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: '913514e05ca3a8fa',cH: '1nSjRleuXCvKvTwExqgSQKzLoYmbq9Ukl2hBaut1sjs-1739788011-1.2.1.1-0RM70pJoFQdfXhtHLmNa5rcY.9m55DeYc81WSmaboMadUZJ1Z0oMYNB2pMHt1T.Y',cUPMDTk: "\/13806\/apa?__cf_chl_tk=DCBYy7zFCixuFWmT1tXRMdT49vsUIRdY1zQzZ4TQJzk-1739788011-1.0.1.1-DlX2DNWl6IsKkohTMPrj1JSRGnV_40AxyIqLdXB12OI",cFPWv: 'b',cITimeS: '1739788011',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/13806\/apa?__cf_chl_f_tk=DCBYy7zFCixuFWmT1tXRMdT49vsUIRdY1zQzZ4TQJzk-1739788011-1.0.1.1-DlX2DNWl6IsKkohTMPrj1JSRGnV_40AxyIqLdXB12OI",md: "8y6IWZ_g.4_w9gQWNETok_jk.DB226eqNhDpXJ5paik-1739788011-1.2.1.1-mGBq9BfFrlsugu3vmvu5_vzIfFolANNgct9uo277eyL8EAJ2UQNYJybh81cvTxriFWq4xrDTxdsiWvlK_oiq91rCkmineFYPjTCwRDLzPxZbZE6OXTAkBJkEsBuGD5gmJ7Eo3tfETIyTg22l0SvcfifX_b0U5ctQPkPUBJMpEbTgf0rfygSswxZXYUhtpYiD6kL.G0kX7ooOQC7feKJgP0aeMGOE_nooHl7XN3wjFhTsHT9bmkN8VXAWdcOYE7UZO1CWYpvd2PDW86WJQ1TIGoamS1nOw_iFNBpNPD5_x5DUC73897jpbzHfbM0VoaB.UQhvEX.dmmjaSH.hBzVO0zrbBmbFWzmK5oqriU34anLsL0w.pMi6RQPFb_C5l4nN.MsuyLbWKooCwhtQcaE.foS6xQI_6j15LcLwpVGxiNv3w_8RuobA9aeL9Vs5FQqVdaMUZ9zOFbMLxI380jgqTyqBVDIzL.lTgaUaUfFfSmyncHZNBYR6vSHu.EqlnnacDfsAPf.mzKI2shLTFALba_5la88W8bIUQnvN0rH_A9g00CmWK2KIJmT0Crn7O4SuLOhujlAzch9_q5vcwamr0UKiWMB_Dl_oLfcOG33epQFgBsVrSmo_c1jphawsIqn1p2tfqbhSWahXRbn9C1ZzokqNnY.IOh8ABvnmsMlS7144R7uOYCYu4y8oGUjr0pE3ePNE40RurI.n9KzIKaYzpQaIJJZvaekVdUg2XqYu3jedeeXFavHkMwfqcdAIq1jq8AfWrvDqaewfjaVIzsdG8fYmrDlZun9XpxIv1Kk3BGl6Snir1uFmdAsatEcqrn1mbj0IIVgb5R9A9SnCDKS5XvD0ClTVhCP0_Kju0SxEBesCAE2fxE3VkTqzOOurRdhLauxXrKXrogOVsVxU5Y0Rwjl7VhpZCelAV68QZw7cxebp1oRLF1wCqcFLLE9urG0SRVD.13DOjL0thRZ5BKC.coWv47OGOT7gWKLFdcjYwyOMXnkPwHGupDzYYfQE3J8646mdOyi99pdHF6nGcx8Z2gCzIj7m8YsjzZQ7p.IL2ERpfr7c9484DkqpNbmpA3YiHN_gr4sOWCdr29OnKqXm3izddqEo.op3IyHXTjkPMo3aCFavpcrtC65du6GaUqHKyiWFRHS486Hq_eqzOBSN0vGwW26nOr4TJpnS7DslMJA6wQbESUbb4Btm65pVdbCrbnKopL7tiUoec8XPDJVPRrjDfT6ZIJfiTGHWjHBHDP.WHzXhlvIv0yeBGf5U4YML77VlyBxMKCLS1hm7rSluZMYnEF_MhdapOWz35IRK3E_FeBo.snk8Xu5gK38qHBjMrUIcRj0.7LWPbG2u6EqLdRHtOtCMrwJGhwa.dWe84vb4NKOr3l380Q_Tysi7_529sK8WVo5zIG5cGRKoImixcyLuyKBhd1UARFwesm7uPCWuNuKzlvLdu.30TzOqL96LdPa9Tl6zaEjk9aEAHG8eqzvlji_wtMYMWQRj6wTKyBxdi6zaqeyzXBsYwndRyb3lp.GPsgZfe2nzfCyzOsjSGmuOuCv_y0hiac0fOuZElNyGJlBNotQMbSlX5ju0gshtvG8TSh1179LJPDiAgyvMu1B4UEf5b2wCSVn61jgqtAMOqgUXj6A_Mkdcw7NMRNej0gnRYgSQ6hKSWOz0zdF3Fi5qahVtLuV9.obLQZzQEuV2AoMa4pFrHQrvSQ8tYNIHQVdX0lwXghX6WXubiZqeynX_4BcLrkI_E2zxBtc5_S_0RIXvqpD9Zy7BoKsIoX1DfIu0ojZ3FHr5Ny4YJqk4Rkf9pWjk.rC_ksDslyZIT3h42NelZ5133OwsVxeQrmyZGO0dto_NxVMilGXDXrf_urTGlw9fBaTAbmFyimyObXM",mdrd: "NchypHhblCO5NQ83tcIMwcneGCkqix.lSknf6HANwKU-1739788011-1.2.1.1-vfTCBACqwuzUNC4d_JASLUE7pYEhLxaD2ZLVQH17ltjcrfT3z7DoFq.8QD.QPkFWDFWREAwI5vk8kxKoclOclE8BFUbrmr3sbEPQ1.0e4KMoViE11R1o.AayzimUkk7kYHkuV1uO7WjkTqUaiwEkLlxSCoS3Onc3Bj7ABYHusBayU2151zoThq3ex2ssCCjir8NSrgFjZkCGG16zMZlDN6qrpBKiipF2Kv_QMP5D.SwB1Z2NMAhlUqHVqA8ChbLnJJy8QPWrEd3UYDZKRPvVKqZdV0NLcNZH8x.dJH2NTL8yh_Ijjs8J1MVqBRqwdVSaKyiORfXhcrQxq3U6pIWeyk8MblaokAl114WO8jbZYURH0N_bklbjIhF9vv1x4OoWCBSDNOIsbBrSeRlvNiZxsWIjOaf590fev1_wj0gbDyC0jYjLkDEVLISlA7fE7Z5rhsWVigmH5hFSa4vOYRuMsQozIRAyzdQvRxkU1kEWRd_6iDIVYpMkkAWKTd6VgnUIYQyLLSfnhDjXckDfFdKIoWRwV8tx4fjoFzE4MHngZtlDpN_9vmqfhe69ZToVsLzddno0pFhEmEqMgk64ErQcwziSf.z.tNl5_fWFUr.w4AnLFrWWejA2x8Y9dlDOCIg_DULFMb3x.3HWBX5PvFHAe6_fOJRn2FutxpfYHq9PWBbh7d37MJqNe2wnMvA1lyHfZGEvsx2wlezoIi4ZxxdJKqOSx3OXlFWSav0TM1WRVwUcWoCO2YcMoU4VAHxKBQueqrlAM1PA_8g6B5GcKQ7JAw_CX7Lqimr7_VnEXOgJWyg3Uj31gPBaqbPSVF82bxp8k.kfniU5zqqzFKZys3YODXCs1StLz6H0n9b2lgb1XYFnI3finwHw9Z5H6hoSHHp1uq6XT1NnmttaHvTIbMO7kFUaBdOUvgZ9rlGWrAN6QDx6EnPg_RxBpLd_gE6u.PKGLfeHi6fXKTDnJHkq7y9RmCa1uRVEPQeQBEL2qAm85PAMhzVun1VyQ4otCqYuaGXyQ.ENj1kCRdJVg87Ed0YYc.AAXwOFG6JhnGod5zR7M3sca0si24nt35hRy.OY_euLc5VLHq1W4KUbPn9P7IYb78jgT47OZnWdV00OqzBXGCtHh4305hK3bZjVjJ_WZVIDdrcBQvpYrJSLsE81jPnkBAceJHsnwoVjCFQLDabmwwI2LVe4oOepsZ7ierXofHPMHQXM8zHPf7U9EIMfAs8DDNqvV8hxKpFxQYmWw1h6IJ3DR.wnlLfPifH1aO3YRtv50R1NSvmrWCIXHcPArFjjcFH059hrO0PfuUvYZ5zV_gIPskQy6xRg4wqh98QxMjV8UzcVGkdbSgvCA6Wb6EZEb7RGiKXQC_x3EHf56PE4F_gfUXwc5GxPpQD_GvAMLyD6SMZRaC.Yvt9.jynOj09WGVnXCRV_R6Bo_o5gSycou4JqfCA9cgT9h24.Ntng5BJU27l_9yPl1sHXAAMqb3_fmm_QUO9PI2GTdW.M1hp4SQoT5ai43zi1olcmmMaacefPTLZ7h5L8tk6i8wTy4iKvNfH42ZMy6kaxOzn3hviZt6J.iSLjlIlNE0DOE5VPeZDy1htTXXKgW.aGFZNbvpaleKfmR7kxqN_EPVHanJueEMBa5QvaeGLBvOz4goK5hRtnu_jI.gc0GydCah0YbPlZVDntmeZDiFRKJJL6jP.qzWTyVc8TkS3yJXWwrXaO6otd0unqqDqx5vMId7Z7kw8F7ropN3oZecPuqJK79mKDnb8mGwMgFqGGFi80dnS6ocYKwEj2cbc0qZHmUda7h_QPwBIbuUxMl1K8bvualALQ50azwEBw_Avp0YTuYk_It5f8bZSX75dzr2YZauEb6a.nkiz4fLq4uKc2U7OUN.eUReXrSAVRKARWWi2JZXT0AIImovHk7ag88UYlbTZ_Y.GiaxIq4YxgVxFMYwxegLmS7WB_yc3Vqiyuh1gFdBUGbjgF"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=913514e05ca3a8fa';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, "\/13806\/apa?__cf_chl_rt_tk=DCBYy7zFCixuFWmT1tXRMdT49vsUIRdY1zQzZ4TQJzk-1739788011-1.0.1.1-DlX2DNWl6IsKkohTMPrj1JSRGnV_40AxyIqLdXB12OI" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>