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: '913673a59b773fac',cH: 'uVFyGeP36l2xqqDPI.VQULBmKoM3Auw_M78I_HxjCDM-1739802379-1.2.1.1-cQrNJBkXPv5JxyK.HWdlb78dgF5ZWkQvxCgHpFLNuvGq.nJmnqlMo3u71GTJdGpI',cUPMDTk: "\/10010676\/iso690?__cf_chl_tk=UI5r8VcNl8_BxMIHLuWs_HEtQ4KiwTaai3Y1Zf5c9Nc-1739802379-1.0.1.1-fE1NWafn7KQXSuqfT4Nr_Eo9EKmrn3oCk8Tei4xME14",cFPWv: 'g',cITimeS: '1739802379',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/10010676\/iso690?__cf_chl_f_tk=UI5r8VcNl8_BxMIHLuWs_HEtQ4KiwTaai3Y1Zf5c9Nc-1739802379-1.0.1.1-fE1NWafn7KQXSuqfT4Nr_Eo9EKmrn3oCk8Tei4xME14",md: "8yilihp9d1Q7RfrJ2IvpWMAaalWuUotKWI_6B7WudZ4-1739802379-1.2.1.1-c2Fms6uypLjm3FaSEy.dGKmT_sh1gFdib4PQDzG7aQqlLuJzXDdtlLLCfqxANqmFW4t9D.Teb1AiapR0s6sGzCKDh8ujTBEVC4kExpUkcFHHU3Ai2jQmdNdYz8g72cSRrMe3Q8Tgrnm.rYufH2j5dzLwJOqwUxeO2zvjXi1TbchKODi_hvkwNxHnOpzjwlvNi_9qrhb3TaloLgypEx.HhXVXMx7CR3DisMHWBL6DNbZurWWzloKvXOs3MzjKXoY0lf28NB8D_4M3jPik2tOrjnpvKON7rnE6HTbIJDTltWdlmv1syZKlKaAjiJMHrZusgsSpImAjNTn66wThCUWuCluvC4FjiazQ0cUHR88YCcfa5hydTP9EWBDKhmN6_a0dUOPWNvzoAegu756Ti47pwnlXwo5EOV.l_SLrIi7_9cfsd7vRcRnAloXO4LbK8Y_VlQcN4Sae4kZ444TYpC0xRaZv5GTeHxWjQ.9cXufXitb_HyehzR9IPDvXWGy3pfBPZs1wXSWW9hfL_aoNut26g5ArDxZQIufjxALE01nd58NO3na2XcBkQ_Xn5dvXvXMhOdFwwhnEDkGxA_QQe1HTrGuiQvlKYX2Vh42OOkcllFXcUyzQf5iaHQxaFkJrjD_a3gG_En_nXiFq9g8EgMXST2AknR2oWbdRNYxU75JjmPf8Qb29tjb9s8lYSTZQcozJYNSjEviBQJ9iVSYucXGlvwSBKHzkbEdr1FTu5IcP8wxgVXOfA3KQiashTNPc8H3c4KBZR57HCMcEtkQRDLUojf4uG4BN3lIkOg3bcKTBS65wP8Ef0D9BERPeGUhaNbwvq.A65Q30TvyorsoGoHGPJokPYms18ZOLFWUf.cOKJJp2R48dMM.OLKPy5eLme6WHmNySB.5LgrS1Orkl8CMcp97p_lo_GRx5EKxfJNngnZVOu5luCPrJm2muufO.bQVzUD3YkgfewhUncQ76VOt9IebpPgTO.3LKvIwl6Z4d7qpYcuT4AKw2_vmWCYU3GLYtQlF6EgpRUJceBJJuiDSPAAMrnBtQ.kU.cJmqcMA.VHyvCh.lsfAhgHPu2_vv8i1zck4OR0jHwW4VpHREBxZ87mSgRZsgHraTDldaeEi3QBcnNr5fX7RtptwSoNcq99fsNVWT0yeuYjXpcoz4scEflBdwsfbQ3SvDOu3NmOl16FXZI8ij_DOv6v76XL4MT7tRUwBu7IC5Mt_.zRaH7I_216Kt7B9j6HUzsmi6dDfTrECSqOIOnHDBNz8TDYyAijlpxihh1irTPJkLVz7ESWMmwYnRMdvvQWf1AbahJbWTYiR9w_tnn4HNvFs19w3Jvag19oNIsw9MtujYHaorofVXIC35ypFmCN.T7dLazvFYfZueg34sgnP5iwmEythA3wfUIA.WZTFlgyVAWkdJrpIE6QIv9AUcwVck1u.dGsvAsDZy410XQnp4md7BkT0IAS5809p6Dfx4mg0s9U1hny0gj2XH2nxkkv0kyUYVBa.El.lnKoQKYRENhjoXw.KJWUFTItj.5ctjtc81JLMQC3nHFv6oK9lTOhbeNGc0NVqKJCSLJnOgJH.SFF8tuFJz7EflextWVKxmYIavtD5l4U0Gfjps4VvkYR7jfN2MEKX0vkH_ezVYrgCiYMhUBD28csdpi7mMzGe4MG9WDYX.6XPKbxhhyJcaKTW4YrInFkS.UvREBD2ptzHet1mHPCWiA2sGj_PwqQKL8xHL_gnK0SIL0nNGmEb9s_vgWHGQp70TuRf8HqtsVzDAmkiTpYSpT5iGqosLwbmz8xNt9JF7.wdbuDS8gZWHOdTqK1VDQ7_zMoceaNjiI_DAJTOriZF.od1Teat3tUzhqmmRV_VzY.CtfAy0MgypJ6SpMOmLj_dYQr0",mdrd: "5azoDaWd.n_OQuUPiGoAlmyZ5gSHiirWOlkaiwv30oE-1739802379-1.2.1.1-K93mokgX5vnAa9gbw5bS_BGfD4etaCtXNJfoRGwyf3_MeJ82_iKHxkudsd4BmIvQzwSiJUmJ5pPmKGizEwTsE4gYK_Oy9kwbaBc6CVEprqghSF_635SaNIE1tuoUuMv8GaJOMAXBHQX3gLAkzWl082Dz6RCxQYwooY.yMgInhm.eb7Joxhab2lKm0y3usfO37wiU519BvWruc8R5ncvozSOyB4Bn1FF0g1wzRdentqHYOKdajf7bNqJQYLCrF696okD5M0Vzq.4etga9JVmwCVvJE1k2GwJjEovK3BCsYAVg13wJ46qLMiahkZgl8xZ4xRujhfFJMxIudGA5O7.os5QkRTv2S743rmIeXmbcw1JaeeSDux_wD079IVJA5sWdCn7DpuC_Nsa.2pWWHKJRG31z2twpw7eFkSMcZMheqaqO9ke_s_5ZOfvOdbXCQlIYqVr0I7a_DjtQ_Tg54YGdemfRmfVuwEHRKrohE.bYDANhA64Eqw_PbUDXZfBMpd8iDNGJDNhcU6C3loo9Tuo007umZDEkzJSHaFAlYHW.eoaQfhPta1qEqz1YaReGppT8lwWc.1K3LLPB11uNAzd.1UQBmMKYmOoTxKRZOKDp2fm_0vflC5.7nBXBr7nEHg25GzoLXh_eFZh7yrtpxcsCeeMN1IzLl7JBV8lk2urw09a0bVx_uGmEXlumKPbOq0Fqt8O8A5.umeq.w9dlF7XJcwoOtQZACelYCMB6BoWHjWkZDSkRC7ToFn1JXQUhWhOP8unjiP_qA2LAFeV3Eg9ZNr6nReTAjFioQDtdCI64GJnmcY_U9BIWQ2vsRR_xgTa9zZlMNLrOacKnQN5B0TNwvKYDJfyWYtAGlG4YdcgQqiEvqKJP47OLLykoVpeA2p8hAYGybtvUGL8twUB8LeNOHnnDm8bQ2fpSBZVpkj6sHOR71zj5_tSi_.r7zkpmArWd0aGAkNi_Z8yGDjEpInL3S0QFF_EgZ1QxshBPDVXor.2RoDU3GtMAGv2SzeSbHFAHM3ZgkvtamNLlaE7sYBk3OjXnNOHz4ExQIN1UIKdk8RSrV9Rv_8ZSHeSn8.N2if_q4DTpiBHdeFAO5X1VqsdM5FMinxuNyODPHte_GBqp0dZaa4QkgyXJWgoM7kEX80nQtr9Jb0OYXI2RA2TIBpoQZcqIfwc7CDy.NEx_cSQOZ6NKAeJPANCFkwTkEFDhJOC_EBPZcFkHsY8MawpFsutkXhyCnbfMbgMuOgmC27kI5.yFxwpdRHSsBTRzjDPYO9QKvN7Z11E2WdbTj_aqgySOMiqeXmXVs2LmuTJ1jGrzP5jsqesaSHuzBYnCi08lTFh2ZEI7PLLIE8C2OcbYZSf4jYflyCaCVSEDnJ5Gv.lDoU4CWUUrg_BeQJbLmJi.SnLIhR0nwkIu_OJ40v1wgQEPhyDEZeIsTcNQoAqeLIeHx2k_qG8pVBtQJY0SeRxuQ0t0ifU8KI8bn3VT4UFLNFtBOhKbwThTy7LcodizLt8SJyYUnPbAHUgiJqheSExBVMSe63HpsbCDLwyw8ckkO5uZbsKZ2v6IBhLpLOIrYFXOhQ4_7HJAXaZccCOzHY2t9EC6AP1zclV24aerHSdwAE2KLqK9UdMzGLulhv07CMfgbdJod5RiS_hQXF6h.GtMux9CouCmOVs7YmZLiVK2u4IW44QoL2ydhi_WjRlxDsQNEs88Iwf6jrpwStNMgy6OMxt57m0ta9jw46IglgBM_xhsWdoCWFGXBvsc7WAAu5RqBf.qWxMXkS0CXYJC9bX3qVqNCCyIpI_6au169rdnYEikP7BRpHbQ7gQuTcvhQmcziffSWsDQ7_AVOzx_RKO3zHCgFTNnM3K1xxhx6wQTmJ7T8P4844asyyZgqOHgOTa4iyVrEiRPDKqVZI4fyu9n0PC8LjbUZPEtenwfWhEq658pLITVmGWNX0WM.u1fAsaSxg_Zo0FngSeVyZwPJYaTxK6e"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=913673a59b773fac';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, "\/10010676\/iso690?__cf_chl_rt_tk=UI5r8VcNl8_BxMIHLuWs_HEtQ4KiwTaai3Y1Zf5c9Nc-1739802379-1.0.1.1-fE1NWafn7KQXSuqfT4Nr_Eo9EKmrn3oCk8Tei4xME14" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>