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: '9133a00cd84c9fd4',cH: 'AYJO1AB9wsSKymy.VD6CKwByLNGkoGajPelXVlcxyyE-1739772740-1.2.1.1-naHn1TM1QKc.0P0p4Wdn.tT_Ka1O6oqmU2AKR2A4pmc4NeJovieLJxNafafeknth',cUPMDTk: "\/10013719\/iso690?__cf_chl_tk=sQaFi0QPygG1Mq4qAYKtucMYnYWv5NDp45fmvBnCxKE-1739772740-1.0.1.1-PKK_UEsqymbtVydFF05uhshooRB.iI.XGpRhFfnFzSc",cFPWv: 'b',cITimeS: '1739772740',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/10013719\/iso690?__cf_chl_f_tk=sQaFi0QPygG1Mq4qAYKtucMYnYWv5NDp45fmvBnCxKE-1739772740-1.0.1.1-PKK_UEsqymbtVydFF05uhshooRB.iI.XGpRhFfnFzSc",md: "3HTJC4MVuYCyP1yXOedViMk7cYzDhhZ5GzE1wyrjOKg-1739772740-1.2.1.1-qOLtw.3eS9puaCLc00uEZBpyaZPCW6ZKHnz9bPkdbW64DHlpVVJJb_QP2x7CRBWK0h9SqX08H5E1fUJU3K390Gzy8qGGer20lRBB2pu5ihoj7OFm_OUg562wi5t9GntObqhKrfd35EB3LgrGoiF76oJId58mQH8vRcxiqAA3qYstmPhBd08m4PAzNG9Gbf3BvzDPfZPDXa5Z28JFcEQlScP.lGYQxFBi_q2lK5Wo.sCHHxsCCODownu3KDIBhSXkdvmvIePUKWPBHxAbTt4vbzhtZEGfe7QzTFJzBBP5YlK4ZYLyloyiV_YEHOvLWSiSQx508RloZTnWhFpkOBuuxuV24d94uZ4AVy.MzcsWG9ru4.ymTVSVSw_lvn1mcREg9ZZhtx0DyClN8K9b3NpUJCTKSMV0VohoroIFkGbJjMGozTNnpN3Dm29lkdbs96JDY_pLLv6lmYchsA9_gY1lac.FHC_ruMtx1ncS95eQdURbH7El1t_vwxJD5xJerXh_DXwIMDYp.6lej1jsYsd5.NhTnKqURbYSZ7drCq5fDLQrtoNxAM3mJ9T0D1HXyu32t3hgYEzTfQwqSFVaLK4Vi6f6g0YwknAIXJ1p9Px1ZzR0mBU.8xxx7tF.WX1wpPg5qUSmctprHBrOpd0_Xv4ju3_CQgT.pHprBpQ.xpd41lbAKG5BJ5FCSGhPHzEoZndlkREseETWO1_WSFo3NrmICTKvlbnKv5i5qod5IcnRGgrEXH9iULTwHI6S9IpS8lEc00epDwy0mKS8nE0rq9XUIHdIHH7mrOpKmGfmQHGwGri4zmq.BJfZab5lnx7IA34e0ymQnJJhOgfY4lRu2iAP1lZZDqbP2wgbI33SIWLaKv1xDdtsZAjSwep19Y4wk9S3Zl.VjhusChmnXCaK0i5Q9w59XYFWOX8rGAz.2LAh6WQqX.xiWV9NWwaN.eg1.alKvOwnuRCJiClKIg5MLV8ZB2y0G1I1kAUTQHi4KrZzdG4rHzbhvNeeA1UWvwoay6R8S5XURPuFAo.8jUmr9zb8Ibzmd7GdhbFjhdWlm5yF13.vYrTkcS6XQ.eXM.RwNgVb0Tzn7R7jzu.SbEAO5CF4kxva.Mg1O_Cmq6RBVmfTpezjPlj5xqKpkNAiCiIzLKDK0eh2_LXAzLblLKwPHWhw0RCZf_4AhRZmtTE3IKpLF8ABm2WlzXkYkaPc7cJ8Gu3OZp.91hCTryyhYNlwIyvIKcVYsTZZBu8p0CglwAkm6V0xkqCocJANKasjVuZiWF2wRlWlo_909VssMvkaw.p1HAl2jDNNGSAnmrWQ5Juu9PHXQ7mjdK8PtJ1LXsW9cq4qzCCUqMnKKaseeDQKM5k93bKpUrqd2VQVtZ2XKOW31ccPbB_VDryheAr3.fFKtqvNgv1GHmKsDxb.m4c450US4QUrpdas2HSArBgbAgGMH7LIdSijkBIxBtUBni1MidPrUGZG8JtkyZTPWqJM8M8p.1AhBsgEiN6nwy518_3_DuVQAdsaF6y09YP0pmyXKeBYxZBdBPlt3lZQ60LFPKbOkWGOW3FXpfQDxhTDpHOGmvbYw7jAURd.PzjMp.8tJW2iiM3veyd21DW3aARlsBK7bzgpQ1ijMSYaBVJHKJsECan0OhDTrJuJLCmQSIQYqR7r.dMAvMaogbE20JF9DZQw0dGeniGfyTxQXtJRqdU3NPP9uRBU3_kLWD1V22RETHj_53lS0r.F5DyEmCQsYijGrlvxr2X_XPYHKsdHt1W3OeJUDSMh89.Zbk9x17XwS8_PSU6d9uYFvRkivWRJ8WQK0btqtYOCJK4Q3dMRj0fJN1Q0kSk8SjZ5sGvXhCLkm3rAh1sIKsiZmzpKwZgwycaNCnLE2.XSgYqp9UmBnu1ugZM",mdrd: "0NIXRNaDyyDRmB0.CBsAN6YlI5K3gDfSoutXNQiloic-1739772740-1.2.1.1-2NK.bTdsX34gcle.o55joTTXAEDEVMJ8DREzuKROCyDkexY.GTuPK0AeJos_vlVutktS2.FQ2OXW2MPouwp1CaxACOYzaotnzWlDVrgtv7sH695Qb_0gMasFoMTJQvQLmNGR0y8DNcC2q59V3tZfrZv4BtqzcyFn6oTuEozsSF.gc457IK1h7_s5Ph1WpX3wxqWlX9yAVklgtHT2SYE5NvDjmTY7K5_wKtWMQ3EfhC1bOgf30vp1uBTYyeD6p.7cvYIwx3A3weL.FNji.9ARyZihQa5siKM76XKEX49BIijGIE9Tg1rnvwyqZ8dszufi13KBPQW2w6SWyQB0BeUV0ZXGp5ZQoJHHUTKdL2S0Iu9NF15wazYNpYuuk9BdPi9V_fzKWjK7ToGF_drTmbQdC_C7MQxBCnUFVfk1krFTs3sqKAII.xDbMYWpfdMCIAMzW84p.PhUTdelh3d7MMisMDxKqS6eal1UMwkqyZ01g68EpPCv578E.VVanPAiqfSLjJhsAtUSJdgb.np5YFofRFgXDwHbKOYRVsR7lq23A7DVL.M6VzOZUvfVBG6OUuR_HERbAQmb9Z6HEZ87Fstfp4EFeZG95T3XGrJMkmSFLLGjryGiBDfaLSgCYvFNvTMObRDOp5BtV5f8pEXNmUhJeDTDbHp82jb5T8EDLosZ4Rf_I4A2bwT2WUFT_bHtkia38x8eKc0cipfUSRmbb.hvhN0aaw7.FkyLqFONaDQU6dWPNYt7K4MV2AHN9Se564MADI2QieebjlQc7HFn6IrWq6x4irPHVzdP9iFpuARsm.ZcgnxLf4s_fNAxE2ttscpicflhizndWWW7D9Vsefk9gxUhZGmzA5NEipONW3EPD4lH8ufq3Qn1NK2O6ro2AsArLfW71ExkllYopekOFnhCs4dkZK9DtyMugz67D.wzLfd9HuXq6kzQJMIgLjlmmfWieE6LMlWzHetZXnsvo9jtoHwi9CkqzHQxC33kjrTkQdIfqOo80r0BpOo79rQenVSM8JUlOq8FeKLqLonc6Xh8PN8fvgCLtSp.q5TexCGRbD9Y4EVIXH_uT.h9P.rsKGOBLyBKSxObvSo1zRZy83MRCY7TAVWm7.q7SHwx0ruwkuaOnp6mObOwottkdAqmy_cHM9fuRQf39v74jInmd3Kw.y3B9wrxT5EZiyof2XgcWfSlmsyqK8JbJ.6xBntX7bc1ppByEd3BJZXA7Y7ZL8gKSEEXuPDUt61iafp9.QNr3BcXWTN0IlZ2rsr5yygxrn5VtX3gf1vbWl0S0TF_g.ro2Sn2TCeb.ncZVGlMAiIn.UHqUYfKs3qhOgkCCSSl3j04CV_b2cZAQ0WkOX_Luf5vM0_J80LNHjz5erZ3wuSepGPkNs5q6gJsD8SjvORAINeaMOI3HpMfUHQdVrRSp5KQJ1TekCWRBD0yfz17BLYibVzBGjwJQIsxtHnbLv_k6sPlH3MBH0qXgmjVmXODdRj0YvqPQpN5jhiIpWLKlVf4roCTneq6tmzhk6lmHJCT4LFVgtZD54e60sEZdrI3NYBrJvhmsXZKJ.RA_mTE.XeeoyCfTBIbQyyjvKnTPCMdpRRnNJHmGQw0uKNfZCx4jZWpFliaX6hq9e1Xbij34cpEAZuh__y_QOV31ovkr8TVcoSbU57EHqWWe3GQwtBIPTw8QsWXIzuVxUQKViZXph7tyvWL.qhlaRFPcfHNxkH8rp272aygydddVcE.nZdxqA6917Wpb7_lBQ0M3uHnywvmoh_YVNaLHo6yIbV3Vd5I_IE96qxWn1Pgz4TTvUKEfZyJq5lFKM3cUq5GsH7plEi8EQYYoZLfVVRDJo.vOCB08_sFw51y0VS17taU_B3vmXIYINwHNVdY.5ye7pjXpb3E6VpUp8_A9aI0Mmn6IA1tgUb7ZHMMFHmHZ_k4OUo.xaJWVrla_vwTjDYA8X5bvatsldF3_vInFpRhtYeaupj29NLgda7XOpo.xLmj1ALVwnPUNA"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9133a00cd84c9fd4';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, "\/10013719\/iso690?__cf_chl_rt_tk=sQaFi0QPygG1Mq4qAYKtucMYnYWv5NDp45fmvBnCxKE-1739772740-1.0.1.1-PKK_UEsqymbtVydFF05uhshooRB.iI.XGpRhFfnFzSc" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>