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: '913551d2cea14422',cH: 'qm4Pz_nm5jzi54_HAmxjIbC54g5E4DWU6DQe0nULimM-1739790507-1.2.1.1-ZjCB5GhubCLytPxwLjtjbixON4cdKVdxE_6H7UfBdcbnofCSevWfAzOeC.TEa0fP',cUPMDTk: "\/1335\/xml?__cf_chl_tk=YUGk8KtZ19eZAHrY9LpKllVbzAUyFFzjYOYlHGfhHqM-1739790507-1.0.1.1-IUU2j1vJd0QTu3OatLCwiPIE0Bttg3U.8e7M7xkJmxE",cFPWv: 'b',cITimeS: '1739790507',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/1335\/xml?__cf_chl_f_tk=YUGk8KtZ19eZAHrY9LpKllVbzAUyFFzjYOYlHGfhHqM-1739790507-1.0.1.1-IUU2j1vJd0QTu3OatLCwiPIE0Bttg3U.8e7M7xkJmxE",md: "WyNd3gNt25QxozO23uBW9V33QCiXtKYeqszQBadHcic-1739790507-1.2.1.1-IIi2U1_8X9vxDair7BsDak.Mi5vDmJqeBP5PfBqBM_ZVBHvSXDW.AiqYcG_zSHqKZpoQWGkPvFx9ezkj9whLgUAeK7AEhzEMQbfZuS.dwr_Bqy31yLkknnqIyVKm0SUgUUMDOaRFpradlQcqxuTcuaTag1VWBgARLzq1.RDHLahSew.LX7.j1kcO4lhpMAN3hnR46ZxAd9829__yKD1sRSR57.xkadoeuxL5Q2_mcjfGBR.qv_gK7O0er7foicJk_Hlos_CjDK6wFA3Tm7f1lTFKubOKyY7yI23e_rRx0x4t3QyXioyX47wFrlfPoxTdF3dH67kPHW1sQ1zQgyTRMptf2aik_lxRoFT4ii6nWNPe1XB.y2q88dhLE.GlV5VHiSiaTL.ZRXS0fgfg3Zo.4X8IRFBYqmR2vHzvvBAxUfQMpiM_H1_1q31HMWEwI.ZOXE.q5H1h.yswtqWMlhE6LlgwHYnOOdy2HJ8T8.XsGTPQ0c8MAA1uXVWSMqwkOFY3sRs11U_junNgd1DoReeduxZ4Iu.xtyo0NiIiXy_T_.EBGEyrog4LrA6Rpz7.WrL7FV7WcN42z7ejFyUcvbo6m4IzG0.mqBG5VU0.ZSR2zRrFJVUgtcU4r8eEsQCoy42jYei48UDqRhsjZvoAAEbFKnGOCBrxLLIhzLoKMUBb0NrQ3i3TuxTeUPfp4XdOKHpczp.EPfZjEDCqBQghooTy7aGHjdjqooZ0U4lF4Hy_r71Crdwgck9SnCIPNSfSpMqXR6sczEBWUTLMQVkPQ2W6Mqal_FydVrQF1krtxxG9IaLnz_.HA0WNBZrdX96D8nenPDktIEm99VRdWww2GQlxCgwbkQBMYGz19QWwoYOEdWz80_QJzhNglOOVuJm1tz5C81HcnmedlJG8r2ev4K1kn8ZEoPNgYyYFO87rEgSCYP5VD9s_vcUcc.jfspiPqd8_C85YSLlmUX8ViGB7f7r_e69XLXdfIQuLyotovGQpgLLwyOcFb2Y9cH1aTBWJy1jUsdgD0Be9icPdXqNrO8ebdSF5t1WbfOCWY6XeuczCptRgNUAEYGhW2Mt.Av.KTpmX1MWJpqbeyqEY5Vcboh5wku7M4WYUa.pATlhZqEYVMQhj.0HZ.nqV3EolWLz44UNseaAuLm6FFAOT7BtmvrHqhwj941Yg1EdMS9gBEgT7IAVRIQNcSZpkLN9xfK2.jWWOPECo8uPo.YC7cGf3c3Du6tvL8yYIbpJyruTGUpJM3ubvY55EhS_TB41lvoXq9cr3RB1S8IoNuMX4tVr_9BdSPO1LgV8tj66umyRRRHMvlIyQDTtqLvwjHrh6Dc8DHVfgISmB68N.I3e1PDzwzqiSpfGG6r71odNj4k_UOGm58VLymuZOeh43SFXY_tWNdelsRrsDu6EmgXDnapZna57XOVUAgd3cvj0wpPbscEyEFomDU_YgW1XSGPnQCO4zwdeFYDev6TF0shPZ4u7lIJ5vTJKpcPVwK4Q99aeuXSGfKf0sfEHSla0.zJKoxcbkQIx_HoNHNFrcO90.L2TN8gEeV6mRbLxKeglxc_oGJmhCqcT4d5Y7sVNiWb_Jiq.Z4GgItqur36k0tqIad6S5b_jETUxoa7IsY12Q_b1KbP682SN9P9VGPfxk5novQ7a_eN5O9boE4HAOWtmP0FKqxTGVXaxhDInpOXucueg80VjiyXraPNA6xhbfyyfG.At6CkYpIO3dW86Vr0dqI.98ztlcaf63g9CH6N302gM8erpHTnqlI6XOe4aD1detGzf9AQ45Qa1sIKj1hpWyI1MJo7LHpSPhkP2ZV_COGf.j3Nhmw.ktipDW56oLa1xt6eXMzNqm7ih7Fc5VP3sioO1UawPTug",mdrd: "wCrRLXPHxiURnUxLOkf9m8LEpNXFqFgccyOQAC8Xvxk-1739790507-1.2.1.1-IbxZbZGy_uw7w04eHy_DiWXSBeMkVw97aTy35PkSbpEsfbuzX_EWRx4kWWT08JVRqiqDigTQ735ChLeFFbkH3Ruh1Q95pT1j0zsFQDRIzQHePl6zEGznaSMgpuA4WwadWcVbG12zbXW6WDrguYpC_vwd3ap_uMQYRWLn8OLCoY_2BSxzv_5MxzNqJ6z0KMo0SXhOEfi9euFYh7uhO67s4wdXC6H_kePJ6jcT61lWd3bNCwFShLfxWv.k89DFAziQyYNbjHUJl93me3VNEadhIquBRs7aB.lNQSsOJf6LBQbOcLs1TICMqOlfBUxun2aalDYBEo5Ibt2CywXhB4cnbWm9rCvui.JvUUb0vVbgfHmE.x2b7r2_ZsrvQL1WMCaMwuQjnB9VkPrYq4SsujKbWMgHV4ih5FvR5UNBEVriIilB5_bGHqDJo6KHDZLIvFoelDl0axWBMKUuA049__AP4q8WBipr3fij0j3fkA2maOxUzFGW7ioKIv6rL104C7qfibI8dv1xL9.1e08XgDrVEVhZzehhZHL1LFp5T15x9Svfx7ff53JgAG8.KcaLUUmhZZ8fr1CaEvat7AZrp33SOsElE33mkf1vVSpup7m0HCPl2rYHpIkUqKjmv7O.FOd0_3UZLAoUEkDcIWuT.XOWlSVJMINs5E2tVPcE6wQzr7dN34.am3MfRzcvOreBCv3F_NVQhJbU9x8tOyhetO4c49Ev0S2zNaVTiFxINJmGzovSTfgiG7oRzIGu8foO1lOwgfHBCgmvvJdKvh86We2iYSclcth9ODLtQga2zpbyK7BpmlK4iwpJCWY77n1DmFhePiF1ExqkJBoOE1xI.km.hlIwa6CW.b037qK7NU6Ts9ea3OA3iORezWYXgBUkTxyU.VDgAOjDaijVnq41FeEpl0r53MnoiZvHPU6uoIBk6OoXj0PDSdk1Jx864KOMus7BGsNkM2oWIIfBYT9No0RX59A_.QasI17GLnlAgJA0mKyIgNOAHsgjazizNDcWSq8q9dqdtJko2vgvwMyUy1gymX7zwTut3yBdvgGLB.npThlMhZFVH2iePTklsHQwE7924PeYUCAfr5Wthse9wlw63mRpxxO9JiCoaEkbN_6cqY32NYsy4My5vbIq8_xNFpIwkCa6ZUC1D2pnmuCoekNLEdy4bIG_OLJhRBAT7SXO0Bp6V6PtWJoqH7uEJwzC0NAcn6CLa_htNOLYpjLp8OzxzpsUunbOupjF5JYcYsbg1ZZjzMbUGW.OW39xb5GYqw2W1YGUwvBV7J.6wqDVDBM_VTRLzXwbyRo.c2gxMdkkPO5jSjpDcV_57YRxhVWenhPLzM0J7CuDuC6Ys0Xuqo6SVmqiLvK.frCPoc1.qxWwXbTe94xW.ytFTVTOOKbtu0uVMSZcUWFzZwVO0QgQ4MDrPzWgW8VtnqNKT9QAUiisoh0UKM52iCkKGhdPTBXG1_9iyNxPWgwd2Mip9C0eGA5GH_M1YPIb.i0I4jx6THM4_j.H0kEm7FITfsaax_FpJBIKDGy0LSZTpHEnPAKd5rQEqhSvKNhHhy27CiD4zO4APCVc.wWvjbxo1ZPMq609Vo2YkqgS..T6hC2mDhPev9FsAfejQ4MJ1y0Ft0LV81QtYaqQNhombEwDS6qrGEj4Hzn7wtTLlxj8EtZsnlxjvolol8SoTKRM09jlsfpJP.fuNnKxoCTWytpA9LlNa6bCe36SWJgj0eENTN6JgAemSyBjFjlhbc0_shhiWi8Lv0bl_IinGXGwu5sP6WgzBa2dHo10odrsX0addJQczHpvZ4n4HdQSmfmeuKsu_fXobs9yXrkZpcH8_mYHDbojyhthhuFs0FDIc3W0y7kxbnMvMKI3YGOKLdaWHu5342ph4s_92XJDmrfi7R6OXtvy1BbKMO88W.TX.mZKi3YsE4B8sViWuPN2xJimnE1xzTGpq4J3rm9PezH3BqnyNK5JxCH0I3W6ER8VmdUhyihFecqxHT3bYg"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=913551d2cea14422';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, "\/1335\/xml?__cf_chl_rt_tk=YUGk8KtZ19eZAHrY9LpKllVbzAUyFFzjYOYlHGfhHqM-1739790507-1.0.1.1-IUU2j1vJd0QTu3OatLCwiPIE0Bttg3U.8e7M7xkJmxE" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>