scholarly journals Prediction of strontium bromide laser efficiency using cluster and decision tree analysis

2018 ◽  
Vol 167 ◽  
pp. 04002
Author(s):  
Iliycho Iliev ◽  
Snezhana Gocheva-Ilieva ◽  
Chavdar Kulin
Keyword(s):  
Electrical Power ◽  
Regression Tree ◽  
Biological Tissues ◽  
Maximum Efficiency ◽  
Laser Efficiency ◽  
Tree Models ◽  
Regression Techniques ◽  
Minimal Damage ◽  
Output Characteristics ◽  
Cluster Methods

Subject of investigation is a new high-powered strontium bromide (SrBr2) vapor laser emitting in multiline region of wavelengths. The laser is an alternative to the atom strontium lasers and electron free lasers, especially at the line 6.45 μm which line is used in surgery for medical processing of biological tissues and bones with minimal damage. In this paper the experimental data from measurements of operational and output characteristics of the laser are statistically processed by means of cluster analysis and tree-based regression techniques. The aim is to extract the more important relationships and dependences from the available data which influence the increase of the overall laser efficiency. There are constructed and analyzed a set of cluster models. It is shown by using different cluster methods that the seven investigated operational characteristics (laser tube diameter, length, supplied electrical power, and others) and laser efficiency are combined in 2 clusters. By the built regression tree models using Classification and Regression Trees (CART) technique there are obtained dependences to predict the values of efficiency, and especially the maximum efficiency with over 95% accuracy.

scholarly journals Restoring steppe landscapes: patterns, drivers and implications in Russia’s steppes

2020 ◽  
Author(s):  
Robert Pazur ◽  
Alexander V. Prishchepov ◽  
Ksenya Myachina ◽  
Peter H. Verburg ◽  
Sergey Levykin ◽  
...  
Keyword(s):  
Land Use ◽  
Agricultural Land ◽  
Landsat Imagery ◽  
Regression Tree ◽  
Agricultural Land Use ◽  
Virgin Land ◽  
Human Footprint ◽  
Steppe Belt ◽  
Tree Models ◽  
Southern Russia

Abstract Context Agricultural land abandonment across the steppe belt of Eurasia has provided an opportunity for the restoration of steppe landscapes in recent decades. However, global food demands are about to revert this trajectory and put restored steppe landscapes at risk. Objectives We analysed steppe development in southern Russia in the last 40 years, assessed its spatial patterns and drivers of change for several periods. Methods Using Landsat imagery, we mapped the permanent steppe and steppe restoration from 1990 to 2018. Based on regression tree models, we evaluate and explain its dynamics. Results were compared with district-level trends in land-use intensities of cropland. Results We found 70% of the steppe in 2018 represented permanent steppe and 30% of former cropland dominantly abandoned in the postsocialism (1990–2000). The permanent steppe and steppe restored in the postsocialism (1990–2000) were located far from settlements, on rough terrain and in districts of the Virgin Land Campaign (1954–1963). In recent decades, the patterns of steppe restoration (2000–2018) were mostly determined by unfavourable agroclimatic conditions and distance from grain storage facilities. The restoration pattern reflects regional differences in land-use intensities, e.g., isolated steppe patches mostly appeared in areas of intensive agricultural land-use. Conclusions Steppe restoration has appeared in areas marginal for agricultural production, with poor natural conditions and little human footprint. Consequently, the permanent steppe became less fragmented and a more continuous steppe landscape resulted. The remaining isolated steppe patches require attention in restoration programs as they are mostly located in areas of intensive agricultural land-use.

Abstraction Regression & Tree Models

2021 ◽  
pp. 5-36
Author(s):  
Shuai Huang ◽  
Houtao Deng
Keyword(s):  
Regression Tree ◽  
Tree Models

scholarly journals A Frequency Locking Method for ICPT System Based on LCC/S Compensation Topology

Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2626
Author(s):  
Yansong Li ◽  
Minhao Wang ◽  
Weiwei Zhang ◽  
Mengmeng Zhao ◽  
Jun Liu
Keyword(s):  
Output Power ◽  
Power Transmission ◽  
Transmission Efficiency ◽  
Maximum Efficiency ◽  
Initial Value ◽  
Frequency Locking ◽  
Inductively Coupled ◽  
Output Characteristics ◽  
The Relationship

Aiming to maximize the transmission efficiency of inductively coupled power transmission (ICPT) system with the designed output power, a frequency locking method for an ICPT system based on LCC/S compensation topology is proposed in this paper. Firstly, the relationship between compensation component Lf1 and output power was deduced by the lossless model, and the initial value of Lf1 was obtained. Then, considering the system loss, the designed output power and frequency were input into the frequency locking program, and Lf1 and other compensation parameters were dynamically tracked. At the same time, the transmission efficiency of the system was calculated, and the frequency that achieved maximum efficiency was automatically locked when the system met the requirements of the designed output power. Finally, based on the method, the output characteristics of the system were verified by experiments.

P4-044: IDENTIFICATION OF PHENOTYPIC CLUSTERS OF AD PATIENTS AND CONTROLS USING CLASSIFICATION AND REGRESSION TREE MODELS

2014 ◽  
Vol 10 ◽  
pp. P798-P799
Author(s):  
Charlotte Teunissen ◽  
Niki S.M. Schoonenboom ◽  
Pieter Jelle Visser ◽  
Wiesje M. Van der Flier ◽  
Dirk Knol ◽  
...  
Keyword(s):  
Regression Tree ◽  
Classification And Regression Tree ◽  
Tree Models ◽  
Classification And Regression

Controlled Destruction and Temperature Distributions in Biological Tissues Subjected to Monoactive Electrocoagulation

1980 ◽  
Vol 102 (1) ◽  
pp. 42-49 ◽  
Author(s):  
A. Erez ◽  
A. Shitzer
Keyword(s):  
Electrical Power ◽  
Thermal Inertia ◽  
Spherical Geometry ◽  
Blood Perfusion ◽  
Biological Tissues ◽  
Thermal Recovery ◽  
Temperature Fields ◽  
Tissue Destruction ◽  
Prolonged Heating ◽  
Time Of Application

An analysis of the temperature fields developed in a biological tissue undergoing a monoactive electrical coagulating process is presented, including thermal recovery following prolonged heating. The analysis is performed for the passage of alternating current and assumes a homogeneous and isotropic tissue model which is uniformly perfused by blood at arterial temperature. Solution for the one-dimensional spherical geometry is obtained by a Laplace transform and numerical integrations. Results obtained indicate the major role which blood perfusion plays in determining the effects of the coagulating process; tissue temperatures and depth of destruction are drastically reduced as blood perfusion increases. Metabolic heat generation rate is found to have negligible effects on tissue temperatures whereas electrode thermal inertia affects temperature levels appreciably. However, electrodes employed in practice would have a low thermal inertia which might be regarded as zero for all practical purposes. It is also found that the depth of tissue destruction is almost directly proportional to the electrical power and duration of application. To avoid excessively high temperatures and charring, it would be advantageous to reduce power and increase the time of application. Results of this study should be regarded as a first approximation to the rather complex phenomena associated with electrocoagulation. They may, nevertheless, serve as preliminary guidelines to practicing surgeons applying this technique.

An Experimental Study of the Performance of the Counter-Rotating Wave Energy Conversion Turbine

1989 ◽  
Vol 111 (3) ◽  
pp. 167-173 ◽  
Author(s):  
M. E. McCormick ◽  
S. W. Surko
Keyword(s):  
Experimental Study ◽  
Energy Conversion ◽  
Water Column ◽  
Wave Energy ◽  
Electrical Power ◽  
Wave Crest ◽  
Maximum Efficiency ◽  
Wave Energy Conversion ◽  
Conversion System ◽  
Energy Conversion System

Results of an experimental study of a counter-rotating turbine operating on a pneumatic wave energy conversion system are presented. The vertical capture chamber of the water column of the system has a down-facing water intake. An electrical generator (d-c) is coupled to the turbine by a ten-gear-ratio drive train. Tests of the pneumatic wave energy conversion system were conducted with the mouth at two depths in order to vary the natural oscillating frequency of the water column. The maximum electrical power output of the system was approximately 90 W in the monochromatic waves. This value corresponds to a 36-percent efficiency based on the incident wave power in a wave crest width equal to the diameter of the capture chamber. The theoretical maximum efficiency of such a system has been shown to be 50 percent by several investigators.

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