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Author(s):  
Maria José Da Silva Feitosa ◽  
Hironobu Sano

O presente estudo tem como problema de pesquisa: De que maneira a sociologia política da ação pública contribui para esclarecer as barreiras e indutores na implementação da inovação social? Para responder tal problema, esta pesquisa propõe a utilização do pentágono de políticas públicas como modelo de análise na implementação da inovação social, tendo em vista a capacidade do mesmo para análise de aspectos cognitivos dos atores, que podem contribuir para explanar a dimensão política da inovação social, a qual é tida como incógnita que demanda esclarecimento. O estudo da implementação da inovação social a partir de um modelo de análise de implementação de políticas públicas é possível porque tanto a inovação social quanto a ação pública levam em conta os quadros cognitivos decorrentes da interação e articulação de atores, aspectos subjetivos e objetivos, com foco na solução de uma questão social como a desigualdade social, a pobreza, o crime, o analfabetismo. Tanto a ação pública quanto a inovação social consideram importante a diversidade de atores e a atuação ativa destes, o empoderamento, o protagonismo dos mesmos, na busca por soluções para questões sociais. O estudo da inovação social é relevante para toda sociedade, pois é um tema que aborda questões de interesse coletivo. O presente trabalho inova na medida em que propõe que a implementação da inovação social seja analisada por meio do pentágono de políticas públicas. Palavras-Chave: Pentágono de Políticas Públicas. Inovação Social. Barreiras. Indutores. Implementação.   Abstract: The present study has the following research problem: How does the political sociology of public action contribute to clarify the barriers and dravers in the implementation of social innovation? To answer this problem, this research proposes the use of the public policies pentagon as a model of analysis in the social innovation implementation, given its ability to analyze cognitive aspects of actors, which contribute to explain the political dimension of social innovation, which is considered a unknown variable that requires clarification. The study of social innovation implementation from a model of public policy implementation analysis is possible because both social innovation and public action take into account cognitive aspects arising from the interaction and articulation of actors, subjective and objective aspects, focused on solving a social issue such as social inequality, poverty, crime, illiteracy. Both public action and social innovation consider important the diversity of actors and their active role, their empowerment, their protagonism, in the search for solutions to social issues. The social innovation study is relevant to society as a whole, as it is a topic that addresses issues of collective interest. The present study innovates in that it proposes that the implementation of social innovation be analyzed through of the public policies pentagon. Keywords: Public Policies Pentagon. Social Innovation. Barriers.  Drivers. Implementation.  


Author(s):  
Darina G. Yordanova ◽  
Timothy J. Patterson ◽  
Colin M. North ◽  
Louise Camenzuli ◽  
Atanas S. Chapkanov ◽  
...  

2021 ◽  
Author(s):  
P. J. Singh

The classical Material Balance (P/Z) plot requires fully shut-in built-up reservoir pressure (Pr) for its calculation by generating static Pr as a function of cumulative gas production (Gp). Shut-in the well only for Pr data acquisition is impractical and creates several issues such as risk of production loss and production disturbance. Mattar & McNeil (1997) introduced Flowing Material Balance approach for gas deliverability monitoring and reserves estimation based on surface well flowing parameter by creating parallel line through the initial Pr to estimate Initial-Gas-In-Place (IGIP). The method is practical for qualitative purpose, but any dynamic behavior of the well will be challenging. Improved model is presented, a Coupled Material Balance - Nodal Analysis approach for gas deliverability monitoring and reserves quantification of connected gas in place volume (CGIP). Initial Pr as a known variable then extended by the decline of Pr as a function of Gp and improved by performing “flowing mode” Nodal Analysis, converting bottom hole flowing pressure from wellhead flowing pressure to determine estimated Pr. Pr uncertainty and its depletion could be identified by sensitivity analysis, such as inflow productivity and water encroachment evolution. This approach has been applied for well T-32 of Tunu field, a mature field in Mahakam, to perform as single-reservoir gas deliverability monitoring by using only flowing parameter data. The “flowing” mode of Pr estimation with actual Gp, gives good performance of CGIP estimation without any shut-in activities, since this well is one of the big gas producer. This model also handled the dynamic activities of operation: well movement, production curtailment and improvement. The unknown variable of continuous water encroachment is also handled by wellbore temperature model which justified with actual data. This improved model could be considered as an alternative approach for gas reserves quantification and gives advantage for production strategy.


Author(s):  
Gen Li ◽  
Yufeng Xing ◽  
Zekun Wang

For rectangular thick plates with non-Levy boundary conditions, it is important to explore analytical free vibration solutions because the classical inverse and semi-inverse exact solution methods are not applicable to this category of problems. This work is to develop an extended separation-of-variable (SOV) method to find closed-form analytical solutions for the free vibration of rectangular Mindlin plates with arbitrary homogeneous boundary conditions. In the extended SOV method, characteristic differential equations and boundary conditions in two directions are obtained by employing the Rayleigh principle and the assumption that the mode functions are in the SOV form, and two transcendental eigenvalue equations are achieved through boundary conditions. But these two eigenvalue equations cannot be solved simultaneously since there are two equations and only the natural frequency is the unknown variable. Considering this, the second assumption in this method is that the natural frequencies corresponding to two-direction mode functions are independent of each other in the mathematical sense, thus there are two unknowns in two transcendental eigenvalue equations, and the closed-form solutions for plates with arbitrary boundary conditions can be obtained non-iteratively. From the physical sense, the natural frequencies pertaining to different direction mode functions should be the same, and this conclusion is validated analytically and numerically. The present natural frequencies and mode shapes agree well with those obtained by other analytical and numerical methods. Especially, for the plates with at least two opposite sides simply supported, the present solutions are exact.


Author(s):  
Daria Aleksandrovna Kuznetsova ◽  
Aleksey Leonidovich Trukhachev ◽  
Violetta Aleksandrovna Rykova ◽  
Olga Nikolaevna Podladchikova

The paper analyzes the siderophore biosynthesis genes that are located in the ysu and ynp loci of only Y. pestis and Y. pseudotuberculosis, have variable structure between different strains of both species and contain previously unknown variable number tandem repeats (VNTR). The purpose of the study was to assess the possibility of using these VNTR as genetic markers for intra-and interspecific differentiation of pathogenic Yersinia. Based on the novel VNTR-markers, three pairs of primers (ysu-interF/R, ilp1F/R и ilp2F/R) were designed and used for the in silico and in vitro PCR analysis of various Y.pestis and Y. pseudotuberculosis strains. All studied Y. pestis strains of the main subspecies (ssp pestis), unlike the strains of non-main subspecies and Y. pseudotuberculosis, did not give amplicon with ilp1F/R primers, since the area between them contains an IS100 element. To identify the strains of the main subspecies, the fourth pair of primers ilp1F-is100R was designed, allowing the most dangerous ssp pestis strains to be distinguished from the not dangerous non-main ssp strains. Y. pseudotuberculosis strains were characterized by a significant variety of amplicons with three pairs of primers, and which made it possible to carry out intraspecies strain genotyping. At the same time, for those strains whose serotype is known, the correlation between the serogroup and the genotype of the strains was observed. Analysis of the 1 serotype strains representing most sequenced Y. pseudotuberculosis strains allowed us to separate two gene groups differing from the rest of 1 serotype gene groups. The first one included the serotype 1a strains isolated from people in Europe, which are known to have the greatest pathogenetic potential. The other one was formed by serotype 1b strains isolated from people in Siberia and Primorye, which are characterized by the high epidemic potential. Thus, four pairs of primers designed in this study can be used to develop additional tests for the identification and differential diagnostics of the most dangerous Y. pestis ssp pestis and Y. pseudotuberculosis serotype 1a and 1b strains.


2021 ◽  
Author(s):  
Scott Thiessen ◽  
Oliver Han ◽  
Ramadan Ahmed ◽  
Rida Elgaddafi

ABSTRACT In hydraulic fracturing, determining the perforation pressure loss is a critical step in the design strategy, on-site troubleshooting diagnostics and post-fracture analysis. Historically, the most widely assumed and thus unknown components in the perforation friction equationare the coefficient of discharge and the holistic perforation diameter. The perforation coefficient of discharge has long been assumed as a dynamic variable dependent on the amount of fluid and proppant pumped through the perforations. This variable becomes increasingly important when clusters are spaced closer together and fewer perforations are shot such as in a limited entry design. Limited entry is a perforating technique used to generate uniform fractures along the wellbore by creating appropriate pressure differentials from cluster to cluster. With the adoption of consistent hole perforating shaped charges, the perforating diameters are more consistent and predictable. While not all consistent hole shaped charges have low diameter variability, the perforating diameters downhole are no longer an unknown, particularly after the introduction of downhole cameras. Therefore, the coefficient of discharge is the only unknown variable remaining. This paper presents an experimental methodology to accurately define the true coefficient of discharge in common completions perforated by a known consistent hole shaped charge. The test setup is illustrated, detailed test steps are discussed, and experimental data with correlations of rate per perforation and discharge coefficient is presented. Completions tested included 4-1/2", 5", and 5-1/2" casings in common weights and grades. Various perforating strategies were examined such as single shot and angled shot. Critical parameters such as entry hole diameters were made by the actual shaped charges and measured before and after the test. Freshwater and slickwater were used as hydraulic fluid and circulated at real-world pump rates through each perforation to simulate the actual field flow conditions. Based on the study, several correlations for the coefficient of discharge of flow through a perforation are created considering casing thickness, entry hole diameter and rate per perforation for the given consistent hole shaped charges. These correlations can improve perforation and fracturing designs where perforation friction are important variables.


2021 ◽  
Vol 22 (4) ◽  
pp. 217-224
Author(s):  
Yu. N. Chelnokov ◽  
A. V. Molodenkov

For the functioning of algorithms of inertial orientation and navigation of strapdown inertial navigation system (SINS), it is necessary to conduct a mathematical initial alignment of SINS immediately before the operation of these algorithms. An efficient method of initial alignment (not calibration!) of SINS is the method of vector matching. Its essence is to determine the relative orientation of the instrument trihedron Y (related to the unit of SINS sensors) and the reference trihedron X according to the results of measuring the projections of at least two non-collinear vectors of the axes on both trihedrons. We address the estimation of the initial orientation of the object using the method of gyrocompassing, which is a form of vector matching method. This initial alignment method is based upon using the projections of the apparent acceleration vector a and the absolute angular velocity vector ω of the object in the coordinate systems X and Y. It is assumed that the three single-axis accelerometers and the three gyroscopes (generally speaking, the three absolute angular velocity sensors of any type), which measure the projections of the vectors a and ω, are installed along the axes of the instrument coordinate system Y. If the projections of the same vectors on the axes of the base coordinate system X are known, then it is possible to estimate the mutual orientation of X and Y trihedrons. We are solving the problem of the initial alignment of SINS for the case of a fixed base, when the accelerometers measure the projection gi (i = 1, 2, 3) of the gravity acceleration vector g, and the gyroscopes measure the projections u i of the vector u of angular velocity of Earth’s rotation on the body-fixed axes. The projections of the same vectors on the axes of the normal geographic coordinate system X are also estimated using the known formulas. The correlation between the projections of the vectors u and g in X and Y coordinate system is given by known quaternion relations. In these relations the unknown variable is the orientation quaternion of the object in the X coordinate system. By separating the scalar and vector parts in the equations, we obtain an overdetermined system of linear algebraic equations (SLAE), where the unknown variable is the finite rotation vector θ, which aligns the X and Y coordinate systems (it is assumed that there is no half-turn of the X coordinate system with respect to the Y coordinate system). Thus, the mathematical formulation of the problem of SINS initial alignment by means of gyrocompassing is to find the unknown vector θ from the derived overdetermined SLAE. When finding the vector θ directly from the SLAE (algorithm 1) and data containing measurement errors, the components of the vector q are also determined with errors (especially the component of the vector θ, which is responsible for the course ψ of an object). Depending on the pre-defined in the course of numerical experiments values of heading ψ, roll ϑ, pitch γ angles of an object and errors of the input data (measurements of gyroscopes and accelerometers), the errors of estimating the heading angle Δψ of an object may in many cases differ from the errors of estimating the roll Δϑ and pitch Δγ angles by two-three (typically) or more orders. Therefore, in order to smooth out these effects, we have used the A. N. Tikhonov regularization method (algorithm 2), which consists of multiplying the left and right sides of the SLAE by the transposed matrix of coefficients for that SLAE, and adding the system regularization parameter to the elements of the main diagonal of the coefficient matrix for the newly derived SLAE (if necessary, depending on the value of the determinant of this matrix). Analysis of the results of the numerical experiments on the initial alignment shows that the errors of estimating the object’s orientation angles Δψ, Δϑ, Δγ using algorithm 2 are more comparable (more consistent) regarding their order.


2021 ◽  
Vol 81 (2) ◽  
Author(s):  
G. A. Carvalho ◽  
F. Rocha ◽  
H. O. Oliveira ◽  
R. V. Lobato

AbstractThe f(R, T) gravity is a theory whose gravitational action depends arbitrarily on the Ricci scalar, R, and the trace of the stress–energy tensor, T; its field equations also depend on matter Lagrangian, $$\mathscr {L}_{m}$$ L m . In the modified theories of gravity where field equations depend on Lagrangian, there is no uniqueness on the Lagrangian definition and the dynamics of the gravitational and matter fields can be different depending on the choice performed. In this work, we have eliminated the $$\mathscr {L}_{m}$$ L m dependence from f(R, T) gravity field equations by generalizing the approach of Moraes in Ref. [1]. We also propose a general approach where we argue that the trace of the energy–momentum tensor must be considered an “unknown” variable of the field equations. The trace can only depend on fundamental constants and few inputs from the standard model. Our proposal resolves two limitations: first the energy–momentum tensor of the f(R, T) gravity is not the perfect fluid one; second, the Lagrangian is not well-defined. As a test of our approach we applied it to the study of the matter era in cosmology, and the theory can successfully describe a transition between a decelerated Universe to an accelerated one without the need for dark energy.


2021 ◽  
Vol 24 ◽  
Author(s):  
Neir Antunes Paes ◽  
Carlos Sérgio Araújo dos Santos ◽  
Tiê Dias de Farias Coutinho

ABSTRACT: Objectives: To propose a methodological path to investigate the coverage and information filling of maternal-infant deaths recorded in the Ministry of Health's Mortality Information System for regional spaces. Methods: Four steps were proposed: 1) Assessment of the completeness of the maternal and child variables, which was measured using the deterministic linkage technique between the Mortality Information System (Sistema de Informações sobre Mortalidade – SIM) and the Live Birth Information System (Sistema de Informações sobre Nascidos Vivos – SINASC); 2) Application of the multiple imputation technique to achieve the total filling of the missing information of the variables; 3) Estimation of death coverage; 4) The Unknown Variable Information Index (Índice de Informação Desconhecida da Variável – IIDV) was measured, which represents the combined effect of data completeness and coverage of deaths. The proposal of the methodological path was exemplified for neonatal deaths in the municipalities of Paraíba that are part of the new classification proposed by the Brazilian Institute of Geography and Statistics (Instituto Brasileiro de Geografia e Estatística – IBGE), as adjacent rural areas, in three triennium periods from 2009 to 2017. Results: The percentage of matching records was 45%. Most of the variables had a percentage of non-completion below 10% and around 17% for the mother's education. Coverages ranged from 75 to 83%. The IIDV for all variables was between 21 and 36% after the linkage. Conclusion: The path of the methodological proposal proved to be effective, which can be replicated to other regions, and can be extended to other categories of deaths such as post-neonatal. The combination of the proposed procedures demands low operating costs and their uses are relatively simple to be applied by the managers and technicians of the vital statistics information systems.


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