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: '91341e619db7fd37',cH: '8Z7Rjs4z8tucim4lQeHZnTnJvWBGa3sXJ4Bior4HauI-1739777915-1.2.1.1-rUYzW0M_4icF68weJdhT2hRCccJso.tfW5WGNdoFGFv.LTQLD7FzXssII3Kdrtyu',cUPMDTk: "\/10867\/iso690?__cf_chl_tk=VTgSUrBPdaZ8l2cOzOZJ0u7T3KLKjBuX3Z_sz_55S0M-1739777915-1.0.1.1-ELItCOScneYbYK1bQn9yMNGKZUKDPOOzp1o3Z61mnHs",cFPWv: 'b',cITimeS: '1739777915',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/10867\/iso690?__cf_chl_f_tk=VTgSUrBPdaZ8l2cOzOZJ0u7T3KLKjBuX3Z_sz_55S0M-1739777915-1.0.1.1-ELItCOScneYbYK1bQn9yMNGKZUKDPOOzp1o3Z61mnHs",md: "_kWjIS2OvZbg.RgkHCNRKsU7FlrNUT7SzWi1pLbvzLw-1739777915-1.2.1.1-zDqoR8WI0P0wJFS6cS3bfI2d2oJ67XgR_oKi0OH5xT5Mg0CxIS4hrZibHtI.0vUPZlDxMzkop06bX23jXMqwSaaKvOmZ1WB7u2FKl195Qc38dutmj0mNptwWGrNxenhgMsEd0nss4vi4WiQjU0it5MYgp5MeZtWQHIcVINr2q2cklxyyzWCkLYc.tt8JJsWFQHgUGPADbaFq2jekSfvm1VCeLvp0B.igymqHGnyMUqJFjeodUmxJtDomKQSlaU.YIYtl31DNhbHoSyD5jhSwg2wJ75bUYHwYWoTqQlXUeWwTDROT4oiX7z8hNJNvLmJ90fTPaNC4l5N.dqzodBghwDnYSz3L_k.ebmEZcqpmYPEW0l9FuoRlsf7lXvkeUicG7hEd2Dykjib1KwwW6S7KRLD4qXBh3AraGJLNpmoymKPJN4Smk4RJgyWnhurWLZLa8OxIaVPCQ0G5Cv4W1afn4bFiBty8OKTpG4SfHeiJiC.Zij7zFdbRojrEWWpLieiqNo1sp1QRTIpkx5t0QPRRukJHbgQmUwxq8KJ5RwWB9Z57T4URRYmASA8Ked6wRYrQSN4u6BwmsxuJK90tMQqwflhYcCcrXYOtp_gM1349CFYPnWiCAMvcUs0w039FYCIUN7KLSJPSpM19.URrbFdV.CdzEcUuQLnYWfkdpk_212zIs9CNRok3_GTQgHdkz54.F1ZAhbI6zNiLHOw.188XwsOo.ZblXDBOmJdo.jPWLJPMg_TCDg8zJGrgLWvwgHsA.HtVszZRf0TVG7uWKGCKoTbqLJahFdLJAP9wLJFK6u0h3ruBC_Ya1AVo7DdAvok1FDYxwWKm.m_9OQcIt9nzbv3sd.8RUAGLQ_B6_WC6u4XSvS4q2MiquEiqw2a2oSlosfUndpAYsZu6GS9yQ1V1T_6E2OE1ZchddQVaIEPNYoGxsLKMbL50vNvE23BsgnufNmPoe.dZqmQ_7qefC20Oa6oHo3fLx9PjymbG7kqcnWlI6LpcEe.cp92rzgQXQicDf61RjILt6ZbzBuLQ7P6Mdmvc80qwYYt4_iIgn1QYfq6vzh_U_RwoYCJ_._1zXULD7.oL9k3OlTnSoARcu1pYGOoGq0xGj287YcQ0_ao6tblg2aeqLfeGwA6.ZpvitHm3JEcxEWllOPLshcX_eeerRpubyn7M1DmJpq9Cjccj9WQl9y6lcxmj61sMUnvDjIKqtBMQq7iNhDRgXnBM9dzdQSfUk.iyUxKoEGMx84JTHA4mjrQZbPNE1dgs2zjy1N7pJa1h45Qd21feGEAtI_pETbufPRd0kntsp7XbYhTQ.Gc_Oy7AH8GpnL6_bew7tqsO8uTyb7xp2aJtfp7ANfr9M5TWEGpZvtE.G7Dso0EfTE8fxpfZUrwfANUZDUV4P1AKMx0O69Tk5K6louj4xmGL2zp8.kXa8PCtulq2fh17LdTV3vlqDnwQo7RlTAfDozMWJO.7SZ1JQ4HiMdB64AwSZveZm1SOkGIaq9YawYoVpKQ5fhFazl1TQgWZ_KwA8Ks33DFSJbarlX04WzsXO5r7bw3V7.ywqIliqagVai_3DRuyIaGJUGVlUpC9qw37WCCOcC9kYci.Kd0VcGEhZQnJe74LGeNzvV0czsO3cIM3XqOAQTQNT_9S7s2YdIUD.RaXS4zJ7zWO.lJP5lQrSnyvyF9Qedzy61gIL7ibjlf4rPJx8tVDLNygX.nYq3vVMYT52RyrIINHxlyU30lB.UO2KpW7J4IaVe6EtRpp.xBqz._FHgn0kfmu1wUokgomx367XGBNXW6twI_cFkoHH3Oj008cKDOf9bIDF9xw1Ejpfy5Rn4yVl7KP6bIhvB1e85GzENDmz5g9roNd08990wSdbWL96jDc_AiQtes99DV0eY4",mdrd: "abQOFdBHCeaCKTGSWcHwmyeBJJLMSD9253eA3og1FQo-1739777915-1.2.1.1-a3fV0PrvT2u8Zzv18DK7fDRsWVqWj32MTTQMECuZUKvImHQq6XPI.wuL.mvpz7JxUlNnMOQP.wfGm7fzxvJgPpQ2bjUSFHgHr5AJ0yVyxRd5_QgGfmWOBiYK9TrkE5IRZM9xba.S787R5R.vAoKLjyQwANnRy5JvBbD3ni5KX2zC_mpkBfbzgCbfeHHbkA1PmTzgOXd.JPLQVZIkmw09Cp.CQcQcnneLPb0r9ODc3SbnF3t7RE3_S7je4jlZNbsiypZXbRv8BpWjcTQhX1IApPGvj76fL5HYbsHfbjVRU9MGUnpns2UXDiaq.agStNS8tGZTECDJTosvIVaXsPdA4d2GvzmIMY0rqf3We02QmY3wquiEe0bOAZ92_3upYFz2RTDuIafq9.AweAyhu_Ch_laYNVrpdjert57Ys1TbPgZiLv2B..U_3fKbKqEbVHsdj3BVZaOhB9m3zec6Q7QWduncnexpix9kiIkWNZbaELHGbedZteMebNwTJdemkHRj1sI.q6jzNavLBOTjyt011NIlQNGjkG.QBcPxNdTo_CXOMQS9eyhzKYUIs2VxGeOkSp_yrzmJa6ICOPSMT8ltS0jSlKRkXEM9GJ_2FV4vB9FR9nImum3IsXxxrnhiPYLkQW5c_7nd2ufZpq1NHMIpPSKdeIQO7K5HpVJlI8pud1FtnNQZ8yo8hHM8WSMyxMGVHQ3NF5_ZF.OCbIGunibazVQY4xaKbYOpkWtIYcPwi69xjnNE2We_vXNsd.iFS4T33UqcM6Uo876yjvlGEV87tHWc5t.gj.sL5ji4tV8c75WC9OHD7Cck1VODsfyDZ_WJAKWBYMGCJidpJGwyvbICI2EakCHnnp3Ry_JhpExecp8TvLgxJNnlGnvyMCJPdyJxV83g3Nd9eq.8mwxwmjzEpTYpj66UpEWprrNn4qeH7VnNV8D2UbzBrUpb9i9LzpQrCfVTzgJG_3n.V3PI7iM5V7ycz82Bysi_wnIPBr0.CEvor1hOTJR.fju2kI.h5f4Eja_VlHJ_0_Ll1LF5qbejXKaLO7WOhbvmozfsMwqoXDYWxoVzgxvvSa86JjZkyqXknt72uou47Kp26FmeIWBUqGOHkEEdj09wKO3Cx7.m_aChwdtmwUHkOFZz4qunikYNWT67rBw5n1GRtTFS_OhzLwMnQuLJcBCqO2pps6tWFTkJFpUhbHHs6Ba55WO6KY0FFKrX5OO.rY6fmwqx40JeienSYXZXnDk17sS0pg78fpDRTxTD4wG0jQ7SZxqK1lPTDwo2qxzQyQJqld6ENRh6fHxDHDEu_rLzSHJPFa60LVpr9eaFIQ5cICOCqJLRtoWFfEG8lWYbmxvim3qWLeGtibeWXJtgMqmQE3cSv2ijFEXrzhO9tp2r3pvcOpOyc9dLs1WB59iVApveJ8m4JSxH.EkSL1trLIYmQTs31J_eYbP_Q7rO.21A6mQeaJQRUuIpfK2PJzqgmNAjp3pfsb2pUdxp3D5COelwJ.vCqxcoU7ng2hIbuDTGx3BpZjlybEQAunXVAtjt5oRyA84sJcyQiyQKE7_kpGorB_VVyIRLdS9vO73XLPF6DLWpc1iu21OPb9kZML2mVYLqkv7qLylx9oltxS2WNPFwYn8GMJFgwHcttv9rM8gCIzM7vJoi2_Zk3PDtTwEXUhDndc7oZPVVLmG3HszMkTadhAnyqQYBdBZP5HDSa3GW3DJJNuYaGGRNqzXvV44LJvYZG9R7.lfYmwtm5OirhYkABQUj6r3dI_x19yBTI0EZnaVstD.lXbMEkxe13s8Ey5ayAaAvfRev4bncMdTu_u9bnR7rG1OYc1C6iTbbGIpOfoiYYlluMETRQ0.Q18e85ikpHA.eyeXZBh.LlYV78NJO5kvB4bSjJgu_BAY1h5G0LJUZEXHJJvWUCSXWAl1eWslcFAKZ1CARf2EEXJ6T6CUewOwaLj9tXNd5yGYCgv6f6vmQBvwDgyU5"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=91341e619db7fd37';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, "\/10867\/iso690?__cf_chl_rt_tk=VTgSUrBPdaZ8l2cOzOZJ0u7T3KLKjBuX3Z_sz_55S0M-1739777915-1.0.1.1-ELItCOScneYbYK1bQn9yMNGKZUKDPOOzp1o3Z61mnHs" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>