default search action
Rafael Alcalá
Person information
Refine list
refinements active!
zoomed in on ?? of ?? records
view refined list in
export refined list as
2020 – today
- 2024
- [j46]Álvaro Torres-Martos, Augusto Anguita-Ruiz, Mireia Bustos-Aibar, Alberto Ramírez-Mena, María Arteaga, Gloria Bueno, Rosaura Leis, Concepción Maria Aguilera, Rafael Alcalá, Jesús Alcalá-Fdez:
Multiomics and eXplainable artificial intelligence for decision support in insulin resistance early diagnosis: A pediatric population-based longitudinal study. Artif. Intell. Medicine 156: 102962 (2024) - [c31]María Arteaga, Álvaro Torres-Martos, Augusto Anguita-Ruiz, Jesús Alcalá-Fdez, Rafael Alcalá, María José Gacto:
Prediction of Continuous Targets by Explainable Imbalanced Regression from Omics Data in Childhood Obesity. EXPLIMED@ECAI 2024 - 2023
- [j45]María Arteaga, María José Gacto, Marta Galende, Jesús Alcalá-Fdez, Rafael Alcalá:
Enhancing soft computing techniques to actively address imbalanced regression problems. Expert Syst. Appl. 234: 121011 (2023) - [j44]Carmen Biedma-Rdguez, María José Gacto, Augusto Anguita-Ruiz, Rafael Alcalá, Concepción Maria Aguilera, Jesús Alcalá-Fdez:
Learning positive-negative rule-based fuzzy associative classifiers with a good trade-off between complexity and accuracy. Fuzzy Sets Syst. 465: 108511 (2023) - 2022
- [j43]Alberto Segura-Delgado, Augusto Anguita-Ruiz, Rafael Alcalá, Jesús Alcalá-Fdez:
Mining high average-utility sequential rules to identify high-utility gene expression sequences in longitudinal human studies. Expert Syst. Appl. 193: 116411 (2022) - [j42]Carmen Biedma-Rdguez, María José Gacto, Augusto Anguita-Ruiz, Jesús Alcalá-Fdez, Rafael Alcalá:
Transparent but Accurate Evolutionary Regression Combining New Linguistic Fuzzy Grammar and a Novel Interpretable Linear Extension. Int. J. Fuzzy Syst. 24(7): 3082-3103 (2022) - [c30]Álvaro Torres-Martos, Augusto Anguita-Ruiz, Mireia Bustos-Aibar, Sofia Cámara-Sánchez, Rafael Alcalá, Concepción Maria Aguilera, Jesús Alcalá-Fdez:
Human Multi-omics Data Pre-processing for Predictive Purposes Using Machine Learning: A Case Study in Childhood Obesity. IWBBIO (2) 2022: 359-374 - 2021
- [c29]Carmen Biedma-Rdguez, María José Gacto, Rafael Alcalá, Jesús Alcalá-Fdez:
Meta-Fuzzy Items for Fuzzy Association Rules. FUZZ-IEEE 2021: 1-6 - 2020
- [j41]Augusto Anguita-Ruiz, Alberto Segura-Delgado, Rafael Alcalá, Concepción Maria Aguilera, Jesús Alcalá-Fdez:
eXplainable Artificial Intelligence (XAI) for the identification of biologically relevant gene expression patterns in longitudinal human studies, insights from obesity research. PLoS Comput. Biol. 16(4) (2020) - [j40]Alberto Segura-Delgado, María José Gacto, Rafael Alcalá, Jesús Alcalá-Fdez:
Temporal association rule mining: An overview considering the time variable as an integral or implied component. WIREs Data Mining Knowl. Discov. 10(4) (2020)
2010 – 2019
- 2019
- [j39]María José Gacto, José Manuel Soto-Hidalgo, Jesús Alcalá-Fdez, Rafael Alcalá:
Experimental Study on 164 Algorithms Available in Software Tools for Solving Standard Non-Linear Regression Problems. IEEE Access 7: 108916-108939 (2019) - [c28]Augusto Anguita-Ruiz, Alberto Segura-Delgado, Rafael Alcalá, Concepción Maria Aguilera, Jesús Alcalá Fernández:
Describing Sequential Association Patterns from Longitudinal Microarray Data Sets in Humans. IWBBIO (2) 2019: 318-329 - 2018
- [j38]Rafael Alcalá, María José Gacto, Jesús Alcalá-Fdez:
Evolutionary data mining and applications: A revision on the most cited papers from the last 10 years (2007-2017). WIREs Data Mining Knowl. Discov. 8(2) (2018) - 2017
- [j37]Jesús Alcalá-Fdez, Rafael Alcalá, Sergio González, Yusuke Nojima, Salvador García:
Evolutionary Fuzzy Rule-Based Methods for Monotonic Classification. IEEE Trans. Fuzzy Syst. 25(6): 1376-1390 (2017) - 2014
- [j36]Michela Fazzolari, Rafael Alcalá, Francisco Herrera:
A multi-objective evolutionary method for learning granularities based on fuzzy discretization to improve the accuracy-complexity trade-off of fuzzy rule-based classification systems: D-MOFARC algorithm. Appl. Soft Comput. 24: 470-481 (2014) - [j35]María José Gacto, Marta Galende, Rafael Alcalá, Francisco Herrera:
METSK-HDe: A multiobjective evolutionary algorithm to learn accurate TSK-fuzzy systems in high-dimensional and large-scale regression problems. Inf. Sci. 276: 63-79 (2014) - [j34]Marta Galende, María José Gacto, Gregorio I. Sainz, Rafael Alcalá:
Comparison and design of interpretable linguistic vs. scatter FRBSs: Gm3m generalization and new rule meaning index for global assessment and local pseudo-linguistic representation. Inf. Sci. 282: 190-213 (2014) - 2013
- [j33]Rafael Alcalá, Yusuke Nojima, Hisao Ishibuchi, Francisco Herrera:
Special Issue on "Evolutionary Fuzzy Systems" EFSs. Knowl. Based Syst. 54: 1-2 (2013) - [j32]Michela Fazzolari, Bruno Giglio, Rafael Alcalá, Francesco Marcelloni, Francisco Herrera:
A study on the application of instance selection techniques in genetic fuzzy rule-based classification systems: Accuracy-complexity trade-off. Knowl. Based Syst. 54: 32-41 (2013) - [j31]Michela Fazzolari, Rafael Alcalá, Yusuke Nojima, Hisao Ishibuchi, Francisco Herrera:
A Review of the Application of Multiobjective Evolutionary Fuzzy Systems: Current Status and Further Directions. IEEE Trans. Fuzzy Syst. 21(1): 45-65 (2013) - [c27]María José Gacto, Marta Galende, Rafael Alcalá, Francisco Herrera:
Obtaining accurate TSK Fuzzy Rule-Based Systems by Multi-Objective Evolutionary Learning in high-dimensional regression problems. FUZZ-IEEE 2013: 1-7 - [c26]Michela Fazzolari, Rafael Alcalá, Yusuke Nojima, Hisao Ishibuchi, Francisco Herrera:
Improving a fuzzy association rule-based classification model by granularity learning based on heuristic measures over multiple granularities. GEFS 2013: 44-51 - 2012
- [j30]María José Gacto, Rafael Alcalá, Francisco Herrera:
A multi-objective evolutionary algorithm for an effective tuning of fuzzy logic controllers in heating, ventilating and air conditioning systems. Appl. Intell. 36(2): 330-347 (2012) - [j29]Francisco Chávez de la O, Francisco Fernández, Rafael Alcalá, Jesús Alcalá-Fdez, Gustavo Olague, Francisco Herrera:
Hybrid laser pointer detection algorithm based on template matching and fuzzy rule-based systems for domotic control in real home environments. Appl. Intell. 36(2): 407-423 (2012) - [j28]Rafael Alcalá, Yusuke Nojima, Hisao Ishibuchi, Francisco Herrera:
Special Issue on Evolutionary Fuzzy Systems. Int. J. Comput. Intell. Syst. 5(2): 209-211 (2012) - [j27]Francisco Chávez de la O, Francisco Fernández, María José Gacto, Rafael Alcalá:
Automatic Laser Pointer Detection Algorithm for Environment Control Device Systems Based on Template Matching and Genetic Tuning of Fuzzy Rule-Based Systems. Int. J. Comput. Intell. Syst. 5(2): 368-386 (2012) - [c25]Bruno Giglio, Francesco Marcelloni, Michela Fazzolari, Rafael Alcalá, Francisco Herrera:
A case study on the application of instance selection techniques for Genetic Fuzzy Rule-Based Classifiers. FUZZ-IEEE 2012: 1-8 - 2011
- [j26]María José Gacto, Rafael Alcalá, Francisco Herrera:
Interpretability of linguistic fuzzy rule-based systems: An overview of interpretability measures. Inf. Sci. 181(20): 4340-4360 (2011) - [j25]Yusuke Nojima, Rafael Alcalá, Hisao Ishibuchi, Francisco Herrera:
Special issue on evolutionary fuzzy systems. Soft Comput. 15(12): 2299-2301 (2011) - [j24]Rafael Alcalá, Yusuke Nojima, Francisco Herrera, Hisao Ishibuchi:
Multiobjective genetic fuzzy rule selection of single granularity-based fuzzy classification rules and its interaction with the lateral tuning of membership functions. Soft Comput. 15(12): 2303-2318 (2011) - [j23]Rafael Alcalá, María José Gacto, Francisco Herrera:
A Fast and Scalable Multiobjective Genetic Fuzzy System for Linguistic Fuzzy Modeling in High-Dimensional Regression Problems. IEEE Trans. Fuzzy Syst. 19(4): 666-681 (2011) - [j22]Jesús Alcalá-Fdez, Rafael Alcalá, Francisco Herrera:
A Fuzzy Association Rule-Based Classification Model for High-Dimensional Problems With Genetic Rule Selection and Lateral Tuning. IEEE Trans. Fuzzy Syst. 19(5): 857-872 (2011) - [c24]Francisco Fernández, Francisco Chávez de la O, Rafael Alcalá, Francisco Herrera:
Musical genre classification by means of Fuzzy Rule-Based Systems: A preliminary approach. IEEE Congress on Evolutionary Computation 2011: 2571-2577 - [c23]Francisco Chávez de la O, Francisco Fernández, Rafael Alcalá, Jesús Alcalá-Fdez, Francisco Herrera:
Evolutionary learning of a laser pointer detection fuzzy system for an environment control system. FUZZ-IEEE 2011: 256-263 - [c22]María José Gacto, Rafael Alcalá, Francisco Herrera:
Evolutionary Multi-Objective Algorithm to effectively improve the performance of the classic tuning of fuzzy logic controllers for a heating, ventilating and Air Conditioning system. GEFS 2011: 73-80 - [c21]María José Gacto, Rafael Alcalá, Francisco Herrera:
A Double Axis Classification of Interpretability Measures for Linguistic Fuzzy Rule-Based Systems. WILF 2011: 99-106 - 2010
- [j21]Manuel Mucientes, Jesús Alcalá-Fdez, Rafael Alcalá, Jorge Casillas:
A case study for learning behaviors in mobile robotics by evolutionary fuzzy systems. Expert Syst. Appl. 37(2): 1471-1493 (2010) - [j20]María José Gacto, Rafael Alcalá, Francisco Herrera:
Integration of an Index to Preserve the Semantic Interpretability in the Multiobjective Evolutionary Rule Selection and Tuning of Linguistic Fuzzy Systems. IEEE Trans. Fuzzy Syst. 18(3): 515-531 (2010) - [c20]Francisco Chávez de la O, Francisco Fernández, Jesús Alcalá-Fdez, Rafael Alcalá, Francisco Herrera, Gustavo Olague:
Genetic tuning of a laser pointer environment control device system for handicapped people with fuzzy systems. FUZZ-IEEE 2010: 1-8 - [c19]Jesús Alcalá-Fdez, Rafael Alcalá, Francisco Herrera:
A fuzzy associative classification system with genetic rule selection for high-dimensional problems. GEFS 2010: 33-38 - [c18]María José Gacto, Rafael Alcalá, Francisco Herrera:
Analysis of the Performance of a Semantic Interpretability-Based Tuning and Rule Selection of Fuzzy Rule-Based Systems by Means of a Multi-Objective Evolutionary Algorithm. IEA/AIE (2) 2010: 228-238 - [p3]Ignacio Robles, Rafael Alcalá, José Manuel Benítez, Francisco Herrera:
On the Use of Distributed Genetic Algorithms for the Tuning of Fuzzy Rule Based-Systems. Parallel and Distributed Computational Intelligence 2010: 235-261
2000 – 2009
- 2009
- [j19]Rafael Alcalá, Jesús Alcalá-Fdez, María José Gacto, Francisco Herrera:
Improving fuzzy logic controllers obtained by experts: a case study in HVAC systems. Appl. Intell. 31(1): 15-30 (2009) - [j18]Rafael Alcalá, Yusuke Nojima:
Special issue on genetic fuzzy systems: new advances. Evol. Intell. 2(1-2): 1-3 (2009) - [j17]Ignacio Robles, Rafael Alcalá, José Manuel Benítez, Francisco Herrera:
Evolutionary parallel and gradually distributed lateral tuning of fuzzy rule-based systems. Evol. Intell. 2(1-2): 5-19 (2009) - [j16]Jesús Alcalá-Fdez, Rafael Alcalá, María José Gacto, Francisco Herrera:
Learning the membership function contexts for mining fuzzy association rules by using genetic algorithms. Fuzzy Sets Syst. 160(7): 905-921 (2009) - [j15]Manuel Mucientes, Rafael Alcalá, Jesús Alcalá-Fdez, Jorge Casillas:
Learning weighted linguistic rules to control an autonomous robot. Int. J. Intell. Syst. 24(3): 226-251 (2009) - [j14]María José Gacto, Rafael Alcalá, Francisco Herrera:
Adaptation and application of multi-objective evolutionary algorithms for rule reduction and parameter tuning of fuzzy rule-based systems. Soft Comput. 13(5): 419-436 (2009) - [j13]Rafael Alcalá, Pietro Ducange, Francisco Herrera, Beatrice Lazzerini, Francesco Marcelloni:
A Multiobjective Evolutionary Approach to Concurrently Learn Rule and Data Bases of Linguistic Fuzzy-Rule-Based Systems. IEEE Trans. Fuzzy Syst. 17(5): 1106-1122 (2009) - [c17]María José Gacto, Rafael Alcalá, Francisco Herrera:
A Multiobjective Evolutionary Algorithm for Tuning Fuzzy Rule Based Systems with Measures for Preserving Interpretability. IFSA/EUSFLAT Conf. 2009: 1146-1151 - [c16]Ignacio Robles, Rafael Alcalá, José Manuel Benítez, Francisco Herrera:
Distributed Genetic Tuning of Fuzzy Rule-Based Systems. IFSA/EUSFLAT Conf. 2009: 1740-1744 - [c15]Rafael Alcalá, Yusuke Nojima, Francisco Herrera, Hisao Ishibuchi:
Generating single granularity-based fuzzy classification rules for multiobjective genetic fuzzy rule selection. FUZZ-IEEE 2009: 1718-1723 - [c14]María José Gacto, Rafael Alcalá, Francisco Herrera:
Handling High-Dimensional Regression Problems by Means of an Efficient Multi-Objective Evolutionary Algorithm. ISDA 2009: 109-114 - 2008
- [c13]Pietro Ducange, Rafael Alcalá, Francisco Herrera, Beatrice Lazzerini, Francesco Marcelloni:
Knowledge Base Learning of Linguistic Fuzzy Rule-Based Systems in a Multi-objective Evolutionary Framework. HAIS 2008: 747-754 - [p2]Rafael Alcalá, Jesús Alcalá-Fdez, María José Gacto, Francisco Herrera:
On the Usefulness of MOEAs for Getting Compact FRBSs Under Parameter Tuning and Rule Selection. Multi-Objective Evolutionary Algorithms for Knowledge Discovery from Databases 2008: 91-107 - 2007
- [j12]Rafael Alcalá, Jesús Alcalá-Fdez, Francisco Herrera, José Otero:
Genetic learning of accurate and compact fuzzy rule based systems based on the 2-tuples linguistic representation. Int. J. Approx. Reason. 44(1): 45-64 (2007) - [j11]Rafael Alcalá, Jesús Alcalá-Fdez, Jorge Casillas, Oscar Cordón, Francisco Herrera:
Local identification of prototypes for genetic learning of accurate TSK fuzzy rule-based systems. Int. J. Intell. Syst. 22(9): 909-941 (2007) - [j10]Rafael Alcalá, María José Gacto, Francisco Herrera, Jesús Alcalá-Fdez:
A Multi-Objective Genetic Algorithm for Tuning and Rule Selection to Obtain Accurate and Compact Linguistic Fuzzy Rule-Based Systems. Int. J. Uncertain. Fuzziness Knowl. Based Syst. 15(5): 539-557 (2007) - [j9]Rafael Alcalá, Jesús Alcalá-Fdez, María José Gacto, Francisco Herrera:
Rule Base Reduction and Genetic Tuning of Fuzzy Systems Based on the Linguistic 3-tuples Representation. Soft Comput. 11(5): 401-419 (2007) - [j8]Oscar Cordón, Rafael Alcalá, Jesús Alcalá-Fdez, Ignacio Rojas:
Guest Editorial Genetic Fuzzy Systems: What's Next? An Introduction to the Special Section. IEEE Trans. Fuzzy Syst. 15(4): 533-535 (2007) - [j7]Rafael Alcalá, Jesús Alcalá-Fdez, Francisco Herrera:
A Proposal for the Genetic Lateral Tuning of Linguistic Fuzzy Systems and Its Interaction With Rule Selection. IEEE Trans. Fuzzy Syst. 15(4): 616-635 (2007) - [c12]Rafael Alcalá, Jesús Alcalá-Fdez, María José Gacto, Francisco Herrera:
A Multi-Objective Evolutionary Algorithm for Rule Selection and Tuning on Fuzzy Rule-Based Systems. FUZZ-IEEE 2007: 1-6 - [c11]Rafael Alcalá, Jesús Alcalá-Fdez, María José Gacto, Francisco Herrera:
Genetic Learning of Membership Functions for Mining Fuzzy Association Rules. FUZZ-IEEE 2007: 1-6 - 2006
- [j6]Rafael Alcalá, Jesús Alcalá-Fdez, Jorge Casillas, Oscar Cordón, Francisco Herrera:
Hybrid learning models to get the interpretability-accuracy trade-off in fuzzy modeling. Soft Comput. 10(9): 717-734 (2006) - [c10]Rafael Alcalá, Jesús Alcalá-Fdez, Francisco José Berlanga, María José Gacto, Francisco Herrera:
Genetic Lateral and Amplitude Tuning with Rule Selection for Fuzzy Control of Heating, Ventilating and Air Conditioning Systems. IEA/AIE 2006: 452-461 - [c9]Rafael Alcalá, Jesús Alcalá-Fdez, Francisco José Berlanga, María José Gacto, Francisco Herrera:
Improving Fuzzy Rule-Based Decision Models by Means of a Genetic 2-Tuples Based Tuning and the Rule Selection. MDAI 2006: 317-328 - 2005
- [j5]Rafael Alcalá, Jorge Casillas, Oscar Cordón, Antonio González, Francisco Herrera:
A genetic rule weighting and selection process for fuzzy control of heating, ventilating and air conditioning systems. Eng. Appl. Artif. Intell. 18(3): 279-296 (2005) - [c8]Rafael Alcalá, Jesús Alcalá-Fdez, Francisco Herrera, José Otero:
Genetic Learning of the Knowledge Base of a Fuzzy System by Using the Linguistic 2-Tuples Representation. FUZZ-IEEE 2005: 797-802 - 2004
- [c7]Rafael Alcalá, Francisco Herrera:
Genetic tuning on fuzzy systems based on the linguistic 2-tuples representation. FUZZ-IEEE 2004: 233-238 - 2003
- [j4]Rafael Alcalá, José Manuel Benítez, Jorge Casillas, Oscar Cordón, Raúl Pérez:
Fuzzy Control of HVAC Systems Optimized by Genetic Algorithms. Appl. Intell. 18(2): 155-177 (2003) - [j3]Rafael Alcalá, Jorge Casillas, Oscar Cordón, Francisco Herrera:
Linguistic modeling with weighted double-consequent fuzzy rules based on cooperative coevolutionary learning. Integr. Comput. Aided Eng. 10(4): 343-355 (2003) - [j2]Rafael Alcalá, José Ramón Cano, Oscar Cordón, Francisco Herrera, Pedro Villar, Igor Zwir:
Linguistic modeling with hierarchical systems of weighted linguistic rules. Int. J. Approx. Reason. 32(2-3): 187-215 (2003) - [c6]Rafael Alcalá, Jesús Alcalá-Fdez, Jorge Casillas, Oscar Cordón, Francisco Herrera:
Genetic learning of accurate TS models based on local fuzzy prototyping. EUSFLAT Conf. 2003: 105-108 - [p1]Rafael Alcalá, Oscar Cordón, Francisco Herrera:
Combining Rule Weight Learning and Rule Selection to Obtain Simpler and More Accurate Linguistic Fuzzy Models. Modelling with Words 2003: 44-63 - 2002
- [c5]Rafael Alcalá, Jorge Casillas, Oscar Cordón, Francisco Herrera:
Improving Simple Linguistic Fuzzy Models by Means of the Weighted COR Methodology. IBERAMIA 2002: 294-302 - [c4]Rafael Alcalá, Oscar Cordón, Francisco Herrera, Igor Zwir:
Insurance Market Risk Modeling with Hierarchical Fuzzy Rule Based Systems. ICEIS 2002: 325-333 - [c3]Rafael Alcalá, Jorge Casillas, Oscar Cordón, Francisco Herrera, Igor Zwir:
Hybridizing Hierarchical and Weighted Linguistic Rules. SAC 2002: 812-816 - 2001
- [j1]Rafael Alcalá, Jorge Casillas, Oscar Cordón, Francisco Herrera:
Building fuzzy graphs: Features and taxonomy of learning for non-grid-oriented fuzzy rule-based systems. J. Intell. Fuzzy Syst. 11(3-4): 99-119 (2001) - [c2]Rafael Alcalá, Jorge Casillas, Oscar Cordón, Francisco Herrera:
Linguistic modeling with weighted double-consequent fuzzy rules based on cooperative coevolution. EUSFLAT Conf. 2001: 237-240
1990 – 1999
- 1999
- [c1]Rafael Alcalá, Jorge Casillas, Antonio González:
Tuning fuzzy logic controllers for energy efficiency consumption in buildings. EUSFLAT-ESTYLF Joint Conf. 1999: 103-106
Coauthor Index
aka: Jesús Alcalá Fernández
manage site settings
To protect your privacy, all features that rely on external API calls from your browser are turned off by default. You need to opt-in for them to become active. All settings here will be stored as cookies with your web browser. For more information see our F.A.Q.
Unpaywalled article links
Add open access links from to the list of external document links (if available).
Privacy notice: By enabling the option above, your browser will contact the API of unpaywall.org to load hyperlinks to open access articles. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the Unpaywall privacy policy.
Archived links via Wayback Machine
For web page which are no longer available, try to retrieve content from the of the Internet Archive (if available).
Privacy notice: By enabling the option above, your browser will contact the API of archive.org to check for archived content of web pages that are no longer available. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the Internet Archive privacy policy.
Reference lists
Add a list of references from , , and to record detail pages.
load references from crossref.org and opencitations.net
Privacy notice: By enabling the option above, your browser will contact the APIs of crossref.org, opencitations.net, and semanticscholar.org to load article reference information. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the Crossref privacy policy and the OpenCitations privacy policy, as well as the AI2 Privacy Policy covering Semantic Scholar.
Citation data
Add a list of citing articles from and to record detail pages.
load citations from opencitations.net
Privacy notice: By enabling the option above, your browser will contact the API of opencitations.net and semanticscholar.org to load citation information. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the OpenCitations privacy policy as well as the AI2 Privacy Policy covering Semantic Scholar.
OpenAlex data
Load additional information about publications from .
Privacy notice: By enabling the option above, your browser will contact the API of openalex.org to load additional information. Although we do not have any reason to believe that your call will be tracked, we do not have any control over how the remote server uses your data. So please proceed with care and consider checking the information given by OpenAlex.
last updated on 2024-12-10 21:41 CET by the dblp team
all metadata released as open data under CC0 1.0 license
see also: Terms of Use | Privacy Policy | Imprint