The possibility of comparing line standards of length photographically

1953 ◽  
Vol 219 (1139) ◽  
pp. 500-515 ◽  
Keyword(s):  
Standard Deviation ◽  
Sufficient Accuracy ◽  
Visual Methods ◽  
Line Position ◽  
Single Measurement ◽  
Photographic Images ◽  
Suitable Definition ◽  
Definition Of ◽  
Better Than

Line standards of length, such as metres or yards, can be compared visually using micrometer microscopes to about one in ten millions in the most precise work. It seems possible that in a photographic comparison appreciably higher precision could be attained with less labour. Photographs of the lines on some line standards have been examined with a densitometer to determine the accuracy with which the distance between two photographic images of such lines could be measured. With suitable definition of line position a single measurement of this distance should have a standard deviation corresponding to less than 0.05 μ . Provided the temperature of the bars is known with sufficient accuracy it should be possible to compare two line standards to much better than one in ten millions in less than half the time taken by present visual methods. A machine for measuring the photographs is suggested. The characteristics of photographs of some lines are given in an appendix.

Resolution and measurement in the scanning electron microscope

1987 ◽  
Vol 45 ◽  
pp. 534-537 ◽  
Author(s):  
Michael T. Postek
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Engineering Design ◽  
Resolving Power ◽  
Practical Applications ◽  
Instrument Resolution ◽  
Accurate Definition ◽  
Definition Of ◽  
Scanning Electron ◽  
Better Than

The term ultimate resolution or resolving power is the very best performance that can be obtained from a scanning electron microscope (SEM) given the optimum instrumental conditions and sample. However, as it relates to SEM users, the conventional definitions of this figure are ambiguous. The numbers quoted for the resolution of an instrument are not only theoretically derived, but are also verified through the direct measurement of images on micrographs. However, the samples commonly used for this purpose are specifically optimized for the measurement of instrument resolution and are most often not typical of the sample used in practical applications.SEM RESOLUTION. Some instruments resolve better than others either due to engineering design or other reasons. There is no definitively accurate definition of how to quantify instrument resolution and its measurement in the SEM.

Using Connectionist Modules for Decision Support

1990 ◽  
Vol 29 (03) ◽  
pp. 167-181 ◽  
Author(s):  
G. Hripcsak
Keyword(s):  
Decision Support ◽  
Standard Deviation ◽  
Confidence Interval ◽  
Posterior Probability ◽  
Back Propagation ◽  
Connectionist Model ◽  
Test Set ◽  
The Third ◽  
Independent Test ◽  
Better Than

AbstractA connectionist model for decision support was constructed out of several back-propagation modules. Manifestations serve as input to the model; they may be real-valued, and the confidence in their measurement may be specified. The model produces as its output the posterior probability of disease. The model was trained on 1,000 cases taken from a simulated underlying population with three conditionally independent manifestations. The first manifestation had a linear relationship between value and posterior probability of disease, the second had a stepped relationship, and the third was normally distributed. An independent test set of 30,000 cases showed that the model was better able to estimate the posterior probability of disease (the standard deviation of residuals was 0.046, with a 95% confidence interval of 0.046-0.047) than a model constructed using logistic regression (with a standard deviation of residuals of 0.062, with a 95% confidence interval of 0.062-0.063). The model fitted the normal and stepped manifestations better than the linear one. It accommodated intermediate levels of confidence well.

An LQ Approach to Active Control of Vibrations in Helicopters

1996 ◽  
Vol 118 (3) ◽  
pp. 482-488 ◽  
Author(s):  
Sergio Bittanti ◽  
Fabrizio Lorito ◽  
Silvia Strada
Keyword(s):  
Optimal Control ◽  
Active Control ◽  
Linear Quadratic ◽  
Control Effort ◽  
Vibration Effect ◽  
Suitable Definition ◽  
Lq Optimal Control ◽  
The One ◽  
Definition Of ◽  
And Control

In this paper, Linear Quadratic (LQ) optimal control concepts are applied for the active control of vibrations in helicopters. The study is based on an identified dynamic model of the rotor. The vibration effect is captured by suitably augmenting the state vector of the rotor model. Then, Kalman filtering concepts can be used to obtain a real-time estimate of the vibration, which is then fed back to form a suitable compensation signal. This design rationale is derived here starting from a rigorous problem position in an optimal control context. Among other things, this calls for a suitable definition of the performance index, of nonstandard type. The application of these ideas to a test helicopter, by means of computer simulations, shows good performances both in terms of disturbance rejection effectiveness and control effort limitation. The performance of the obtained controller is compared with the one achievable by the so called Higher Harmonic Control (HHC) approach, well known within the helicopter community.

scholarly journals Formation of functional-role communication clusters based on morphological features of the verbal context

2020 ◽  
Vol 175 ◽  
pp. 15007 ◽  
Author(s):  
Vladimir Meshkov ◽  
Natalia Kochkovaya ◽  
Irina Usova
Keyword(s):  
Functional Role ◽  
Morphological Analysis ◽  
Sufficient Accuracy ◽  
Morphological Features ◽  
Average Data ◽  
Definition Of

This work combines two approaches to the definition of the author’s style: statistical and linguistic (method of morphological analysis). The average data of the authors obtained on the basis of statisticalmorphological analysis are taken as an indications vector. The article shows that this technique allows to recognize the author’s style of the work with sufficient accuracy, on an average about 88 percent. It is shown that the closest measure of proximity to this technique is the Euclid distance. The prospects for the development of this approach areoutlined.

scholarly journals An orthogonal terrain-following coordinate and its preliminary tests using 2-D idealized advection experiments

2014 ◽  
Vol 7 (4) ◽  
pp. 1767-1778 ◽  
Author(s):  
Y. Li ◽  
B. Wang ◽  
D. Wang ◽  
J. Li ◽  
L. Dong
Keyword(s):  
Rotation Angle ◽  
Computational Grids ◽  
Time Step ◽  
Numerical Errors ◽  
Terrain Following ◽  
Steep Terrain ◽  
Definition Of ◽  
Σ Coordinate ◽  
Basis Vectors ◽  
Better Than

Abstract. We have designed an orthogonal curvilinear terrain-following coordinate (the orthogonal σ coordinate, or the OS coordinate) to reduce the advection errors in the classic σ coordinate. First, we rotate the basis vectors of the z coordinate in a specific way in order to obtain the orthogonal, terrain-following basis vectors of the OS coordinate, and then add a rotation parameter b to each rotation angle to create the smoother vertical levels of the OS coordinate with increasing height. Second, we solve the corresponding definition of each OS coordinate through its basis vectors; and then solve the 3-D coordinate surfaces of the OS coordinate numerically, therefore the computational grids created by the OS coordinate are not exactly orthogonal and its orthogonality is dependent on the accuracy of a numerical method. Third, through choosing a proper b, we can significantly smooth the vertical levels of the OS coordinate over a steep terrain, and, more importantly, we can create the orthogonal, terrain-following computational grids in the vertical through the orthogonal basis vectors of the OS coordinate, which can reduce the advection errors better than the corresponding hybrid σ coordinate. However, the convergence of the grid lines in the OS coordinate over orography restricts the time step and increases the numerical errors. We demonstrate the advantages and the drawbacks of the OS coordinate relative to the hybrid σ coordinate using two sets of 2-D linear advection experiments.

scholarly journals PERBEDAAN PEMAHAMAN KONSEP MATEMATIKA ANTARA SISWA YANG BELAJAR DENGAN MENGGUNAKAN MODEL PEMBELAJARAN KOOPERATIF TIPE JIGSAW DAN KONVENSIONAL

Aksioma ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 171-178
Author(s):  
Siti Hadijah ◽  
Sutji Rochaminah ◽  
Maxinus Jaeng
Keyword(s):  
Standard Deviation ◽  
Cooperative Learning ◽  
Random Sampling ◽  
Hypothesis Test ◽  
Control Design ◽  
Learning Model ◽  
Average Score ◽  
Concept Understanding ◽  
Cluster Random Sampling ◽  
Better Than

Abstrak: Penelitian ini bertujuan untuk mengetahui apakah pemahaman konsep matematika siswa yang belajar dengan menggunakan model pembelajaran kooperatif tipe jigsaw lebih baik daripada pemahaman konsep matematika siswa yang belajar dengan menggunakan model pembelajaran konvensional di Kelas IX MTs Negeri 1 Kota Palu. Hipotesis penelitian ini adalah pemahaman konsep matematika siswa yang belajar dengan menggunakan model pembelajaran kooperatif tipe jigsaw lebih baik daripada pemahaman konsep matematika siswa yang belajar dengan menggunakan pembelajaran konvensional. Jenis penelitian ini adalah eksperimen semu. Desain penelitian ini adalah pre-post test control design. Populasi penelitian ini adalah seluruh siswa kelas IX MTs Negeri 1 Kota Palu dengan teknik pengambilan sampel cluster random sampling. Nilai rata-rata siswa kelas eksperimen 47 dan standar deviasi 17,04 sedangkan nilai rata-rata siswa kelas kontrol 40 dan standar deviasi 13,40. Data yang diperoleh berdistribusi normal dan homogen, maka pengujian hipotesis menggunakan teknis statistik parametris yaitu uji t. Hasil pengujian hipotesis diperoleh bahwa nilai ????tabel = 1,67 dan ????hitung = 2,96 sehingga H1 diterima dan H0 ditolak. Hal ini menunjukkan bahwa pemahaman konsep matematika siswa yang belajar dengan menggunakan model pembelajaran kooperatif tipe jigsaw lebih baik daripada pemahaman konsep matematika siswa yang belajar dengan menggunakan model pembelajaran konvensional di kelas IX MTsN 1 Kota Palu. Kata Kunci:   Model Pembelajaran Kooperatif Tipe Jigsaw, Model Pembelajaran Konvensional,  dan Pemahaman Konsep   Abstract: This research purposed to determine is mathematics concept understanding students who learn by using jigsaw cooperative learning model better than students who learn by using conventional learning model in class IX MTs Negeri 1 Kota Palu. The hypothesis is that mathematics concept understanding students who learn by using jigsaw cooperative learning model better than students who learn by using conventional learning model. The type of research is a quasi experiment. Design of research is pre-post control design. The population of this research is all students of class IX  MTs Negeri 1 Kota Palu with samples taken by cluster random sampling technique. The average score of the experiment class students is 47 and standard deviation is 17.04 and the average score of the control class students is 40 and standard deviation is 13.40. The data is normal distribution and homogen, hypothesis test using t test. Results of hypothesis test obtained value ????table = 1.67 and ????count = 2.96 it means H1 is accepted and H0 is rejected. This indicated that mathematics concept understanding students who learn by using jigsaw cooperative learning model have better than mathematics concept understanding students who learn by using conventional learning model in class IX MTsN 1 Kota Palu. Keywords:  Jigsaw Cooperative Learning Model, Conventional Learning Model, and Concept Understanding

scholarly journals The Median Solution of the Newsvendor Problem and Some Observations

2015 ◽  
Vol 6 (3) ◽  
pp. 55-60
Author(s):  
Pritibhushan Sinha
Keyword(s):  
Standard Deviation ◽  
Theoretical Analysis ◽  
Numerical Experiment ◽  
Objective Function ◽  
Optimization Problems ◽  
Newsvendor Problem ◽  
Expected Profit ◽  
Random Optimization ◽  
Better Than

Abstract We consider the median solution of the Newsvendor Problem. Some properties of such a solution are shown through a theoretical analysis and a numerical experiment. Sometimes, though not often, median solution may be better than solutions maximizing expected profit, or maximizing minimum possible, over distribution with the same average and standard deviation, expected profit, according to some criteria. We discuss the practical suitability of the objective function set and the solution derived, for the Newsvendor Problem, and other such random optimization problems.

scholarly journals Penerapan Model Pembelajaran Kooperatif Tipe Make a Match untuk Meningkatkan Hasil Belajar Siswa pada Materi Larutan Elektrolit dan Non Elekrolit di Kelas X Madrasah Aliya DDI Lonja

2018 ◽  
Vol 7 (1) ◽  
pp. 23
Author(s):  
Muslimah Muslimah ◽  
Kasmudin Mustapa ◽  
Ratman Ratman
Keyword(s):  
Standard Deviation ◽  
Cooperative Learning ◽  
Learning Model ◽  
Control Group ◽  
Control Group Design ◽  
Group Design ◽  
Quasi Experimental ◽  
Experimental Group ◽  
Better Than

This research describes the differences of student’s learning with the application of cooperative learning type make a match in the electrolyte and non-electrolyte at the X grade student’s of the Madrasah Aliya DDI Lonja. This research used quasi experimental with non randomized pretest-posttest control group design. This research was conducted with two groups: XA as the experimental (n=21) XB as the control group (n=18). The data findings means score of experimental group (X1) is 70,5 with the standard deviation 9,6 and the control group (X2) is 62.0 with the standard deviation is 6. Based on the results, the researcher concludes cooperative learning type make a match has better than control class that used conventional learning model.

scholarly journals 2D IPO's for Constant Speed Lines, Curves, NURBS

2019 ◽  
Author(s):  
Valere Huypens
Keyword(s):  
Major Axis ◽  
Pulse Method ◽  
Constant Speed ◽  
Sampled Data ◽  
Reference Pulse ◽  
Production Manager ◽  
Definition Of ◽  
The Right ◽  
2D And 3D ◽  
Better Than

<div>Current constant speed IPO's, usually, use Sampled-data IPO's and constant speed lines use the </div><div>wrong initialized software DDA-ipo's, which make these IPO's unusable. The Bresenham- and </div><div>midpoint IPO's are non-constant speed reference pulse IPO's with bounded inaccuracy.</div><div>By adding an ultra-fast 3-lines algorithm "PRM-cs" to the actual midpoint or Bresenham algorithms, </div><div>we convert these midpoint-ipo's to very fast, constant speed, reference pulse IPO's. </div><div>This applies to 2D-lines, 3D-lines, 2D-curves and 2D-NURBS.</div><div>The PRM-cs measures, in real-time, the length of the discrete curve and the PRM-cs is completely new. </div><div>We define the best IPO, the major axis principle and the LSD-priority. </div><div>The major axis principle holds for the actual 3D-line IPO's. These IPO's are, generally, inaccurate, </div><div>but they can be updated to constant speed 3D-line IPO's, when the production manager agrees.</div><div>The Digital Geometric Geometry (DAG) defines the discrete lines globally, but this global </div><div>definition of a discrete 3D-line, gives discrete 3D-lines whose accuracy is much less than the </div><div>accuracy of the best discrete 3D-lines (e.g. 37% worse).</div><div>We describe the three causes of the inaccurate (imperfect) discrete 3D-lines. </div><div>All existing pulse-rate or PRM-ipo's use a wrong initialization, which deteriorates the accuracy. </div><div>We determine the right initialization for the new PRM-cs and the updated PRM-ipo. </div><div>We propose the benchmark-ipo "listSIM-ipo". This constant speed IPO can, also, be used in real-</div><div>time for every 2D- and 3D-curve. </div><div>The 3rd-degree Trident NURB shows that the constant speed reference pulse method is much </div><div>better than the existing sampled-data methods.</div>

Graded Causation and Normality

2016 ◽  
Author(s):  
Joseph Y. Halpern
Keyword(s):  
Recent Work ◽  
Experimental Philosophy ◽  
Actual Causation ◽  
Definition Of ◽  
Better Than

Recent work in psychology and experimental philosophy has shown that judgments of actual causation are often influenced by consideration of defaults, typicality, and normality. This chapter shows the definition of causality introduced in Chapter 2 can be extended to defaults, typicality, and normality into account. The resulting framework takes actual causation to be both graded and comparative. Thus, it allows us to say that one cause is better than another. Examples showing the power of the approach are considered.

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