فیلترها/جستجو در نتایج    

فیلترها

سال

بانک‌ها




گروه تخصصی











متن کامل


نویسندگان: 

AZIMI RASOOL | SAJEDI HEDIEH

اطلاعات دوره: 
  • سال: 

    2014
  • دوره: 

    7
  • شماره: 

    1
  • صفحات: 

    57-66
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    347
  • دانلود: 

    0
چکیده: 

Identifying clusters or clustering is an important aspect of data analysis. It is the task of grouping a set of objects in such a way those objects in the same group/cluster are more similar in some sense or another. It is a main task of exploratory data mining, and a common technique for statistical data analysis This paper proposed an improved version of K-Means Algorithm, namely Persistent K-Means, which alters the convergence method of K-Means Algorithm to provide more accurate clustering results than the K-Means Algorithm and its variants by increasing the clusters’ coherence. Persistent K-Means uses an iterative approach to discover the best result for consecutive iterations of KMeans Algorithm.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 347

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
نویسنده: 

سیدیان لیلاسادات

اطلاعات دوره: 
  • سال: 

    1396
  • دوره: 

    1
تعامل: 
  • بازدید: 

    315
  • دانلود: 

    249
چکیده: 

لطفا برای مشاهده چکیده به متن کامل (PDF) مراجعه فرمایید.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 315

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 249
نویسندگان: 

GEETHA S. | POONTHALIR G. | VANATHI P.

نشریه: 

VIRTUAL

اطلاعات دوره: 
  • سال: 

    621
  • دوره: 

    1
  • شماره: 

    1
  • صفحات: 

    52-59
تعامل: 
  • استنادات: 

    1
  • بازدید: 

    183
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 183

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 1 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
نویسندگان: 

Jensi r.

اطلاعات دوره: 
  • سال: 

    2019
  • دوره: 

    5
  • شماره: 

    2
  • صفحات: 

    93-106
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    85
  • دانلود: 

    0
چکیده: 

Data clustering is the process of partitioning a set of data objects into meaning clusters or groups. Due to the vast usage of clustering Algorithms in many fields, a lot of research is still going on to find the best and efficient clustering Algorithm to partition the data items. K-Means is simple and easy to implement, but it suffers from initialization of cluster center and hence trapped in local optimum. In this paper, a new hybrid data clustering approach which combines the modified krill herd and K-Means Algorithms, named as K-MKH, is proposed. K-MKH Algorithm utilizes the power of quick convergence behaviour of K-Means and efficient global exploration of Krill Herd and random phenomenon of Levy flight method. The Krill-herd Algorithm is modified by incorporating Levy flight into it to improve the global exploration. The proposed Algorithm is tested on artificial and real life datasets. The simulation results are compared with other methods such as K-Means, Particle Swarm Optimization (PSO), Original Krill Herd (KH), hybrid K-Means and KH. Also the proposed Algorithm is compared with other evolutionary Algorithms such as hybrid modified cohort intelligence and K-Means (K-MCI), Simulated Annealing (SA), Ant Colony Optimization (ACO), Genetic Algorithm (GA), Tabu Search (TS), Honey Bee Mating Optimization (HBMO) and K-Means++. The comparison shows that the proposed Algorithm improves the clustering results and has high convergence speed.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 85

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
اطلاعات دوره: 
  • سال: 

    2021
  • دوره: 

    7
تعامل: 
  • بازدید: 

    102
  • دانلود: 

    0
چکیده: 

Clustering is an unsupervised classification method that focused on grouping data into clusters. The objects in each cluster are very similar but different from the objects in the other clusters. As clustering methods deal with the massive amount of information, many intelligent software agents have been widely utilized clustering techniques to filter, retrieve, and categorize documents that exist on the World Wide Web. Web mining is generally classified under data mining. In data mining, one of the significant clustering centroid-based partitioning methods is the K-Means Algorithm. One of the K-Means Algorithm's challenges is its extreme sensitivity to initial cluster centers' choice, which may yield get stuck in the local optimum if the initial centers are selected randomly. A variant of the K-Means method is the K-Means++ Algorithm, which improves the Algorithm's performance by smart choices of initialization of the cluster centroids. Evolutionary techniques, widely utilized for optimizing clustering methods by providing their prerequisite parameters. The Genetic Algorithm is stochastic and population-based, that applied in optimization problem-solving. This paper proposed a Genetic-based K-Means (GBKM) clustering Algorithm where the clusters' centroids are encoded by chromosomes rather than random initial cluster centroids. The best cluster centers gave by the Genetic Algorithm that maximizes the fitness function, as initial points of the K-Means Algorithm. The results show this model helps increase the K-Means Algorithm's performance by appropriate choice of initialization of the cluster centroids, compared to four other clustering Algorithms.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 102

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0
نویسندگان: 

BANU G.R.

اطلاعات دوره: 
  • سال: 

    2015
  • دوره: 

    5
  • شماره: 

    3
  • صفحات: 

    439-443
تعامل: 
  • استنادات: 

    1
  • بازدید: 

    170
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 170

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 1 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources
نویسندگان: 

KIRINDIS S. | CHATZIS V.

اطلاعات دوره: 
  • سال: 

    2010
  • دوره: 

    19
  • شماره: 

    5
  • صفحات: 

    1328-1337
تعامل: 
  • استنادات: 

    1
  • بازدید: 

    177
  • دانلود: 

    0
کلیدواژه: 
چکیده: 

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 177

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 1 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
اطلاعات دوره: 
  • سال: 

    1399
  • دوره: 

    13
  • شماره: 

    45
  • صفحات: 

    31-46
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    381
  • دانلود: 

    166
چکیده: 

تصمیم گیری در زمینه سرمایه گذاری یکی از مسائل اساسی در مدیریت مالی است. وقتی که سرمایه گذار با گزینه های مختلفی جهت سرمایه گذاری روبرو می گردد بایستی در مورد تعداد دارایی های انتخابی و میزان سرمایه گذاری بر روی هر کدام از آن ها تصمیم گیری نماید. انتخاب ابزار و تکنیک های که بتواند سبدسهام مناسب را تشکیل دهد یکی از اهداف اصلی دنیای سرمایه گذاری است در این مطالعه جهت کمک به تصمیم گیری مطلوب در انتخاب سهام موجود در سبد براساس مدل مارکویتز از الگوریتم کلونی مصنوعی زنبوراستفاده شده است و برای تعیین کارایی این الگوریتم معیار شارپ، معیار ترینر و ریسک نامطلوب آن محاسبه و با سبد تشکیل شده از الگوریتم های ژنتیک و کلونی مورچگان مقایسه گردیده است. نمونه آماری پژوهش شامل شرکت های فعال پذیرفته شده، در بورس اوراق بهادار تهران از سال 1384 تا 1394 است که به روش حذف سیستماتیک انتخاب گردیده اند. نتایج پژوهش نشان می دهد معیار شارپ سبدسهام تشکیل شده از طریق الگوریتم کلونی مصنوعی زنبور نسبت به الگوریتم های ژنتیک و مورچگان عملکرد بهتری دارد، اما هرچند معیار ترینر و ریسک نامطلوب سبد سهام تشکیل شده از طریق الگوریتم کلونی مصنوعی زنبور عملکرد بهتری داشته، ولی از لحاظ آماری این اختلاف معنادار نبوده است.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 381

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 166 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
نویسنده: 

Badban Bahareh | de Pol Jaco van

اطلاعات دوره: 
  • سال: 

    2004
  • دوره: 

    9
تعامل: 
  • بازدید: 

    196
  • دانلود: 

    0
چکیده: 

IN THIS ARTICLE WE PROVIDE AN Algorithm TO VERIFY FORMULAS OF THE FRAGMENT OF RST ORDER LOGIC, CONSISTING OF QUANTI ER FREE LOGIC WITH ZERO, SUCCESSOR AND EQUALITY. WE RST DEVELOP A REWRITE SYSTEM TO EXTRACT AN EQUIVALENT ORDERED (0,S,=)-BDD FROM ANY GIVEN (0,S,=)-BDD. THEN WE SHOW COMPLETENESS OF THE REWRITE SYSTEM. FINALLY WE MAKE AN Algorithm WITH THE SAME RESULT AS THE REWRITE SYSTEM. GIVEN AN ORDERED (0,S,=)-BDDS WE ARE ABLE TO SEE IN CONSTANT TIME WHETHER THE FORMULA IS A TAUTOLOGY, A CONTRADICTION, OR ONLY SATIS ABLE.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 196

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0
نویسندگان: 

Babaei Hamed | Karimpour Jaber | MAVIZI SAJJAD

اطلاعات دوره: 
  • سال: 

    2017
  • دوره: 

    3
  • شماره: 

    1
  • صفحات: 

    45-64
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    258
  • دانلود: 

    0
چکیده: 

University course timetabling problem is one of the hard problems and it must be done for each term frequently which is an exhausting and time consuming task. The main technique in the presented approach is focused on developing and making the process of timetabling common lecturers among different departments of a university scalable. The aim of this paper is to improve the satisfaction of common lecturers among departments and then minimize the loss of resources within departments. The applied method is to use a collaborative search approach. In this method, at first all departments perform their scheduling process locally; then two clustering and traversing agents are used where the former is to cluster common lecturers among departments and the latter is to find unused resources among departments. After performing the clustering and traversing processes, the mapping operation in done based on principles of common lecturers constraint in redundant resources in order to gain the objectives of the problem. The problem’s evaluation metric is evaluated via using fuzzy c-Means clustering Algorithm on common lecturer constraints within a multi agent system. An applied dataset is based on meeting the requirements of scheduling in real world among various departments of Islamic Azad University, Ahar Branch and the success of results would be in respect of satisfying uniform distribution and allocation of common lecturers on redundant resources among different departments.

شاخص‌های تعامل:   مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resources

بازدید 258

مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesدانلود 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesاستناد 0 مرکز اطلاعات علمی Scientific Information Database (SID) - Trusted Source for Research and Academic Resourcesمرجع 0
litScript
telegram sharing button
whatsapp sharing button
linkedin sharing button
twitter sharing button
email sharing button
email sharing button
email sharing button
sharethis sharing button