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: '9134a457dffe3e2a',cH: 'BZai_UjeUrUz9a3SnVEhytwuQ3jErwvt99cckbTUclw-1739783402-1.2.1.1-LOvBg_ivQo5C1Z_.gB3MhuAZyIYtrPs.hukaHL1NIaaomRTuoK8wbCff6BYd37X3',cUPMDTk: "\/10012875\/apa?__cf_chl_tk=h3V20vLGuur1To8z3axZFiMJOiekL2o94BSOdBJ_sEA-1739783402-1.0.1.1-_U5JxDj6UPL8vzmlxnFz7mm_emC5X.bA0aoIx6rtcpA",cFPWv: 'b',cITimeS: '1739783402',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/10012875\/apa?__cf_chl_f_tk=h3V20vLGuur1To8z3axZFiMJOiekL2o94BSOdBJ_sEA-1739783402-1.0.1.1-_U5JxDj6UPL8vzmlxnFz7mm_emC5X.bA0aoIx6rtcpA",md: "Pb56jzzc2mSfdTsfOA26mSE9qCl1gNLPF.ibj4h89jQ-1739783402-1.2.1.1-pcBQ6XPp687vQ_9s8m.9OG6gau6IugmK0PaPP4.4OQ_AyWNZ7Ca3gy19PTGEHLBsDTg9GZM2P20nEqtE69_heUAdwjIMEr7F7A_13N9qLmpTxXKpQmrmdDRL1t35hkR2jUVE0GHWDS0yNTonhKwIi_O9ZyoPJuh.WZxM3NouYqvEh1CJbFdN1ekgfm7mMGfSBECKIpkFB3mTmLYa2S9XhK4ShgJqNgQeSjnBExQUlMaHwRt0dP4EXGS0BL41mbmsTaYONK3wLc2lx3UBDEK5x2hHmB_NtU2jCy5tMGBNgZSMCCYUy81ddnRK7WBEdpcElDIOw8yk1eRTl31Pqb2rW0pGhlFz04rKsPk0EM94oQH.DZdSsmS4jouCJ9oYU6rsQeA5GJDBnZyOt0rHGwkMyL.54cAnA0SjQd9HG42fUOviqtgE.wurjS.2SmlOZy2a4YmzEZ294CF.JR23bde_p.57h2nlrJgLzeZjEvQnEZDsL04fd.jrVngCZkaOCrDJWtHcmCEl3Zjl_3WarzN3WXfHw3Qm5B4Plb0zT3kqYJ1NKzaBjKXmwdd5wC63QiGstyKMuP0Ef9HDc3CTzL.oMBIj8LJ0UHMPQqcZ4n4_gStWj1RQj6QNKp2WE3X57lpFS0dYyOFsuLJepS00MqnK4nB9rnsI3SR4ySaSrZd3ti_d9jkqQsgqMZQpcEgVH5X47_oDIAcgEZcSoflz0xUhOq1oWPsI2qYPbfZjRheOKrKBJuz_JQlV7IStT.5CqwbuCvzXT7.c9EfQPp82M0OESOkv_IC6bzx_EIZuUXntJqHh.iLGGXMvBQTbhoWvVKpX1BfGRZZQ42YHsHM4Cu.z01FKLOVyTTB0eZ3BQRFxMuUBSdk7aeSrd5aVlN6dtdlKLmlc060mz5GhTjxPftfnsLwUF_DfoALi6ZkxAIZ41vFKddeyYxoPBSdyAuz7lbqgr.ynwWzW6_XJctMtPHDTMwvgnsL8spMSUDuCKShrjPwfLiRBfAplifTb01MCezMEHr7GVPdyqRgOVmKRW2hXpOh8dAcuYMZqnmxyGCbvu16hpp0.0DsKxx4sbmkcOCa3G2AhK6.oV.kT037U7VNN2sM69THqC7wSUyu08RDiR5vnYj36LwPjcQut3qpz55lyhINutV7mwFghI5y3_V_vEOx7U0PjnIVUeMSMc7vBq3KWyN1Ubd6OCsLtadgNlxqxTqPOX1e_sflfCd0T21pyNu8J1y5NfqM4vROVDUGWrLPcjH.jQUHEytfyQrCPjaQZtTdLWUbQVgNUF6DmNwWaDJaXOJPtpdxXPsncZvVfw0OCd6YiT3K7W1yf6aOJjY1tm4GpLVr900FnUrQsc3qwnXjg4hZm7wJk560FySC3V7_sQ42Lt.kb0L8BZFve4xj9s3c1__t9RhvSQ1VkhmOPJJ9DqoOjLcZEGwxe8rC8BU0mB06tQ3YDoaakZUNROD9fJt4JfCnGgeGCYjZPqRGuvnWKzHpfn.HI9qGLyBcFpWmsNX.ge.D.oFtR.Fynii1Y5famjDYU2_GJTEgdSH3f_zG_Y97KvE_olubZ2BcoUQBLmxEKKCh0A0lqwPDStibVTOpf_8D6rrJDnB25e1bQhoAnquEtSc0jyc7sbddpynO9gdoYGpmAgeFpcBp4pQsocFyHf_7CSKaDRaUPzvuF6yFmPDoLbhEWQvJVocNvmQM7_ykSsaZxt10cWbpT.5qGG3qENiA6gwWXRhwbhMCOhQsWUb.cxF6U0gcQ3tWvcc1wkNbDYZdqSqznYiYiA7ol9Rii21zt9zQ7BFILfuimg5WCvETIc2wSf81i7oiqElAvxcyUj.zL3LbC2UhSiuhHaJ87yENaF73sqNbBOJQodL77_dab.sC6D8Hvxdc7XMA",mdrd: "GgUWlQC8f5y2UpRaki.vJD4LIuMr2m.1BX_hcj3.oog-1739783402-1.2.1.1-MSgXfx877L53qGTBTbeVFcv4n_5rGgagge5zS326QoL1WTRHeijKqVbvr6fMyYy7KXYEeI1b86PjlRnpQDFbdEsV6bTEuQRKYGUi6jm8yveB9Gf1Qbqrql9dpjAisUhbzXGw4JGyFiz.D3BU2c57HRhWuFmbnZympgr_cswlcn0BGhLO8jiimiKXoLp7pZkdPIjsNY1icrHLSfardowevIfrWO2BH5xuunvqIdiVAID.LLGPIpWoLkvHDcrNR7TD.M76mS5juXpaki6zSqtJrajdgh93o5udk.8nohmGLJw3MsrDP9nZwRMwQPlDqcSof72MJCwYeJCG8hWHrk65VPvCraIllDLPuSDAub_U.AT11AS9sLbP4kDW7kGPnXwQ9dizXzStsKWTzbjMnpObDH5mUwqfKdEO8x2.tSV5TFJFF6NkeXZMpOje_MYLxZiUhuCxNwJ.zgLqs2XDr8WFQs0XdbTMpS9AVcKsQ9Jsl5f.ApwPFVG97IgPeDLrSW_kBYxBoi99NA.OlPzM3VJX3WQ6fjGuUiY.k0vgpbg6MCexlN44Chv6f6r6vULUh0ZBzJdvchyuvHBd5wRU9XSf7aRfA0mh2xRrLmeqADO4nfPVHTrecGUqf.NZynbMjDlhm_JnFXcHc4bCoSES8FQw8eATwMsCMcKn_hzyaAbM1azFS_ME0OWCB7NtTmDRfrWsLmzQJ5_iVEbrPoTxKqSAYUHLHTwHpNScc.ypcxUBMtKBUP0z0tv3Fik6fQRzG0KcfKq9YoSYAhv5g0csCNcQ_5LQ0gilL83unV95PvX8nFR1ERSM6OOS6Ig3hrmlfb8bcxYcUCDnIv1MGeTjitAjewvJNAXjOc7dVKNHn3Sb0OPkCj2f6ipjxQxtTG3cfFzfpJgaRs6ui4JPQK7alvF_X6Ek21LzYoNa9OylpdtsQ.DguHJWD9S4dIBzhNtA3KpSgjS6hxW6eSsGJUO9UE4sBiPwX7FJy8ZtjEJ3qSuLEEyn6Th8Vp6wJi7nTGwqP7EaEpZ9iMKmG6HCVpSd508yFK3Ux5ByGAhDJnq0P4mfEK2RjygUYqESTuFA8809DaTTJp7xZPLsDbuCOCIy9Ym6DELdvGaU0UuKTF8pQOz2yj_AflHpWoAdBxUaHXi3cAoFmHlZASN7TaoAPeeIudB6EdUjs_XOSACvWoUjTwok8JaRSIGOGmrCVbSShh4kZfmh5hR0Vt.264adEyQwvzXGsbkfCaaDUuk43LVu5HeSD70nhRao08B6JQ.XVDDG9G35Bjy7I0K2lLIQWHyK_5ritWE.CWN8M7hYci.1jRTj9AjpjZeCKzMwW.ZTeV9iEjz06OZxg3LBsCzH6CqjmogF9fSA6ligEt_CF_0aQ4.IjrDChsyv9DfgxUYQ5u29bRYfoSsZC1YfUqvq0yctTYnWniJ8eHwNlSdEw1VNNmwVJXxjGjlTtBSvnrzUbDj0XgAOeoP7q7ly6xc11koTnDhnxEL3WwE6ROn3WitzToYh_EfpWGOe2d1gd5yqbMvCiUCjbcRYAMiT8ePG0U_aQ_c0nFM9M94DCS5AMqYpxWj748A3HlT9BsdAEQ7GddErrcB5M8dN0xasKymOvv8ATqr_YT0V9wZNUX3Phj1FkbojeYnnEzrHcVvqYFFVPE4cXzLZVx9sKHOnVAhgreW2f6F7K5Nt52FZlmRHPsf69mLG55CeknhwzY05OI9jwxnsVem.cwm7Pg_zdyX7SIiu5vBb.XimKJVF_Bo97C4NStVcTl8_Fgv4m8Fl3A9PY_SMBI64CHZj1azOZYHd1nYTm6sYenKBT_2jpCOopQ3BkaiIyilfcclCw8y5H0yWtWhDqCGR4EADJ7aL7OfjESfpW8k5uzjLys84nD1dPSZUeplMh7aIgVq5MqA2Oy60zU9Zph1eltv1iqK7GzCbLd3vx.xst8GBT8OBX7UdnekfM3VKX0XiHw4G56Nz7.IKMqwlIhcC"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9134a457dffe3e2a';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, "\/10012875\/apa?__cf_chl_rt_tk=h3V20vLGuur1To8z3axZFiMJOiekL2o94BSOdBJ_sEA-1739783402-1.0.1.1-_U5JxDj6UPL8vzmlxnFz7mm_emC5X.bA0aoIx6rtcpA" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>