scholarly journals Intelligent Fault Inference of Inverters Based on a Three-Layer Bayesian Network

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Sumin Han ◽  
Yongsheng He ◽  
Shuqing Zheng ◽  
Fuzhong Wang
Keyword(s):  
Topological Structure ◽  
Prior Probability ◽  
Inference Model ◽  
Reasoning Abilities ◽  
The Third ◽  
Operation Conditions ◽  
Probability Table ◽  
Information Conflict ◽  
Fault Inference ◽  
Maximum Expectation

A three-layer Bayesian intelligent fault inference model (BIFIM) for an inverter is established to infer the probable uncertain faults. The topological structure of the BIFIM includes the inverter’s operation conditions for the first layer, the inverter’s faults for the second layer, and the fault symptoms for the third layer, which combines the field technicians’ knowledge and experiences with historical running data. The prior probability table of the root node is acquired by the method of basic probabilities corrected historical operation data. The conditional probability parameter table of the BIFIM is obtained by the improved maximum expectation algorithm. Four kinds of incomplete evidence were reasoned and verified, including simple evidence with obvious support, incomplete evidence information, complex evidence without obvious support, and evidence with information conflict. The proposed strategy can make use of the available evidences to inference the probabilities of faults, indicating different reasoning abilities under the different degree of completeness of evidence, especially demonstrating the same inference result under some incomplete evidence information as under complete evidence information.

Contributions of ability and attainment testing in Africa to a general theory of intellect

1969 ◽  
Vol 1 (S1) ◽  
pp. 91-102 ◽  
Author(s):  
S. H. Irvine
Keyword(s):  
General Theory ◽  
Cross Cultural ◽  
Third Order ◽  
Order Analysis ◽  
First Order ◽  
Reasoning Abilities ◽  
The Third ◽  
Factor Analytic ◽  
Similarities And Differences ◽  
Perceptual Styles

SummaryFactor analytic studies in Africa are compared with other cross-cultural investigations into the structure of abilities in different ethnic groups. Similarities and differences are noted; and environmental influences on the acquisition of skills are also summarized. A correlational study of wrong answers to a battery of thirty marker tests given to a group of predominantly Mashona students indicates that efficiency skills of numerical facility and memory remain at the first order of factor extraction, reasoning abilities emerge in second-order analysis, while perceptual styles are present in the third-order level. This study is used to hypothesize, in the context of African systems of thought, the existence of a primary thought mode that asserts itself in conditions involving repeated errors.

scholarly journals MENINGKATKAN KEMAMPUAN PENALARAN MATEMATIS SISWA MELALUI PEMBELAJARAN BERBASIS MASALAH MATERI PELUANG KELAS XI TKRO-A SMKN 4 JAKARTA

2021 ◽  
Vol 1 (4) ◽  
pp. 210-220
Author(s):  
SOPWATILLAH SOPWATILLAH
Keyword(s):  
Action Research ◽  
Mathematical Reasoning ◽  
Problem Based Learning ◽  
Use Patterns ◽  
Reasoning Abilities ◽  
The Third ◽  
Solution Processes ◽  
Reasoning Test ◽  
Learning Mathematics ◽  
Classroom Action Research

This study aims to improve students' mathematical reasoning skills through the application of problem-based learning in class XI TKRO-A SMK Negeri 4 Jakarta which involves 6 students. This research is classroom action research which is carried out in three cycles and each cycle consists of four stages, namely planning, implementation, observation, and reflection. Students are given a test at the end of each cycle to measure their mathematical reasoning ability. The results showed that learning mathematics through the application of problem-based learning can improve mathematical reasoning abilities from pre-study of 39.34 in the first cycle of 67.65 in the second cycle of 72.24 to 74.08 in the third cycle. The conclusion of this study is that the application of problem-based learning can improve students' mathematical reasoning abilities. Improved mathematical reasoning abilities include aspects: the ability to predict answers and solution processes, use patterns and relationships to analyze mathematical situations, draw logical conclusions from statements, and provide explanations using models, facts and relationships in solving problems. The number of students whose mathematical reasoning scores reached or exceeded 75 also increased. In the preliminary study, there were no students whose mathematical reasoning test scores reached or exceeded 75, while in the first cycle as many as 41.18% students, in the second cycle increased to 61.77% students, and in the third cycle increased to 82.35% students. ABSTRAKPenelitian ini bertujuan untuk meningkatkan kemampuan penalaran matematis siswa melalui penerapan pembelajaran berbasis masalah di kelas XI TKRO-A SMK Negeri 4 Jakarta yang melibatkan 6 siswa. Penelitian ini adalah penelitian tindakan kelas (classroom action research) yang dilaksanakan dalam tiga siklus dan tiap siklus terdiri dari empat tahapan, yaitu perencanaan, pelaksanaan, observasi, dan refleksi. Siswa diberikan tes pada setiap akhir siklus untuk mengukur kemampuan penalaran matematis. Hasil penelitian menunjukkan bahwa pembelajaran matematika melalui penerapan pembelajaran berbasis masalah dapat meningkatkan kemampuan penalaran matematis dari pra penelitian sebesar 39,34 siklus I sebesar 67,65 siklus II sebesar 72,24 menjadi 74,08 pada siklus III. Kesimpulan penelitian ini adalah bahwa penerapan pembelajaran berbasis masalah dapat meningkatan kemampuan penalaran matematis siswa. Peningkatan kemampuan penalaran matematis meliputi aspek: kemampuan memperkirakan jawaban dan proses solusi, menggunakan pola dan hubungan untuk menganalisis situasi matematika, menarik kesimpulan logis dari pernyataan, dan memberikan penjelasan dengan menggunakan model, fakta dan hubungan dalam menyelesaikan soal. Jumlah siswa yang nilai penalaran matematisnya mencapai atau melebihi 75 juga mengalami peningkatan. Pada penelitian pendahuluan belum terdapat siswa yang nilai tes penalaran matematisnya mencapai atau melebihi 75, sedangkan pada siklus I sebanyak 41,18% siswa, pada siklus II meningkat menjadi 61,77% siswa, dan pada siklus III meningkat menjadi 82,35% siswa.

scholarly journals Nonlinear MIMO Control of a Continuous Cooling Crystallizer

2012 ◽  
Vol 2012 ◽  
pp. 1-11
Author(s):  
Pedro Alberto Quintana-Hernández ◽  
Raúl Ocampo-Pérez ◽  
Salvador Tututi-Avila ◽  
Salvador Hernández-Castro
Keyword(s):  
Pid Controller ◽  
Closed Loop ◽  
Crystal Size ◽  
Operating Conditions ◽  
Pid Controllers ◽  
Absolute Value ◽  
The Third ◽  
Operation Conditions ◽  
Metastable Zone ◽  
Third Moment

In this work, a feedback control algorithm was developed based on geometric control theory. A nonisothermal seeded continuous crystallizer model was used to test the algorithm. The control objectives were the stabilization of the third moment of the crystal size distribution (μ3) and the crystallizer temperature (T); the manipulated variables were the stirring rate and the coolant flow rate. The nonlinear control (NLC) was tested at operating conditions established within the metastable zone. Step changes of magnitudes ±0.0015 and ±0.5°C were introduced into the set point values of the third moment and crystallizer temperature, respectively. In addition, a step change of ±1°C was introduced as a disturbance in the feeding temperature. Closed-loop stability was analyzed by calculating the eigenvalues of the internal dynamics. The system presented a stable dynamic behavior when the operation conditions maintain the crystallizer concentration within the metastable zone. Closed-loop simulations with the NLC were compared with simulations that used a classic PID controller. The PID controllers were tuned by minimizing the integral of the absolute value of the error (IAE) criterion. The results showed that the NLC provided a suitable option for continuous crystallization control. For all analyzed cases, the IAEs obtained with NLC were smaller than those obtained with the PID controller.

scholarly journals On the theory of errors and least squares

1932 ◽  
Vol 138 (834) ◽  
pp. 48-55 ◽  
Keyword(s):  
Least Squares ◽  
Prior Probability ◽  
Alternative Form ◽  
Probability Of Error ◽  
The Third ◽  
True Value ◽  
Scientific Inference ◽  
Two Measures ◽  
Normal Law

1. In my “Scientific Inference,” chapter V, I found that the usual presentation of the theory of errors of observation needed some modification, even where the probability of error is distributed according to the normal law. One change made was in the distribution of the prior probability of the precision constant h . Whereas this is usually taken as uniform (or ignored), I considered it better to assume that the prior probability that the constant lies in a range dh is proportional to dh/h . This is equivalent to assuming that if h 1 / h 2 = h 3 / h 4 , h is as likely to lie between h 1 and h 2 as between h 3 and h 4 ; this was thought to be the best way of expressing the condition that there is no previous know­ ledge of the magnitude of the errors. The relation must break down for very small h , comparable with the reciprocal of the whole length of the scale used, and for large h comparable with the reciprocal of the step of the scale; but for the range of practically admissible values it appeared to be the most plausible distribution. The argument for this law can now be expressed in an alternative form. The normal law of error is supposed to hold, but the true value x and the pre­cision constant h are unknown. Two measures are made: what is the pro ability that the third observation will lie between them ? The answer is easily seen to be one-third.

Progress report on 21-cm observations at low latitude between longitudes (l 11) 0° and 66°

1967 ◽  
Vol 31 ◽  
pp. 177-179
Author(s):  
W. W. Shane
Keyword(s):  
Preliminary Report ◽  
Progress Report ◽  
Galactic Centre ◽  
Low Latitude ◽  
The Third ◽  
Introductory Lecture ◽  
Centre Region

In the course of several 21-cm observing programmes being carried out by the Leiden Observatory with the 25-meter telescope at Dwingeloo, a fairly complete, though inhomogeneous, survey of the regionl11= 0° to 66° at low galactic latitudes is becoming available. The essential data on this survey are presented in Table 1. Oort (1967) has given a preliminary report on the first and third investigations. The third is discussed briefly by Kerr in his introductory lecture on the galactic centre region (Paper 42). Burton (1966) has published provisional results of the fifth investigation, and I have discussed the sixth in Paper 19. All of the observations listed in the table have been completed, but we plan to extend investigation 3 to a much finer grid of positions.

The orbit of Pluto over a long interval of time

1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer
Keyword(s):  
Periodic Orbit ◽  
Numerical Integration ◽  
Restricted Problem ◽  
Three Dimensional ◽  
The Third ◽  
Circular Restricted Problem ◽  
Resonance Relation

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.

Monte Carlo Algorithms for Moments of Transition Arrays

1988 ◽  
Vol 102 ◽  
pp. 79-81
Author(s):  
A. Goldberg ◽  
S.D. Bloom
Keyword(s):  
Monte Carlo ◽  
State Vector ◽  
Basis Vector ◽  
Collective State ◽  
Dispersion Characteristics ◽  
Dipole Strength ◽  
The Third ◽  
Monte Carlo Algorithms ◽  
Third Moment ◽  
Very High

AbstractClosed expressions for the first, second, and (in some cases) the third moment of atomic transition arrays now exist. Recently a method has been developed for getting to very high moments (up to the 12th and beyond) in cases where a “collective” state-vector (i.e. a state-vector containing the entire electric dipole strength) can be created from each eigenstate in the parent configuration. Both of these approaches give exact results. Herein we describe astatistical(or Monte Carlo) approach which requires onlyonerepresentative state-vector |RV> for the entire parent manifold to get estimates of transition moments of high order. The representation is achieved through the random amplitudes associated with each basis vector making up |RV>. This also gives rise to the dispersion characterizing the method, which has been applied to a system (in the M shell) with≈250,000 lines where we have calculated up to the 5th moment. It turns out that the dispersion in the moments decreases with the size of the manifold, making its application to very big systems statistically advantageous. A discussion of the method and these dispersion characteristics will be presented.

Probe size and 5th-order aberration

1987 ◽  
Vol 45 ◽  
pp. 134-135 ◽  
Author(s):  
Zhifeng Shao
Keyword(s):  
Electron Probe ◽  
Spherical Aberration ◽  
Wave Length ◽  
Cylindrical Symmetry ◽  
Electron Wave ◽  
Third Order ◽  
The Third ◽  
Probe Radius ◽  
Small Probe ◽  
Probe Size

A small electron probe has many applications in many fields and in the case of the STEM, the probe size essentially determines the ultimate resolution. However, there are many difficulties in obtaining a very small probe.Spherical aberration is one of them and all existing probe forming systems have non-zero spherical aberration. The ultimate probe radius is given byδ = 0.43Csl/4ƛ3/4where ƛ is the electron wave length and it is apparent that δ decreases only slowly with decreasing Cs. Scherzer pointed out that the third order aberration coefficient always has the same sign regardless of the field distribution, provided only that the fields have cylindrical symmetry, are independent of time and no space charge is present. To overcome this problem, he proposed a corrector consisting of octupoles and quadrupoles.

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