scholarly journals An Empirical Analysis of Search in GSAT

1993 ◽  
Vol 1 ◽  
pp. 47-59 ◽  
Author(s):  
I. P. Gent ◽  
T. Walsh
Keyword(s):  
Computer Experiments ◽  
Extensive Study ◽  
Hill Climbing ◽  
Average Score ◽  
Approximation Procedure ◽  
Problem Size ◽  
Simple Scaling ◽  
The Mean ◽  
Two Phases ◽  
The Hill

We describe an extensive study of search in GSAT, an approximation procedure for propositional satisfiability. GSAT performs greedy hill-climbing on the number of satisfied clauses in a truth assignment. Our experiments provide a more complete picture of GSAT's search than previous accounts. We describe in detail the two phases of search: rapid hill-climbing followed by a long plateau search. We demonstrate that when applied to randomly generated 3SAT problems, there is a very simple scaling with problem size for both the mean number of satisfied clauses and the mean branching rate. Our results allow us to make detailed numerical conjectures about the length of the hill-climbing phase, the average gradient of this phase, and to conjecture that both the average score and average branching rate decay exponentially during plateau search. We end by showing how these results can be used to direct future theoretical analysis. This work provides a case study of how computer experiments can be used to improve understanding of the theoretical properties of algorithms.

scholarly journals Adaptive fitness landscape for replicator systems: to maximize or not to maximize

2018 ◽  
Vol 13 (3) ◽  
pp. 25 ◽  
Author(s):  
Alexander S. Bratus ◽  
Yuri S. Semenov ◽  
Artem S. Novozhilov
Keyword(s):  
Natural Selection ◽  
Fitness Landscape ◽  
Evolutionary Process ◽  
Hill Climbing ◽  
Adaptive Landscape ◽  
Basic Model ◽  
Mean Fitness ◽  
The Mean ◽  
The Hill ◽  
Fisher’S Fundamental Theorem

Sewall Wright’s adaptive landscape metaphor penetrates a significant part of evolutionary thinking. Supplemented with Fisher’s fundamental theorem of natural selection and Kimura’s maximum principle, it provides a unifying and intuitive representation of the evolutionary process under the influence of natural selection as the hill climbing on the surface of mean population fitness. On the other hand, it is also well known that for many more or less realistic mathematical models this picture is a severe misrepresentation of what actually occurs. Therefore, we are faced with two questions. First, it is important to identify the cases in which adaptive landscape metaphor actually holds exactly in the models, that is, to identify the conditions under which system’s dynamics coincides with the process of searching for a (local) fitness maximum. Second, even if the mean fitness is not maximized in the process of evolution, it is still important to understand the structure of the mean fitness manifold and see the implications of this structure on the system’s dynamics. Using as a basic model the classical replicator equation, in this note we attempt to answer these two questions and illustrate our results with simple well studied systems.

IDENTIFYING THE MOST SUITABLE AREAS FOR SURFACE FLOW WETLAND CONSTRUCTION IN LITHUANIA

2015 ◽  
Author(s):  
Antanas DUMBRAUSKAS ◽  
Nijolė BASTIENĖ ◽  
Petras PUNYS
Keyword(s):  
Constructed Wetlands ◽  
Ecological Status ◽  
Surface Flow ◽  
Gis Analysis ◽  
Proximity Analysis ◽  
Wetland Construction ◽  
The Mean ◽  
Two Phases ◽  
Terrain Features ◽  
Surface Flow Constructed Wetlands

GIS-based approach to find the suitable sites for surface flow constructed wetlands was employed for the Lithuanian river basins with low ecological status. According to the nature of the analysed criteria the flowchart consists of two phases. Criteria used include hydrographical network, soil properties, terrain features, land use, etc. Some of them have strictly defined values (constraints), and other ranges within certain limits (factors). Limited criteria were analysed using rejection principle and influencing factors using proximity analysis and overlay methods. Selecting the potential sites using standard GIS analysis tools there was estimated about 3286 sites for possible wetlands with the mean area of inflow basin about 4 km2 in the basins of water bodies at risk.

An Improved B-hill Climbing Optimization Technique for Solving the Text Documents Clustering Problem

2020 ◽  
Vol 16 (4) ◽  
pp. 296-306 ◽  
Author(s):  
Laith Mohammad Abualigah ◽  
Essam Said Hanandeh ◽  
Ahamad Tajudin Khader ◽  
Mohammed Abdallh Otair ◽  
Shishir Kumar Shandilya
Keyword(s):  
Optimization Technique ◽  
Document Clustering ◽  
Text Clustering ◽  
Hill Climbing ◽  
Text Documents ◽  
Clustering Problem ◽  
Text Document ◽  
Text Information ◽  
Amount Of Knowledge ◽  
The Hill

Background: Considering the increasing volume of text document information on Internet pages, dealing with such a tremendous amount of knowledge becomes totally complex due to its large size. Text clustering is a common optimization problem used to manage a large amount of text information into a subset of comparable and coherent clusters. Aims: This paper presents a novel local clustering technique, namely, β-hill climbing, to solve the problem of the text document clustering through modeling the β-hill climbing technique for partitioning the similar documents into the same cluster. Methods: The β parameter is the primary innovation in β-hill climbing technique. It has been introduced in order to perform a balance between local and global search. Local search methods are successfully applied to solve the problem of the text document clustering such as; k-medoid and kmean techniques. Results: Experiments were conducted on eight benchmark standard text datasets with different characteristics taken from the Laboratory of Computational Intelligence (LABIC). The results proved that the proposed β-hill climbing achieved better results in comparison with the original hill climbing technique in solving the text clustering problem. Conclusion: The performance of the text clustering is useful by adding the β operator to the hill climbing.

scholarly journals PSYCHOLOGICAL PROFILE OF PATIENTS ELIGIBLE FOR BARIATRIC SURGERY

2016 ◽  
Vol 29 (suppl 1) ◽  
pp. 27-30 ◽  
Author(s):  
Graziela Aparecida Nogueira de Almeida RIBEIRO ◽  
Helenice Brizolla GIAMPIETRO ◽  
Lídia Barbieri BELARMINO ◽  
Wilson SALGADO-JÚNIOR
Keyword(s):  
Bariatric Surgery ◽  
Binge Eating ◽  
Average Score ◽  
Psychological Profile ◽  
Psychosocial Characteristics ◽  
The Mean ◽  
Low Levels ◽  
Using Data ◽  
Binge Eating Scale ◽  
To Receive

Abstract Background: The psychologist who works in bariatric surgery has a role to receive, evaluate, prepare and educate the patient who will undergo the surgical procedure. Psychological evaluation becomes important in so far as allows us to obtain data on personal and familiar history and allow tracing of possible psychopathology. Aim: To collect data on psychological evaluations of patients in a bariatric surgery service of a public hospital in order to describe the psychological profile of patients in this service. Method: Data were collected from 827 patients between 2001 and 2015, using data from an interview, Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI) and Binge Eating Scale (BES). Results: The mean age of patients before surgery was 39 years+/- 10, the mean BMI was 51 kg/m²+7, and most patients (81%) were female. The average score on the BDI was 14.8+8 and women had significantly higher scores than men. On the BAI the average score was 11+8 and on the ECAP was 14+8, both with no difference between groups. Conclusions: Psychosocial characteristics of the patients points to the significant presence of indicators of depression, with low levels of anxiety and binge eating.

scholarly journals Talo-calcaneal distraction Ilizarov frame: an ergonomic method to manage intra-articular fractures of calcaneum

2021 ◽  
Vol 12 (7) ◽  
pp. 88-93
Author(s):  
Anoop Raj Singh ◽  
Javed Ahmad ◽  
Vivek Kumar Shrivastava ◽  
Pavneesh Kumar
Keyword(s):  
Average Score ◽  
Intraarticular Fracture ◽  
Type Iv ◽  
Reduction Techniques ◽  
Articular Fractures ◽  
Ilizarov Frame ◽  
Superficial Skin ◽  
The Mean ◽  
Ct Classification

Background: Principle of distraction and an indirect reduction was used to promote healing of fractures and adequate regeneration of cartilage at the subtalar joint. Aims and Objectives: The study was aimed to elaborate and develop role of Ilizarov as an alternative biologicalmethod to manage intraarticular fracture calcaneum with minimal chances of infection. Materials and Methods: Twenty-one patients were studied and the mean age of patients was 40.7 years (span: 20 to 65 years). Sanders CT classification was used to divide into type II, 11 (52.38%); type III, 7 (33.33%) and type IV, 3 (14.28%). The average followup was 17.2 months (range: 6 to 24 months). AOFAS scale for ankle and hindfoot was used for assessment of patients- 7 (33.33%) excellent, 7 (33.33%) good, 3 (14.28%) fair, and 4 (19.04%) poor results. The average score was 81.5 ±12.1. The mean period of treatment was 12 weeks (10 to 14 weeks). Results: On radiological assessment, Bohler’s angle change was 19.7±4.4 degrees to 33.51± 5.7 degrees; angle of Gissane changed from 126.4 ± 6.7 degrees preoperatively to 124.9 ± 6.9 degrees postoperatively; calcanealheight changed 40.14 ± 1.98 mm preoperatively to 43.33 ± 1.87 mm and width changed 45.09 ±3.65 mm preoperatively to 43.09 ±3.16 mm postoperatively and reduction malalignment >10 degrees in 5 patients. Superficial skin infection at wire insertion sites was the most common complication encountered in our cases. Conclusion: Our results with this ergonomic technique in a small number of 21 non-randomised cases with a mean followup of 17.2 years attribute towards an alternate surgical substitute to conventional open reduction techniques in the treatment of intra-articular fractures of calcaneum having lesser rate of complications.

scholarly journals Comparative Effectiveness of Papaya Leaf Stew (Carica Papaya Linn) With Turmeric Acid (Curcuma Domestica Val-Tamarindus Indica) Against Primary Dysmenorrhea

2018 ◽  
Vol 1 (2) ◽  
pp. 120-127
Author(s):  
Yunita Liana
Keyword(s):  
Young Women ◽  
Rating Scale ◽  
Numeric Rating Scale ◽  
Average Score ◽  
Control Group ◽  
P Value ◽  
Primary Dysmenorrhea ◽  
Control Group Design ◽  
Before And After ◽  
The Mean

Young women often feel primary dysmenorrhoea because the hormonal cycles experienced are not stable, this can disrupt the concentration and activity of young women. The principle of back to nature is increasingly popular today, the side effects of chemical drugs can cause new problems, it is one of the driving force of the development of traditional medicine. Papaya leaves contain Vitamin E which can reduce dysmenorrhea. In addition, turmeric acids also contain curcumine and anthocyanins that inhibit cyclooxygenase, thereby reducing the occurrence of inflammation during uterine contractions. The aim of this research is to know the effectiveness of papaya leaf stew with acidic turmeric to primary dysmenorrhea. Type of Research is an experimental study with a Pretest-Posttest Control Group Design design. The sample is 30 people. The research was conducted on December 27, 2017 s.d February 24, 2018 at SMP Negeri 46 Palembang. Instrument to measure pain Numeric Rating Scale. The statistical test used by Wilcoxon and Mann Whitney U. Average score of pain before papaya leaves stem 5.40 ± 0.73 while the mean score of pain after given turmeric acid 5.33 ± 0.61 The mean score of pain after being given papaya leaves stew 3.60 ± 0.91 while the mean score of pain after given turmeric acid 4.06 ± 0.79. There was a difference of mean score of dysmenorrhea pain before and after given papaya leaf stem p value = 0.000. There is difference of mean score of dysmenorrhea pain before and after given turmeric acid p value = 0,002. There was no difference of mean score of dysmenorrhea pain before and after given papaya leaf sting and turmeric acid p value = 0,217. The decoction of papaya leaf and turmeric acid have the same effectiveness in reducing primary dysmenorrhea pain.

scholarly journals EVALUATION OF THE LEARNING PROCESS OF ISLAMIC EDUCATION IN THE IMPLEMENTATION OF CURRICULUM 2013 IN MALUKU TENGAH

2019 ◽  
Vol 4 (1) ◽  
pp. 199
Author(s):  
St. Jumaeda
Keyword(s):  
High School ◽  
Learning Process ◽  
Evaluation Studies ◽  
Islamic Education ◽  
Average Score ◽  
Learning Program ◽  
Maximum Score ◽  
The Mean ◽  
Method Of Evaluation

This research was conducted to obtain information about the learning process of Islamic education at the high school in Maluku Tengah. In this study applied a method of evaluation studies Program, collection of data obtained through the study of documents, interviews, questionnaires and observation. The data is then classified into the category of excellent, good, sufficient, less, and very less, based on standards that have been set. The findings in the evaluation of the learning program at Islamic Education for high school in Maluku Tengah district, shows that the quality of the learning process, including both categories. The learning process is determined by the element or the following aspects; (1) the Teacher's performance is judged by category, with the acquisition of average score 4.14 or 82.79% of the maximum score, (2) Learning Facilities are assessed either by obtaining the average score of 3.71 or 74.17% of the maximum score, (3) Climate class is rated good with the acquisition of the mean score of 3.61 or 72.04% of the maximum score. (4) the attitude of the learners are assessed either by obtaining the average score 4.01 or 80.09% of the maximum score. (5) the learning motivation of learners assessed either by obtaining the average score or 77.71 3.88% of the maximum score. So based on the results of the assesment and the categorisation then determined that the quality of the learning process the Islamic education judged included on the category either, with the acquisition of the average score or 3.88 77.50% of the maximum score.

scholarly journals IMPLEMENTATION OF E-MODULE TROUBLESHOOTING NETWORK SERVICES BASED MOBILE AS ALTERNATIVE MEDIA

Akademika ◽  
2020 ◽  
Vol 9 (02) ◽  
pp. 53-64
Author(s):  
Sirwan Sirwan ◽  
Kamal Kamal
Keyword(s):  
Experimental Design ◽  
Mobile Learning ◽  
Research Method ◽  
Network Services ◽  
Choice Test ◽  
Average Score ◽  
Test Results ◽  
Multiple Choice Test ◽  
Post Test ◽  
The Mean

The purpose of this study was to: (1) knowing the level of practicality e-module based on mobile learning; (2) determine the effectivenes of using system e-module based on mobile learning in skill competency test TKJ.  The research method experimental design one group pre-test and post-test. Data were collected through multiple choice  test given to respondens before being given treatment and after being given treatment, then the data would then be analyzed using tes t. The results of the e-module practicality test throught a questionnaire distributed to students showed that the e-module based on mobile learning practicality used by students, while according to the assessment by the two media experts that e-module based on mobile learning was practical with an average score of 88.9%. Student readiness in UKK has been successfully improved using mobile learning-based e-modules. Increased readiness of students in UKK is in the medium category with a gain score of 0.4%. The T test results indicate that the Sig. (2-tailed) of 0.000 <0.05. The mean pre-test value was 78.6456 with Std.Deviation 4.85293. The highest value is 90.00 and the lowest value is Std.Deviation 6.57910. The highest score was 96.67 and the lowest score was 73.33.

scholarly journals Erlangian Approximations for Finite-Horizon Ruin Probabilities

2002 ◽  
Vol 32 (2) ◽  
pp. 267-281 ◽  
Author(s):  
Soren Asmussen ◽  
Florin Avram ◽  
Miguel Usabel
Keyword(s):  
Ruin Probability ◽  
Risk Model ◽  
Fluid Model ◽  
Ruin Probabilities ◽  
Approximation Procedure ◽  
Exponential Form ◽  
Probability Of Ruin ◽  
Phase Type ◽  
The Matrix ◽  
The Mean

AbstractFor the Cramér-Lundberg risk model with phase-type claims, it is shown that the probability of ruin before an independent phase-type time H coincides with the ruin probability in a certain Markovian fluid model and therefore has an matrix-exponential form. When H is exponential, this yields in particular a probabilistic interpretation of a recent result of Avram & Usabel. When H is Erlang, the matrix algebra takes a simple recursive form, and fixing the mean of H at T and letting the number of stages go to infinity yields a quick approximation procedure for the probability of ruin before time T. Numerical examples are given, including a combination with extrapolation.

Accuracy of the Hill–radial basis function method and the Barrett Universal II formula

2020 ◽  
pp. 112067212090295 ◽  
Author(s):  
Gabor Nemeth ◽  
Laszlo Modis
Keyword(s):  
Radial Basis Function ◽  
Intraocular Lens ◽  
Basis Function ◽  
Function Method ◽  
Theoretical Formula ◽  
Refractive Errors ◽  
Radial Basis ◽  
The Mean ◽  
The Hill ◽  
Radial Basis Function Method

Purpose: The aim was to assess the postoperative results of a biometric method using artificial intelligence (Hill–radial basis function 2.0), and data from a modern formula (Barrett Universal II) and the Sanders–Retzlaff–Kraft/Theoretical formula. Methods: Phacoemulsification and biconvex intraocular lens implantation were performed in 186 cataractous eyes. The diopters of intraocular lens were established with the Hill–radial basis function method, based on biometric data obtained using the Aladdin device. The required diopters of the intraocular lens were also calculated by the Barrett Universal II formula and with the Sanders–Retzlaff–Kraft/Theoretical formula. The differences between the manifest postoperative refractive errors and the planned refractive errors were calculated, as well as the percentage of eyes within ±0.5 D of the prediction error. The mean- and the median absolute refractive errors were also determined. Results: The mean age of the patients was 70.13 years (SD = 10.67 years), and the mean axial length was 23.47 mm (range = 20.72–28.78 mm). The percentage of eyes within a prediction error of ±0.5 D was 83.62% using the Hill–radial basis function method, 79.66% with the Barrett Universal II formula, and 74.01% in the case of the Sanders–Retzlaff–Kraft/Theoretical formula. The mean- and the median absolute refractive errors were not statistically different. Conclusion: Clinical success was the highest when using the biometric method, based on pattern recognition. The results obtained using Barrett Universal II came a close second. Both methods performed better compared to a traditionally used formula.

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