survival of different product categories using export data for 91 countries over the period of 1975-2003. Preliminary results suggest that after liberalization of the domestic stock market...

Mongolia : The Political Economy of the Resource Paradox, Synthesis Note

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Policy Note; Economic & Sector Work
ENGLISH; EN_US
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This report discusses Mongolia's increasing dependence on mining revenues and the associated vulnerability to boom and bust economic cycles, and calls for special attention to governance in mining resource management. It seeks to identify can be learned from the experiences of other mineral dependent countries that have succeeded in converting their mineral endowment into broadly shared growth, as well as from those that have not. A challenge for the Bank is to be able to formulate good reform solutions which fit the country's' implementation capacity, and are flexible enough to respond to changing country dynamics. The Bank could modify its support better correspond to Mongolia's realities, such as taking into account concerns that by entering into an investment agreement, the government will lose the ability to influence or veto decisions that negatively impact national security. The report looks at the Public Investment Program, focusing on the principles of development oriented investments, and what this would imply across sectors...

Do Export Promotion Agencies Promote New Exporters?

Cruz, Marcio
Fonte: World Bank Group, Washington, DC Publicador: World Bank Group, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
16.53%
Do export promotion agencies impact the probability of non-exporting firms to export? In the last decade many countries have introduced export promotion agencies to support their firms to deal with asymmetric information problems and make feasible additional gains from trade. Some recent studies have found that the support of these agencies has been effective with respect to the intensive and extensive margins of trade. Nevertheless, because of the lack of information on non-exporting firms, few of them analyze their impact on the probability of promoting new exporters. This paper evaluates the impact of the Brazilian Trade and Investment Promotion Agency (Apex-Brasil) on firms' export status using a unique firm-level dataset that covers the full manufacturing sector in Brazil. To identify the impact of Apex's assistance on firms' export propensity, the paper relies on a procedure of matching difference-in-difference estimators. The empirical results show evidence of the program's positive impact on the probability of promoting new exporters. The effect is heterogeneous according to firms' size categories and sectors. Furthermore...

Spillover Effects of Exchange Rates : A Study of the Renminbi

Mattoo, Aaditya; Mishra, Prachi; Subramanian, Arvind
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Publications & Research :: Policy Research Working Paper
ENGLISH
Relevância na Pesquisa
16.53%
This paper estimates how changes in China's exchange rates would affect exports from competitor countries in third-country markets -- in other words, the "spillover effect." The authors use recent theory to develop an identification strategy, with a key role for the competition between China and its developing country competitors in specific products and export destinations. Using disaggregated trade data, they estimate the spillover effect by exploiting the variation across different exporters, importers, products, and time periods. They find a spillover effect that is statistically and quantitatively significant. Their estimates suggest that a 10-percent appreciation of China's real exchange rate boosts a developing country's exports of a typical four-digit Harmonized System product category to third markets by about 1.5 to 2 percent on average. The magnitude of the spillover effect varies systematically with the characteristics of products, such as the extent to which they are differentiated.

Tapering Talk : The Impact of Expectations of Reduced Federal Reserve Security Purchases on Emerging Markets

Eichengreen, Barry; Gupta, Poonam
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
16.53%
In May 2013, Federal Reserve officials first began to talk of the possibility of tapering their security purchases. This tapering talk had a sharp negative impact on emerging markets. Different countries, however, were affected very differently. This paper uses data on exchange rates, foreign reserves and equity prices between April and August 2013 to analyze who was hit and why. It finds that emerging markets that allowed the real exchange rate to appreciate and the current account deficit to widen during the prior period of quantitative easing saw the sharpest impact. Better fundamentals (the budget deficit, the public debt, the level of reserves, or the rate of economic growth) did not provide insulation. A more important determinant of the differential impact was the size of the country's financial market: countries with larger markets experienced more pressure on the exchange rate, foreign reserves, and equity prices. This is interpreted as showing that investors are better able to rebalance their portfolios when the target country has a relatively large and liquid financial market.

Argentina - Report on the Observance of Standards and Codes (ROSC) : Accounting and Auditing; Argentina - lnforme Sobre El Cumplimiento de Normas y Codigos (ROSC) : Contabilidad y Auditoria

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Insolvency Assessment (ROSC); Economic & Sector Work
ENGLISH
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Strengthening corporate financial reporting is important for Argentina, as the country seeks to foster confidence in the local business community in order to stimulate investments, both local and foreign. In addition, strong corporate accounting practices enable local banks and financial institutions to monitor adequately their businesses risks, credit and otherwise, which is essential at a time when the Argentine banking sector emerges from the crisis triggered by the events of December 2001. Sound accounting and auditing is therefore essential to the stability of Argentina's banking sector. This report analyzes Argentina's corporate financial reporting and auditing practices with a view to supporting the Government's strategy to: (a) improve the investment climate for Argentine companies; (b) foster trade competitiveness by aligning the standards of reporting and governance with practices that are prevalent among the country's main trading partners; and (c) ensure greater transparency in both the private and public sectors. International Financial Reporting Standards (IFRS)...