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: '9135db1f7c60fcf7',cH: 'dan2OCvMYDbpNULDjSMTsUArQpCD4qk1vdJY54a.Hu8-1739796131-1.2.1.1-wDxHE0O4ZOS7Q2lBJF_6NFUbMwesm1vqP7PKmFbFmVdmlfUifWjR_UaOCODAhwy7',cUPMDTk: "\/905\/json?__cf_chl_tk=4C3vh2UfR3dsUB1b4Iv.tYVGwlYc9CNFO0suuDODIIA-1739796131-1.0.1.1-SbQoR5KkPLMfHQDESnhkfRQW3cv55oe1KpqRuRh1uZg",cFPWv: 'b',cITimeS: '1739796131',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/905\/json?__cf_chl_f_tk=4C3vh2UfR3dsUB1b4Iv.tYVGwlYc9CNFO0suuDODIIA-1739796131-1.0.1.1-SbQoR5KkPLMfHQDESnhkfRQW3cv55oe1KpqRuRh1uZg",md: "vFhQglQ6ifetnOA_JIvTgYlCmxtbtY6YKvVCJ7gTVWA-1739796131-1.2.1.1-49kXYgIGeMQAMI7._9YDJhBpg9fgyUE0s8CkmB6doyAOlnA9I01P8hmOPaMpHl4y_x80uESQ3mLJiebpQlzovOygnji_sg4GM7Dpg8TvxP6c_CW6RbwmSzzvlwSKz_vU9UvULZJ8rYpfci6hPxCWNO8dRSLTcQX7l0lojMhuYCDRQoit6QFcLXCmcJKR1tH1mr8CHLS8u.Kd7vtzdC5C.kCfV8CzaAZ9zmBzK7u8ADw1k60C.8CmxgNk1o3FH8Gyq3uZI1WeSLTv1urvpiTYQ5CW2u4xfuwLBSZ2KzPAIxdU_prQ9XsqMk1PNc2LAZfahHG8RvxcJcBOD7wYIXtdHqQYontypL.XXEJT4CXiQ19A709UzIos77ASKUSk1Kd63380PYrBv9AkRz2ZAdNYWjyzkc3_K6ewmWweVmYLnO9S9rcsY8nWNr6Nc8Cd3EOFCozX57xFLlnoq7I54K2CVcx6KvWEbCy6892Wk.GG0JnsVzoIJEvwHzDyKI1uGHYYd9ELZv5sA1b6Y2mjukpbDv_o66G4DzIQ552CTiM1Exabhi_1td1lYRqZPH4mlCgMgCLHWcxNlnw1kl_GunKl.6TrU8ixWiovzHD8cx29c.2NYhXB.ljSvbem9aiGOj61Q5mGcTS5eWry0FRij.Tcf5G49QfjMshC7u7SfPTuEtwmvOry_eo3TnDzi7jo6pn3SbLZNxYl6VYF3Lle3QVME3ARByacLU938D29VLvTERsNS4P_TuBrXAyYHbTPHi9FZ6KVEoL0iP9X3iOqLLJ9.84647eIzim_XzeASWe2I7ok7I2R9J9myAMDx11vcrY8.9OwbhwT5vjSOD4UWfiAEpQ0xieMzzB6.qMAzF.oa909c2F6Dzyzzp1Xx1UiS_hNSITZjaa8HtbDQv.s.SqhwPLIcxhD49CpBV3BhhrauXtu3alROIrUcrMyq55tXzm5l.v0cO.7IYfAwvnluFEkp1k2ZnHyB1RurDWcbiIf0DxFB1dwBNiG1OSzWGMcctPhbwIctiBXudjufLe56maj8Q3IuexWQNc3faURH.7KUjBIRtzCP32XowVDJPWUE20ocOx4IZi4pUhDnQoKA1lZu5hmo6gb7ViLjxD7fm.pUruVo4mZuCWaUJbQWGIGHZaWRnsNdAfJbWtAZIUVz_aa55DPitIglaQ2FmQQe4HhEtHojSeGsmAmmHCWn7nV6.S8ut7vMLkViAml1n1i.Ca.b1_wrfb1BEZkHmGt.LpKf6QbrYghCBDOdO4dWviPzSf_umLhYEsi7CnSe6ttgNeIut1YkPdsOPdec7lrKANIdZDHtiUHPo2ZryBIiOqFvCkVQXSnvJgOBFzULC5VAlmvErMhVSp0BpSVbF2DeTfzMWtaRMz8WfStm7lnn9s_SmywPiYbwvNMSC98Q8EoYE3YtrjrvsFKsaWORnjS9FwfcXczwvSvixbWiDKGPzCa52IZ1mtSBpdTHdFi1teLIBeHC5gX42qWrMD130Y8e.thbGpNYEVF5q4P9OYOnth10OLSj9ytpg0jhG4mKbV4Ln_Lbsn5UKPgKCH4Tj9eZQiGIAy3FzAN7eIOT6LeA3Vof_TSVvY_fpmTuVrno8jz_KEv0fGiQKnUY_5BZMZCy80KIQ.K6rxVbngvHH6N182o7_5FPIDJ3UklCpG6LKPxwWXFJd2G_dxnWMk3J6zc.SVB32Rl.5ivEHJKemn..Ua6KH0OyQzTVli2ZgW_9trivaTnKhBZ5Fqgxc7a1pQD5YLtv5XoQWQOdTW1KBy6bGGeA1azIDTGpeCnJaQFFK5qatN7VZRlFaIJJ.fzoulOSo6LKbkLwTL7_i4GIJW89DiYYorK2AnFAtRMMSN7hoUSI60JBg",mdrd: "v0YM9oNaBJcOIYpXUcfiLJHJOYI.GFuA9xzigeQ6OlM-1739796131-1.2.1.1-JXa3lklz5p7p9ipqoRFC9hoKiaKfontDYLYMBUd9BdZZSQcxFwPG77WRETM2h0KRPleQoCoYZwel0Siyds86K_BWyp9QKCX0piXAlkfSY6fZI6xEhImZsOXjkRp_AZYfskgccAMGQQ1nzVCfFVlHqzUO_Imxc.1m_aV3wGvddhKXsOljrYA__zlen28tB6deWFL55B945GK9ksnLzwBmmkYkkDbpOSEA0TsJJY1GnMWcR7yEFeck6huO8S_5629SzOS8CDUeEyc8H68wNbGnJ5965vijca7jd.NvACFOr6jrda8T7a6iwJo3JtfpEXNXbnUOdOYT4pqIbWFd_AKPgfWPtweNZBqiarM6w_Kzn1xNuag8EUDEBAPLtMceVuWrmG1M0P3GJgj3DUy32KZOjcVEXOT1yPfpkA8uU_BhnO8_ebj3yX4WWteyLEN.nSfZ4SIy.VwwQi3wRW_lPcgneM0.A2Xa33jOwbqGWD7aL8EkfXUfeKxVdSm0QL3Zgcz.n6QTKflC4q1aS0ozEXx1432c7oYd1NE2t7ICyYe.FXFHuQOrxeF3hkFbHWdYg.xhdqa66iz13NGbiTWFVvlT301GC.yEzq5gGGBeTq.PHevuPIHns44XzY.8a4Is628BhQ.CdUoG36xi3rvoipga0eKUxK3e8IJVmvEKLmwLUpY8nZdYB0leuKrJjpW0O4x.dBV5PItxlwWcy2cJbfjpsEVvRCBtQvV9UfH5ImisHSIxhHaGf1ljeSLk816EmBdwZlxsUYeZfDzoyJ.Y5ZkYMUpDqlSsjAxGlr78kPxPeGVoFukH5j_kG8qVZghYjqSEpNieElk.MbfePo.aEC8Yam7_ou4v6laD1wZMoT7TqXAqPb7uX_ToO85lGRpLEQT9nulHF_aNPUdR1Xs5.2SAt4aHvGjPEr4xAjNhD_ERo1AITjiL.dNZbBw5tFUftaiNL0xagBfppqbC2QRY3pm0LSPN3JTR5aor7BEycTKXwAIFrkdt7zgk5BsKp.PIoBqnkDoKs9OLCuWUq_s73URYzhDA51ZyqW.5v74s8edSxTTJM5AFNGzwP0qhzjocx.Az_0nW7brcIw_G_M7FEFKdzHhBHCA0dHEujK3Tku0vPjzv79LopqiTJnNYE6Nibr0IUXcygCGEARx1HL8oNJDBIIyYiokdsEcHD7VpIxUDnuuCeI83pLgUTe9KZv1PY7HZp0KzCTd2Xhi07D2B6vmrYuiWwvU7iTofoUFwIzmo_EgBpjzzT0cXpkSoOoChl6oS50geH_WRIQx8FJHjCdiK7tT9EMIUOOyQGELgVAoKEvv5ZHVhDhp_eRYrZX9ZzggyRAts45TVh3MPke_u7gGgdJ3aht8RRFA_idiZegsUNT2IeEwWqWFKcpJKWl.M8Czsd_Ku.CWpxPLdpKxDrk5mnIE79ptineGzLCjvm_dp8myHtolzeM2QFIjvbLzOBrKuKnwIs6MSyptXbLBICYNeRH2XtWCgFu94FZU9qdvso0Dxh1L.PmnynqDWyQ07aZWYdTammwyMsilSW2xMrEgLNON5dtnccv8hy5cSfANawrOA1zy_Fqup3zFe79y1siHqYr.GOlF0VH4iS0mhrsV.Tuk5XQC6nU.ZpYbU5fJSvOtSWnDUFDGBOvSFbnRJKJMi8dNZmdehs2DBCBRkaiZnO2n.XZ2ds5k0i7xXVc9qmQgjey6h0D.JDxKEVf_9qL6LZZzX4NgiErD6zAhiwE3h3tCBw3BMldKXk16jjVzlc81zbxF0cRYMLrxNjcH23Oa4lINDkRG0Eq8bPefPCCaC5IAupef7TFnSLKYBUA2QEvvhspjYm.Cx55iocH4QG3SL.pu2MJogPAfsfEsGK6XVNs7rjEBTMwKe8iGLUR3YSGl4jp0k8mzaqH5MGEvTaYaOLtEm_uoebz1_woz7C04eSi5hSNQA9vSue1k9oJEiG_x0p64tdqXmrxaChO9qXX2pKWs9ne8r0UKARGU6Dz3Obg"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9135db1f7c60fcf7';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, "\/905\/json?__cf_chl_rt_tk=4C3vh2UfR3dsUB1b4Iv.tYVGwlYc9CNFO0suuDODIIA-1739796131-1.0.1.1-SbQoR5KkPLMfHQDESnhkfRQW3cv55oe1KpqRuRh1uZg" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>