CINXE.COM

<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="120"></head><body class="no-js"><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "publications.waset.org",cType: 'non-interactive',cRay: '91369266290e3dad',cH: 'oU7Bg5HgxIYA.wCwxvnl5DIiHa6zeMkqEZZXHsf_P4Y-1739803638-1.2.1.1-77kXwVhq282rzbQpIHiseT0M.1CH1j94XlSSaIajYjY.9rqVicuFzSBYnb7ATPba',cUPMDTk: "\/abstracts\/search?q=recommendation&__cf_chl_tk=QZYN4kbKGJgIgeQEWxOtl.J_kh.hW2YbB5VaHPQ_wsk-1739803638-1.0.1.1-i_JRvsB8l4dCwyDR7Kzr9t9fbWFECpUMdkH3v82AjtM",cFPWv: 'b',cITimeS: '1739803638',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/abstracts\/search?q=recommendation&__cf_chl_f_tk=QZYN4kbKGJgIgeQEWxOtl.J_kh.hW2YbB5VaHPQ_wsk-1739803638-1.0.1.1-i_JRvsB8l4dCwyDR7Kzr9t9fbWFECpUMdkH3v82AjtM",md: "wu6RS9WzZo2HzlhZMZQE2b2TBkMbw1HpUJznrzpSgPI-1739803638-1.2.1.1-gZbvjoX2R7WvIMeUmvJ3.zEdnoWTjFE0zRnUFKbpq6Yc14R9UTMKYemf3JGpa1K2Dl0m5Dm8qDSPo6wvU6tsqI8HY0fU.7DGG7ubbgu_ubYY_5pC2GsUXuZhdVw3n4I6NCuPQdFdQLWYK8uRT30ZcMflwfmZEwkJlQ5vHthS4jdpc2zrdi2CFW7fYVQ5VtQlnI4gXj058yejeX4EOKiGJhhZeZSHtJMZ1N2APPq85Bi6wdvRVMiaVFdTe47mLw0zJ1KZeBQcyZypBA24JEQoWVjRPFnjOJVDfIzvaAM.KK.rtiIfIGNWnXLTTvMTesq86eyfLrTFQ1IlEiG5c.s10e1zk48BHHt..zx3g75bSk27JAVoxU4fTU10tHJBJtAzmKyvYWXagEmYEnY8FE3UKefpT5W3QSmuQCHE6kOrRLbx7M8_PtREKFWMgz9RdYu2YxMf.BZsCugmzFCslCvkooV_DixD5O0Rvlb7atAbPqCr5t6F9aYHl_hzAKNc9RPxnfNoBaDMShNyfuAajoh7FlfBOka6Z2kUeGfDxI9IqurbPwd1n4WCkv.OsJmfFkBbh0dSfAnBc4k_2wUDv5laIsEqaBXRI7ZT0objdzhwehIDVSp9wVjDlFLx6gp09DYqmxOvdH6To4fvAl4vwnONe6wPFtzmbnJHIT4qbVIRK_D_z1nrxVLwdDAv.Gb4X_icFy6HqB4ksvnU7ym3_lJuF_jeelg2slrDrYbmy728d7iAts1K2h_TA.WUi0_GypZonXtPdVCiLpNZDvqSiFuRBqrffv56W_l3Bw8Y25FiVZW4tbcNtl3VSZDV2LrMZG5IFQkk2KGTQccOBZ9_P04WCMYJavDE3C.vywurDZ_iaA1r.rTJAbMQSnnL5hUoFx0tva7sfLYRsrkmUpBE_5XzQsDm_eI5eIm0rXce_L62r9gfN2cxS8TQNGpSrgjtUMO27hDnCowuM3C37n0E7TFrFZ2Xa6tvW.P_kr4MmVVD1e77FEoPz30d7d.tAtWdK87k3Dj8Suf3LGg51nPzZYtXF2ej7LULAQ94CNNmA5Hr1D7Vn.SG3tCfiBGfVgHSlbQnseZ54fFOk7WXL4MYtt4T3LgMW0nIK0I8v4Cy92cRyHLLlYL2uiDhchMaJBfemcrmi7MRztKwVZVwcaj2mL11hvUQrXPODFuMIQpo3kN8MklW7EkmTYovdnSXQoTS2Xcql9H571jo8rkaw5iMMPsYOxb7NfkNKya1VIxkbsoy79iDP08mWPnhTFxbnIqVVuTza5Gh0scbesJY4obhdQqRUkG4SA2WmY9b77rkAPQkPN8_haEiiEHp6prPqcNN38hPQWycE5g2EqsB_Pvs48CasZA9TdYb46odmri8t_8DTKNJr7Abk8XkQ9vsV6Q3fyxDmveuy1jaCyqWp.A4gTHmsXURKFEEBNqptc9NFGCuSj4vEyJ96EVXScQpECCjjBs93F__Kcl1cJMHMaOmCXvVmgdS8w5VIMnO.DdrsBWXHvH1EuR4R6QvRenFiwDKOGJJKiZaG81D4NbEEPblXi6Cda1yMlTWH0RWH38ya5mwtHIQ0q_YMSZmj19V34JcI9V31TjUJGQPkojqgT1RjtASq3wH5.to4CkCWO.axmTRjsjBYbm5Gdo7Uob1_XzTvPnd9F5EuJacelizOVS0wyaroAfiLDtUqBNB1D7xlrIjag2guxfEbl561xFnmrnG0tcRUMdr5HdjGDdhVZTOai21KwuUiyeJRp3XzU8kyv.THBYhOHbaM7_om_RzXY8jacSFJ_b4IL_o3627QuhKO6Amu1a9gNmM1hoXva9hT7hiaWI0NnPobY2c8leZaAn4a6zd0.8VUYhNm01olIjFMTC5ey22.SeBglj8upP8RyfNs7MOE6BVvZvwawINdvG3smsL.UlWFZPGN_qWmTu5mgKJzfaeK7gjia5UVNIRsQrLdrY",mdrd: "3.GdXVT2o9X5jcNv6aFkz95XLUYwCo0CwQFXv8DgqdA-1739803638-1.2.1.1-Nkt28y8F7PI41xz0K2pDgsRRMAJKP2sLIY3SeeT9_bUzYb5zCFzaSMhWHny.dI7.q9C40kwkToSaMwR9rOu0pJPUYplP590I6LhM3HhAiNwZ1NuCOGIdDInYTH4Ek0b1reHA20_JQKcbS96PYrPPVFWOnOeZbCvWezA39QOQcBPX0xBoKFZhCBTPsRDpkfs24PsTBeMUvqGauZgIAgIVQ0loIEHQ6L4Q6OZZGTBvp29hD0X0hhX.z2BQCrqHx73xKn12Cw1JNbonmv3oj25ThmFYgNFMKWyMLZhnYdFEpxSagV5DZPdQm2L2NXLIJkq6XRNgGBUbNQSXeCXGxqATOLMvwmwvrthQ5WgwTPSskASWXniDUaAcQM31Ras.BVHhaAjxQXEDtv7bYpdJv5sahLrxw4OpKXJ19wqjGxhSnk5GBnFy.05KQ.QR39W.AzdRz.sc_Wb0Kdjoex5Pn41tTRsOC.kLTyOjmYO6kOuZYHPSQhnP.F0oyBjJhP6dP24dgbO19WJpuuoZP5xQ_M2EPWlLvRpAWgcIgcXNMouS.1ZKE.y6cx5edv0eRiPRmX1NZtqZGWVDKwhCU_ePPAoibFzb3HJyuXoJGMYPKK5QMF3l1uBYENeDVjl..Jck8NDFJ.gK0d_oxNDvLsjOYZqh3.S9n3VmMjR6GxRjZ7dalprKA9jSRWqMTwgTWCCV8MFtN16O9y8T1nAOiZVoGeKmy474dDoRgnlR0n7nFFQrIg81AAZDvM_bTvtN802aJjyvfO9m9vZGNa1ZwJoEQTTdA9RQvRh7VdpKQrDy0354INIkAocC9atSGTgfgre7kSRyu8HkbS_JCElcchphSE8WELBMqlUi9Ns8gGVQo1uYLiG02dSk23L9Ci4nObIt8CoiWXPTbBHnpnk3qnNpFtTkVrLGVQ9aqL3mnzemVRvNN.GL6Xw_Tjh0fFyvTEmswoqzDuUidlVM76jhnTjrh8uNAfcysc6XUAgI63VarWs.yrMffWXptzEHZdd6z6pD4lSPZtdco1qOTiWteGO1K4pDvsSYuXW290OmoO_azmiULuwkIUEb6dSmfohJqhYMPulM7HUJJR399ET48POYrEgeXqNMf0AVrlRSba8lo35GwPPb_W.FDxOM9uPuAYDdd8APOjCypk.R36SqY7rBOGXZH3gZIvnY85WPEg8o0enNATiLNwl7UKKq79JkAaal.yDGHNQpfPJc_d90Lr3q_.ovTdsijGVZGX33lHoTyE8jvQ8VVziH25X9FVC.JaeHUmNlIpiuxd.7a_7QHjwd.O_IUyyvmAqYHZYbStBAfLoZMr2Py.hw.btc8xfN4YL_uCzVEVyzT3cgEDBlx.y0p27RP98wF0q7XOp1dzgEb4ZZctcVTWxsg66swOyB8uc4hzZQEP8gOse.A8mLXLpwRhwbsur_Aseyb9VyZ1uh.uW8U9gfm4FKQxJqMpVY6nQOCaC7Bpy8wVNywONLogkMcdCLTS7loB4YKRp_g5VdTF_PR56wQV6urxZ4ej_pDswoR_AWmBWXL85B3.P9Ay7r.2eicXSvWTWv7uJFBAnDA5CTJSCM6gI9tp8Ibj8e7DSFq84Hd_AvI9s4aN33OOs1sOQbZhgAj01dxSE5oa65YqCJM2Xz1LnKutnkfY1Fq.fekOprjgcAYyvGhyKHyMerTAWP9JTZ8_BwEEnrZCRZQaQN8t5jkKD5pALoJmFYsdXwC_GQ7V62yfqj0BHKLKAQhPAQEhvhEfBq1SDuaM5NosQwA6bn71LarHCT0fIpPOdMveQNZeel2xpgcMqi_Lybk.6UMggS_vQ0Zg2pjBq0RyDKSLUZ6jHHcA5VVPKWpZd.6XRHtEkJNFDidPOuf_XoY1.XOCzJPVvVCL38m0b299.8FX8NAmvXSXlxcOJ0GoIYunc9isEmG89jwuzyfzzsUYXq2YLN_E1PAmSyVi4Ymq5STT4CCiEo3vnifLoOnQ2CaA31"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=91369266290e3dad';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/abstracts\/search?q=recommendation&__cf_chl_rt_tk=QZYN4kbKGJgIgeQEWxOtl.J_kh.hW2YbB5VaHPQ_wsk-1739803638-1.0.1.1-i_JRvsB8l4dCwyDR7Kzr9t9fbWFECpUMdkH3v82AjtM" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>