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متن کامل


نویسندگان: 

Haseme Maxam | Rezaei Mehran | Kaedi Marjan

اطلاعات دوره: 
  • سال: 

    2023
  • دوره: 

    10
  • شماره: 

    2
  • صفحات: 

    13-30
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    26
  • دانلود: 

    0
چکیده: 

Textual analysis in the realm of business depends on text-processing techniques borrowed mainly from information retrieval. Yet, these text-processing techniques are not viable in text-based financial forecasting. In this paper, we suggest developing financial home-grown techniques for processing textual data, specifically in the course of scoring words where standard techniques are not appropriate in financial analysis. On that matter, we pursue two issues. First, we examine major information retrieval heuristics, where we find TF-IDF too facile not only in predicting trends but also in generating accurate results (in terms of errors) on large numbers in text-based financial analysis. Second, we work on a new heuristic satisfying financial concerns. We consider the relationship between the publication rate of information and its importance. The proposed heuristic provides results of unmatchable performance in both predicting trends and precision measures. In an additional analysis, we optimize our scheme using a genetic algorithm as an optimization technique and get greater precision. In comparison with TF-IDF, our proposed heuristic conduces to a 38. 5 percent lower error in closeness measures which is again reduced by 16. 46 percent with the help of a genetic algorithm. Our findings suggest that researchers in the field of financial textual analysis should not rely on standard information retrieval heuristics.

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

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اطلاعات دوره: 
  • سال: 

    2020
  • دوره: 

    4
  • شماره: 

    2
  • صفحات: 

    0-0
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    49
  • دانلود: 

    0
چکیده: 

Background: Nowadays, due to the increased publication of articles in various scientific fields, identifying the publishing trends and emerging keywords in the texts of these articles is essential. Objectives: Thus, the present study identified and analyzed the keywords used in the published articles on medical librarianship and information. Methods: In the present investigation, an exploratory and descriptive approach was used to analyze librarianship and information articles published in specialized journals in this field from 1964 to 2019 by applying text mining techniques. The TF-IDF weighting algorithm was applied to identify the most important keywords used in the articles. The Python programming language was used to implement text mining algorithms. Results: The results obtained from the TF-IDF algorithm indicated that the words “, Library”, , “, Patient”, , and “, Inform”,with the weights of 95. 087, 65. 796, and 63. 386, respectively, were the most important keywords in the published articles on medical librarianship and information. Also, the words “, Catalog”, , “, Book”, , and “, Journal”,were the most important keywords used in the articles published between the years 1960 and 1970, and the words “, Patient”, , “, Bookstore”, , and “, Intervent”,were the most important keywords used in articles on medical librarianship and information published from 2015 to 2020. The words “, Blockchain”, , “, Telerehabilit”, , “, Instagram”, , “, WeChat”, , and “, Comic”,were new keywords observed in articles on medical librarianship and information between 2015 and 2020. Conclusions: The results of the present study revealed that the keywords used in articles on medical librarianship and information were not consistent over time and have undergone a change at different periods so that nowadays, this field of science has also changed following the needs of society with the advent and growth of information technologies.

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

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اطلاعات دوره: 
  • سال: 

    1387
  • دوره: 

    14
تعامل: 
  • بازدید: 

    12316
  • دانلود: 

    1209
چکیده: 

امروزه با رشد سریع اطلاعات و داده ها، یافتن اطلاعات مناسب و کارا از اهمیت خاصی برخوردار است. هدف خلاصه سازی خودکار متن، فراهم کردن خلاصه ای از محتویات مطابق با اطلاعات مورد نیاز کاربر است. در این مقاله، نگارندگان ابتدا مفاهیم خلاصه سازی و انواع آن، سپس سیستم های خلاصه ساز موجود، و در نهایت روش خلاصه سازی خودکار متنهای فارسی پیشنهادی را بررسی نموده اند. روش پیشنهادی، ترکیبی از روشهای مبتنی بر گراف،TF-IDF و الگوریتم ژنتیک (Genetic Algorithm) است. در این روش کلمات قبل از امتیازدهی جملات، ریشه یابی می شوند. پس از امتیازدهی، جملات خلاصه با استفاده از الگوریتم ژنتیک (GA) انتخاب می شوند. تابع برازندگی الگوریتم ژنتیک مبتنی بر سه فاکتور شباهت با عنوان، قابلیت خوانایی و پیوستگی است. ارزیابی خلاصه های حاصل از پیاده سازی سیستم پیشنهادی در انتهای مقاله آورده شده است.

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

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

    1399
  • دوره: 

    6
تعامل: 
  • بازدید: 

    308
  • دانلود: 

    253
چکیده: 

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

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اطلاعات دوره: 
  • سال: 

    2020
  • دوره: 

    6
تعامل: 
  • بازدید: 

    199
  • دانلود: 

    0
چکیده: 

Since most of the energy consumption is related to buildings, energy management in smart homes is a major challenge. Personalized recommender systems are a solution to optimize energy consumption by analyzing building energy consumption behaviors. The NILM energy disaggregation technique has been considered in recent years. However, the combination of recommender systems and NILM has received less attention. This paper proposes a personalized NILM-based recommender system that has three main phases: DAE-based NILM, TF-IDF-based text classification, and personalized recommendation. Because of the noise in the energy data, the DAE-based NILM helps detect these noises from the signals. Households’ requirements and interests are identified at this stage. In the second phase, the TF-IDF technique is used to extract meaningful keywords from the advertised optimal tags and assign them a label. Finally, in the third phase, the cosine similarity technique is used to provide some recommendations. This step generates a suggestion for each device that is on the requirement list. The proposed approach was tested using the REDD dataset. The results showed that the accuracy of the recommendation system was about 60%.

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

بازدید 199

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اطلاعات دوره: 
  • سال: 

    2015
  • دوره: 

    3
تعامل: 
  • بازدید: 

    761
  • دانلود: 

    0
چکیده: 

IN THIS PAPER CLASSIFICATION OF PERSIAN DOCUMENTS DERIVED FROM THE STANDARD CONFIGURATION HAMSHAHRI NEWSPAPER TOOK SEVRAL YEARS. TO RUN HOB USE OF NEURAL NETS WITH BACKPRO- PAGATION ALGORITHM AND DEEP BELIEF NETWORK BASED ON DEEP LEARNING THE PYTHON PROGRAMMING LANGUAGE USED. DOCS OF HAMSHAHRI ARE STANDARD XML FILES. EXTRACTION OF TXT, DOC, ID TAGS TO PERFORM PRE-PROCESSING DATA TO CLASSIFY. PREPROCESSING INCLUDE: STEPS MARKINGS, REMOVAL OF SIGNS, REMOVE STOP WORDS AND ETYMOLOGY OF WORDS USING HAZM LIBRARY. AFTER PREPROCESSING USING TF-IDF WEIGHTING VECTOR WEIGHTING MATRIX COMPOSED OF WORDS. AND THEN USING THE MATRIX SVD DIMENSION REDUCTION OF WASTE DROPPED. DECREASED MATRIX AS INPUT FOR THE NEURAL NETWORK ALGORITHM STANDARD USED. AND FOR CATEGORY DEEP BELIEF NET FOR DATA PROCESSING AND OTHER PROCESSES WITH THE USE OF PYTHON LIBRARIES THAT ARE DESIGNED FOR THIS PURPOSE IN THE CONTEXT OF DEEP LEARNING IS DONE. ACTION LEARNING IN NEURAL NETWORK AND A DEEP BELIEF IN THE NETWORK CONDUCTED 100EPOCHES AND VERIFIABLE CRITERIA IN THIS RE-SOLUTION, CALLS, F-AND PERFORMANCE MEASUREMENT OF PERFORMANCE CATEGORIES. ALSO FOUND ON THESE TWO CATEGORIES OF RESULTS SHOW THAT ACCURACY, SPEED AND EFFICIENCY IN THE NETWORK MUCH MORE FAVORABLE DEEP BELIEF PROPAGATION ALGORITHM IS NEURAL NETWORKS.

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نویسندگان: 

VEISI H. | Afaki N. | Parsafard P.

نشریه: 

Scientia Iranica

اطلاعات دوره: 
  • سال: 

    2020
  • دوره: 

    27
  • شماره: 

    3 (Transactions D: Computer Science and Engineering and Electrical Engineering)
  • صفحات: 

    1301-1315
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    87
  • دانلود: 

    0
چکیده: 

This paper addresses automatic keyword extraction in Persian and English text documents. Generally, to extract keywords from a text, a weight is assigned to each token, and words characterized by higher weights are selected as the keywords. This study proposed four methods for weighting the words and compared these methods with ve previous weighting techniques. The previous methods used in this paper include Term Frequency (TF), Term Frequency Inverse Document Frequency (TF-IDF), variance, Discriminative Feature Selection (DFS), and document length normalization based on unit words (LNU). The proposed weighting methods are presented using variance features and include variance to TF-IDF ratio, variance to TF ratio, the intersection of TF and variance, and the intersection of variance and IDF. For evaluation, the documents are clustered using the extracted keywords as feature vectors and by using K-means, Expectation Maximization (EM), and Ward hierarchical clustering methods. The entropy of the clusters and prede ned classes of the documents are used as the evaluation metrics. For the evaluations, this study collected and labeled Persian documents. Results showed that the proposed weighting method, variance to TF ratio, showed the best performance for Persian texts. Moreover, the best entropy was found by variance to TD-IDF ratio for English texts.

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

بازدید 87

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نویسندگان: 

Forootan Faezeh | RABIEI MOHAMMAD

اطلاعات دوره: 
  • سال: 

    2019
  • دوره: 

    2
  • شماره: 

    2
  • صفحات: 

    1-8
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    265
  • دانلود: 

    0
چکیده: 

E-commerce websites, based on their structural ontology, provides access to a wide range of options and the ability to deal directly with manufacturers to receive cheaper products and services as well as receiving comments and ideas of the users on the provided products and services. This is a valuable source of information, which includes a large number of user reviews. It is difficult to check the bulk of the comments published manually and non-automatically. Hence, sentiment analysis is an automated and relatively new field of study, which extracts and analyzes people's attitudes and emotions from the context of the comments. The primary objective of this research is to analyze the content of users' comments on online sale e-commerce websites of handcraft products. Sentiment analysis techniques were used at sentence level and machine learning approach. First, the pre-processing steps and TF-IDF method were implemented on the comments text. Next, the comments text were classified into two groups of products and services comments using Support Vector Machine (SVM) algorithm with 99. 2% accuracy. Finally, the sentiment of comments was classified into three groups of positive, negative and neutral using XGBoost algorithm. The results showed, 95. 23% and 95. 12% accuracies for classification of sentiments in comments about products and services, respectively.

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

بازدید 265

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نویسندگان: 

دانش فرشید | رحیمی فروغ

اطلاعات دوره: 
  • سال: 

    1402
  • دوره: 

    17
  • شماره: 

    2
  • صفحات: 

    150-160
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    84
  • دانلود: 

    0
چکیده: 

زمینه و اهداف: حجم بسیار بالای انتشارات معتبر COVID-19 در سراسر جهان، ضرورت پایش و تحلیل متون علمی COVID-19 را برای پژوهشگران در سطح خرد و برای سیاست گذاران و برنامه ریزان در سطح کلان بیش از پیش آشکار می سازد. به بیان دیگر، نتایج منتج از تحلیل مدارک منتشرشده COVID-19 با روش ها و تکنیک های متن کاوی از جایگاه و اهمیت ویژه ای برای پژوهشگران، سیاست گذاران و برنامه ریزان علوم پزشکی در سطح ملی و بین المللی برخوردار است و ضرورت انجام چنین پژوهشی را بیش از پیش آشکار می سازد. هدف اصلی پژوهش حاضر شناسایی موضوعات نو ظهور و روند تغییر در واژگان علمی در سطح ملی و بین المللی حوزه موضوعی COVID-19 با روش متن کاوی است. مواد و روش کار: نوع پژوهش حاضر، کاربردی است. این پژوهش با استفاده روش متن کاوی و الگوریت م ها و تکنیک های مربوط به آن و همچنین طبقه بندی متون با رویکرد تحلیلی-تطبیقی انجام شده است. جامعه پژوهش حاضر شامل کلیه انتشارات COVID-19 نمایه شده در پایگاهPubMed Central®,(PMC) است. تا تاریخ بیست خردادماه سال 1400 تعداد رکوردهای بازیابی شده از پایگاه PubMed Central®,(PMC)، 160862 مورد بود. از این تعداد 3143 مورد انتشارات ملی و 157719 مورد انتشارات بین المللی COVID-19 است. در این پژوهش از زبان برنامه نویسی پایتون و کتابخانه های مرتبط با این برنامه استفاده شد. مهم ترین واژگان بر اساس وزن دهی TF-IDF نیز شناسایی و گزارش شد. موضوعات نوظهور با توجه به رشد میانگین وزنی، شناسایی شدند. یافته ها: تحلیل داده ها حاکی از آن است که “, covid”, ، “, infect”,و “, cell”,از مهم ترین واژگان بکار رفته در انتشارات بین المللی COVID-19 و “, patient”, ، “, SARS-Cov”,و “, covid”,مهم ترین واژگان انتشارات ملی هستند. نتیجه گیری: در خصوص روند تغییرات واژگان مورد استفاده در انتشارات COVID-19 از مهمترین نتایجی که می توان استنباط نمود تفاوت اساسی بین مهمترین واژه های انتشارات بین المللی با ملی و تاکید پژوهش های بین الملل بر کرونا و عفونت ناشی از آن و در سطح ملی بر بیماران و کرونا است. نتیجه مهم دیگر تغییرات سالانه بوجود آمده در واژه ها در سطح انتشارات ملی و بین المللی است. شایان ذکر است که تغییرات واژه ها به خصوص در انتشارات ملی و بین المللی هم راستا با اتفاقات و رویدادهای مهم علمی است. متن کامل این مقاله به زبان انگلیسی می باشد. لطفا برای مشاهده متن کامل مقاله به بخش انگلیسی مراجعه فرمایید.لطفا برای مشاهده متن کامل این مقاله اینجا را کلیک کنید.

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

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اطلاعات دوره: 
  • سال: 

    2023
  • دوره: 

    11
  • شماره: 

    42
  • صفحات: 

    94-101
تعامل: 
  • استنادات: 

    0
  • بازدید: 

    33
  • دانلود: 

    0
چکیده: 

Fake information, better known as hoaxes, is often found on social media. Currently, social media is not only used to make friends or socialize with friends online, but some use it to spread hate speech and false information. Hoaxes are very dangerous in social life, especially in countries with large populations and ethnically diverse cultures, such as Indonesia. Although there have been many studies on detecting false information, the accuracy and efficiency still need to be improved. To help prevent the spread of these hoaxes, we built a model to identify false information in Indonesian using an ensemble classifier that combines the n-gram method, term frequency-inverse document frequency, and passive-aggressive classifier method. The evaluation process was carried out using 5000 samples from Twitter social media accounts in this study. The testing process is carried out using four schemes by dividing the dataset into training and test data based on the ratios of 90: 10, 80: 20, 70: 30, and 60: 40. The inspection results show that our software can accurately detect hoaxes at 91. 8%. We also found an increase in the accuracy and precision of hoax detection testing using the proposed method compared to several previous studies. The results show that our proposed method can be developed and used in detecting hoaxes in Indonesian on various social media platforms.

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

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