scholarly journals Non-isomorphic 2-perfect 6-cycle systems of order 13

1991 ◽  
Vol 44 (3) ◽  
pp. 381-385 ◽  
Author(s):  
Rebecca A.H. Gower
Keyword(s):  
Computer Search ◽  
Cycle Systems

Running a computer search for new, cyclic, 2-perfect 6-cycle systems of order 13 and constructing the quasigroups which arise from such systems enabled the author to establish that there are at most two such non-isomorphic systems. Then by using two-variable laws of the quasigroups it is shown that there are exactly two non-isomorphic 2-perfect 6-cycle systems of order 13 which are cyclic.

Machine Learning of Motor Vehicle Accident Categories from Narrative Data

1996 ◽  
Vol 35 (04/05) ◽  
pp. 309-316 ◽  
Author(s):  
M. R. Lehto ◽  
G. S. Sorock
Keyword(s):  
Machine Learning ◽  
Bayesian Model ◽  
Keyword Search ◽  
Motor Vehicle ◽  
Motor Vehicle Accident ◽  
Computer Search ◽  
Vehicle Accident ◽  
Learning Technique ◽  
Expert Ratings ◽  
Keyword Searches

Abstract:Bayesian inferencing as a machine learning technique was evaluated for identifying pre-crash activity and crash type from accident narratives describing 3,686 motor vehicle crashes. It was hypothesized that a Bayesian model could learn from a computer search for 63 keywords related to accident categories. Learning was described in terms of the ability to accurately classify previously unclassifiable narratives not containing the original keywords. When narratives contained keywords, the results obtained using both the Bayesian model and keyword search corresponded closely to expert ratings (P(detection)≥0.9, and P(false positive)≤0.05). For narratives not containing keywords, when the threshold used by the Bayesian model was varied between p>0.5 and p>0.9, the overall probability of detecting a category assigned by the expert varied between 67% and 12%. False positives correspondingly varied between 32% and 3%. These latter results demonstrated that the Bayesian system learned from the results of the keyword searches.

scholarly journals Water Extraction from Air: A Proposal for a New Indicator to Compare Air Water Generators Efficiency

Energies ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 224
Author(s):  
Lucia Cattani ◽  
Anna Magrini ◽  
Paolo Cattani
Keyword(s):  
Energy Efficiency ◽  
Comprehensive Evaluation ◽  
Specific Energy Consumption ◽  
Energy Performance ◽  
Water Extraction ◽  
Coefficient Of Performance ◽  
Efficiency Evaluation ◽  
Evaluation Approach ◽  
Cycle Systems ◽  
Definition Of

Water extraction from air, based on reverse cycle systems, is becoming a technology more and more diffused and various models of air to water generators (AWG) are now available, all claiming the best efficiency. To date, there is not a standard indicator stating energy efficiency for AWGs, neither in the literature nor in technical practice. The only evaluation parameter, that can be found is a sort of specific energy consumption (SEC) without any clear indications about the involved calculation terms, definition of hypotheses, or environmental conditions. The current work is a first proposal of an indicator to standardise the AWG efficiency evaluation. The indicator is called WET (Water Energy Transformation); it states water production as a useful effect of an AWG machine and calculates its energy performance with an approach similar to COP (Coefficient of Performance) and EER (Energy Efficiency Ratio) evaluation. The indicator is meant to be a normalised tool that permits comparing different AWG machines, but it is also the first part of a wider study, currently under development that is oriented to obtain a global index formulation that combines WET itself, EER and COP, and it is intended for a comprehensive evaluation of all the useful effects of a reverse cycle in integrated machines, in compliance with the current efficiency evaluation approach. The current paper presents the WET equation, with a discussion about involved terms, a set of normalised calculation conditions and some application examples, including a comparison with SEC.

A New Category of Three-Dimensional Chaotic Flows with Identical Eigenvalues

2020 ◽  
Vol 30 (02) ◽  
pp. 2050026 ◽  
Author(s):  
Zahra Faghani ◽  
Fahimeh Nazarimehr ◽  
Sajad Jafari ◽  
Julien C. Sprott
Keyword(s):  
Chaotic Systems ◽  
Autonomous Systems ◽  
Three Dimensional ◽  
Special Property ◽  
Computer Search ◽  
Chaotic Flows ◽  
Stable Equilibria ◽  
Dynamical Properties ◽  
Simple Systems ◽  
First Time

In this paper, some new three-dimensional chaotic systems are proposed. The special property of these autonomous systems is their identical eigenvalues. The systems are designed based on the general form of quadratic jerk systems with 10 terms, and some systems with stable equilibria. Using a systematic computer search, 12 simple chaotic systems with identical eigenvalues were found. We believe that systems with identical eigenvalues are described here for the first time. These simple systems are listed in this paper, and their dynamical properties are investigated.

Categorization and analysis of heat sources for organic Rankine cycle systems

2016 ◽  
Vol 64 ◽  
pp. 790-805 ◽  
Author(s):  
Huixing Zhai ◽  
Qingsong An ◽  
Lin Shi ◽  
Vincent Lemort ◽  
Sylvain Quoilin
Keyword(s):  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Heat Sources ◽  
Cycle Systems

Evidence for a separate type of migraine with aura

Neurology ◽  
2003 ◽  
Vol 60 (4) ◽  
pp. 595-601 ◽  
Author(s):  
Lise L. Thomsen ◽  
Elsebet Ostergaard ◽  
Jes Olesen ◽  
Michael B. Russell
Keyword(s):  
Migraine With Aura ◽  
Telephone Interview ◽  
Clinical Symptoms ◽  
Familial Hemiplegic Migraine ◽  
Computer Search ◽  
Hemiplegic Migraine ◽  
Motor Weakness ◽  
National Patient Register ◽  
National Patient ◽  
Sequential Appearance

Objective: To compare clinical characteristics of patients with sporadic hemiplegic migraine (SHM) with those of patients with migraine with typical aura (MA) and patients with familial hemiplegic migraine (FHM).Methods: The authors used a computer search of Denmark’s National Patient Register to screen the population for patients with migraine with aura with motor weakness, and also examined case records from headache clinics and private practicing neurologists and placed advertisements. The authors screened patients and their relatives with a semi-structured validated telephone interview. All recruited patients were then interviewed by a physician and given a neurologic examination.Results: A total of 105 patients with SHM were identified. Seventy-two percent had four typical aura symptoms: visual, sensory, aphasic, and motor. All had at least two symptoms present during SHM attacks. A gradual progression and sequential appearance of aura symptoms was typical; compared with MA, the duration of each aura symptom was usually prolonged and bilateral motor symptoms were more frequent. Of the patients with SHM, 72% fulfilled the criteria for basilar migraine during SHM attacks. The aura was usually followed by headache, as is common in FHM but not MA.Conclusions: Patients with sporadic hemiplegic migraine had clinical symptoms identical to familial hemiplegic migraine and significantly different from migraine with typical aura. Sporadic hemiplegic migraine is a separate entity, and should be classified with familial hemiplegic migraine.

Sign in / Sign up

Export Citation Format

Share Document