CINXE.COM

Just a moment...

<!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: '914a5c61adcb9c3f',cH: 'nYtvv_CtEZGzfZZcRrTXY8cQePBIkd.9zAwHAiZnvJI-1740011141-1.2.1.1-e6HRfrnfYFX35ttHRASwL6dVhPkRQ8snSoz3ZAeqjLFCKIxCI35OhmAAY.5gFSwr',cUPMDTk: "\/1398\/apa?__cf_chl_tk=EJSmNxljrwTwpRr7osCvoHxEfMmPZRjhx1x2QD.jOwE-1740011141-1.0.1.1-bvIgTfiomCDRzRy5JT1KBomf5bg0CwymrSQAH3m7Nbw",cFPWv: 'g',cITimeS: '1740011141',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported-browser",fa: "\/1398\/apa?__cf_chl_f_tk=EJSmNxljrwTwpRr7osCvoHxEfMmPZRjhx1x2QD.jOwE-1740011141-1.0.1.1-bvIgTfiomCDRzRy5JT1KBomf5bg0CwymrSQAH3m7Nbw",md: "Mc3iHKdv5.jVYs5L0xVKWNkRHbkyuoapN21B3JETLz0-1740011141-1.2.1.1-6W.c7oMxJcXWWDCC96JtWByB5mfK2E3Swb7xVK3RRxUirsNdDnvhYFw8Ms_pOI3UrXda5kj6R1oQEvHxILs3mmKh2frSyi3oMy8zgWYblSNW.2a6S1c8Yi9iZaHwt.5bsY.kaIoYiO9DzpNE5bUt79M36MfNZkd76tIUYNXwzb2cbehobxtXM8mZumJ9BUXf1pNVTKa6R4OpQikb1prk5sAFkBVDK33KLWVF0nv82PJrYI66a6oTauZzIOaL0OsCao93UOvjyxDptzYyptqXiS9z5DrFaZlaX.VFjF0nXm3PSfokU5F8RVeol7ikk4JaxxFDxSR7sojd_10WwRdkLNUHs8r6tlsS6hyAF80kIqVQqe5BgTcWqdPRBozD1fwrEQbUpXVgmZCuxakvb0azsicZr3EEtaKJejgFED.Eluszv4cv1c4MpGoS4Bk_Xa8NnMuGKKlRX1qgMIvK5U2ffg4NgYbaeHlcELsVHvBD00GXfI3KvbtshOIOdj7xPJxKTJYFUZ_Zjj8XgoI2816Loj3wlt3jEN0y5DZ3Z0IOjBcOk0Uta1DfyG4U0GuG0X9KrwXnvfdnZ7iMgLW9_xm.ovKzNKkCDNPRDqdqB3RfQPGTBBgMdTEVMTcEho4dLNuVlp.hUKV2ANLSM9rdOgxTJdGK8A0.yqwnhxkHo1uFbxKlCnSZ0CO6BELDbUYskyvk3DLr3jtgrR49iXqLd_zbp0.xaU1o17sPPQxi1Y7UDE.eOJkoccuwK9gBLwj82QYGZju4LEPY0PgI4y5.bcZeEloUShdr4YG.4TWDZ369JT.tHApPBTyTv5TGf3GiRbTIHJvn9deFNSbanqNQSzMVoSfDdQ0jlSAPDVQAkIV6ZQuhjl.cAnePgn9fiZBMVgl6qQFYhd6ps0lbrdrnhFoavFz3FK71L7SydLF6wuz7PuTlyy.Nxu5Bumn8omP8.JLyfClxTnydkt.zUVSgLb2tNWyd9zYUx_nZZSr.5SThZeGoTeshPD2jGWlp5guAbPQlBNqhaODME06GIaw5JiLJ3uCHWW2vBLKnXmTD2HAVm7ysQ.hRvqTkCGnzNpeynKjdi.eQSuc84rzFpZLCiqkb2BfziVZhbbBoVvqhFyKBm7mLno9kw2EOv6qm2phcLPA98CPPE8J.a8zCRzDaS.Ls_Drz7_MdWiMN_vfNcAIYwW3Z9xnDHL.._yQ5qJtK3dA7W8CaT0YI7aGk7Hh6jpVgT_gbcJdIZ9A13HSchCoWGN8z38OVBhHxqyvBR5VrvpBCc37PRLle2HyvTEKffiukYXA2H6lfjDkevEX97v65ZAIfUez9ejQYFdVmNmzSx_8GvikE.B5B0JIvHyqNQDOBJE9VzDIG86yB4hFqetp8uWw0vY5MBMcpj.03YTmIj.r.g7C2fwo6uVmIgshnPkdpX6Gu_1GgVAQmyL2A.QM6qm_8joq6qW9YUR.5XtivBrBKhjr84JVMMpkpnO7zBEpURFfdZLMfykg.52GD9mDwQDUlTzOwGHJ0l8xQifU6EmZE0b7gdwOG3GKcyHjl3w2sumxy8pc1mfp.DWZL4H34Xo_.f.GW25CG9vx4XuGhE7lK9s9dq.EEgt18RkjN6RkyhP8PsyIhfIYWF8CtT6U0mSafOIsScIpE1lD9hJlTYlXTTn_WFBK3eMQlF.8gK1zdnqdVy1VeLIBe327qom4.5XOVyTboHFYw7Uqwj0Z_PWLsd4H6Ar13.Fu1_RhTQQiNp_c2eLb1M.oVR9uZbrjBlPEpXvVtUW5bM5uZp7lo018fPnGfK8JedQmZWHIJ.FqepFuIVGKYgvtHnClMUogMjnF6eLYcJH4VorKcFLUA6kJgSsA9GqIMZTCUGPk9H_m8RA",mdrd: "5wb5czhDLlDT0o6iQLazbaKcgkD5rve60n6e3xtD21A-1740011141-1.2.1.1-B4KBHoi27fyuQd7fRN8ojUbCyWBkgh.A9iQiIm6jLMT4DVyV4urZgXcvg7vjeqvrcSXaa0LhN15uoLG3oqiIhe2KzlhSLtlGO0PU2AzfH24tWJQlM6DlyhU2ELQBnpGQUu.iXPeC0.kHncmfsPIcH..FBVyFXZWt6eQwjvoL2wYm3lPP22IAlCGV0_BGnorTTXqQ5FLJy3N40DXErVB7PKdPR6uAOnminaLvS1_2kXucv3ZGtCz2at.P9JWtmipdKJHncpk5e058f1TDajRdMxOYYguRjt3e2XXn_RNoczUIoK1_XhmKajUl9TAXzHDLJoMCfeMIB.jFtnqvLQ6Q3eh1TFdpPBpUoKMI1TnwH3RbS._dl.nkDP25PcrosDAXvFFX2LbklQC7.UwrbikRCmuAj1c4bNnN0ebuNI5wwWfuU9FB18NdnhsAumlqx4V.cv2QAIrk5B3vc7C2UT57CmBCvRWY9NQUXSnBFMp.sQpv7lVpSBVobPIwSlUkQ5_BJ9OHzIL6_rSH5cM6feJ_GMzMDUSd.nP7yHSwmFLyIxYgEoDxzt0ih_QRkx2HXfNpZ64PwaPgotb68aBv5544xvfYEIZvVk3wFd8dzrkP0GSv99QcKGl96hM23bAYkcFsUOS75r94AFC4jdNY_OXcEIlipy_2dH7Ui2HR7vkhTEZtRO.HoZjRE.A2pnEFfrb80Vh8cbH7ri8qsiqCyh7JFolcbyp7Apdnf6tkNUH3yIbEnKy2y49WZIVErCnK4wVV0CBn35GfpWot4HztsmFV7HyRNo.S78Le7yiCejhRpf6_aYpg3REyhLqcXQF0waf6DgU1lpYLgyENmL1y1i6KwMhkdtYxaSE6FBvdwkQWFv9vYeFfr_7BJq1MAZM7iB3EwaRbPcrMcP.Gr_1ZiJZuQnxYD7.1XiF.RlZenM975JvZS6_ClfPZ0mvwds9kb8Q4ugREv.0HG40mbN5t3K8BZt69VJ.zteHSNLqfvILK5oaCyXGzNPh823bu_XOjtPmt5Wvzsohjbh.TaA.hGEJrlpt0bD67GeMc4LvJEnjay38Kp6gAd3VUNo7nje8GCTA2t5GBNg5Cd1xVvJA8pjikUsXYjnpfYmM7mzWi4RF8UmFpkpNscTsl9eNjMc001q2BHGQwh3kUj6B4m2DiBwwZltZam4_HZCtKYbba4vVU3feCuFODk0l8CCTpFR9CuzkLJYAi9nTEo8vPsYb0EU2ZYlSSlW6a2XfMXs8JEBsdZpH2bGmpVT2tbRQusyD2fZNzGqgDSJjdqHXMAp09MLuYeewPiqgWeBfEpGrwICtsr8G3fEdEvV603rYcjSN27tRP5dPbiHJCbU4o2YCbVhP2.QyIfmxRvzPmtlUWZZFWA_iiZ3cCropr_taPZMtilAQgr.V0sZisIoKaw9fFXbmZr2J1rv92pJTsh1VQmLeMJHwJPVJalx5._zP92hgmXmlIKDgDcmETL.moa1Tx.VwLQe2Ri27cwdF9mdKou1rqiGqKs1Wy_5OrtZT6UuCyM.GKAWamhxsScM80otDkWpOzLVXjRW_q8dJRJcWiqEqjxnafuDEAqAtp0cjVKqou_8Pk_nZM0YpEvFTdhiw_poeSdZh6N6RJMPEj86BYXVh7hWFp20VU8cdZIxTHu1kjJdXmnRkxS2KRW48lrpf86DF5L26PlmpPcyH1mQDyv8MX9hiUTSo2UUvz9knuzpb2Vw6SgtfGZWW0Te5fGAOfxLyHya_Tg6pFZ8EkUhelXZtPuPCF8IyiH_VUfgtHBQh281QkJiaQ_vT_3FJNVbXLPnH9Ix8nYENwa7QwtZP.nxp2.2gb3tMXBc5SNZ.aK0TjD5ddqdBGWVZOg51M6KWYsnOl2GOprI9hhG859xkWz.FigQdgLHF_3UhLkC6Ne4CPJvrZNYFqM0sHYROElXdmdEkh19KIe3uiBoVgoMFGwychYbo2sELGSmI3uCli5c85.DeCVUCBsXDGFkPWT8Ikgn9i8A"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=914a5c61adcb9c3f';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, "\/1398\/apa?__cf_chl_rt_tk=EJSmNxljrwTwpRr7osCvoHxEfMmPZRjhx1x2QD.jOwE-1740011141-1.0.1.1-bvIgTfiomCDRzRy5JT1KBomf5bg0CwymrSQAH3m7Nbw" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>