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: '9134c4bfce45fd94',cH: 'x.rn2yT8JgC6MKyTfjnneKIFkAZQ.keuHoHDjS329Ao-1739784729-1.2.1.1-x.EMFiy06nKGmjz3W6GDaZqX9c04ZfUSN5t2yeiuWBveoiDmxEiaBhKUfPFsJII9',cUPMDTk: "\/10012438\/iso690?__cf_chl_tk=QsZ9jBg_DpjMeoIH.orFK1qlhsLmKTW70jXn1sJB8VU-1739784729-1.0.1.1-ZHno4Lzqb1WV21J3aOXFY9Ve.f4B4L7tnXsOSduH1lY",cFPWv: 'b',cITimeS: '1739784729',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/10012438\/iso690?__cf_chl_f_tk=QsZ9jBg_DpjMeoIH.orFK1qlhsLmKTW70jXn1sJB8VU-1739784729-1.0.1.1-ZHno4Lzqb1WV21J3aOXFY9Ve.f4B4L7tnXsOSduH1lY",md: "b3mjdzj2n0DUjNI2gzyYfcmzRWY6lxslFEg748TpH20-1739784729-1.2.1.1-L1_gpcH4qb.gWOxFFcBs1zFhg_IoI3mtqVaTSPagLSMDUEgKY8Ap3D_gCGqkwsfNGz0vST1eytMPeG_XLIgptyELCXR3T_vJAVWqNDkm5cESPSovuZXHxnFeK4Bo6M5K6.CN0Zhu5bXzBORcj2NPgSYpTVg9Q8AxnqYoQel_uzz.t_zcVAV3Ajuz5OZa9YzlH2AV5NKPFWhnd2zP_JodDCCz2gBBh3j5t4sCt96pUuPfTKt__0Iy4Go2pWSf7z5V229Ex8sPFDOE5pkiAgABORiNYkc19hKkMmbkDCTPakTo0jhI0Zsm35oIkIw6wB4AxDAFuDpmgFbNpMtQybzr1cxnr.9lvXKpBRlDUMuElA4lI_yNbp32a0mDKM77_iJ8PKDoNOQ8VxnrCvL.adSX5Uz_lITxCZJb2UQx4SBg.sf9inB.tPIVkUVLMgG1EO9JY0_2wwGLIsZKp7Yfqn.24f0g_glhwqGRu5xbdyF2FNRm45KPvHlz7MeD8EoMTvbe8gu711ws4ctUBATXBR2c2qK1X9AvUEgXMyd1ccAqk1xocROB1CnJTjz5FtV2KoLc137koSnPeB0p9mWe4AwTubjUONcZOhdFya5FOHfdAGrGLr9hrxRnQJJrp8kG5GdiRPca0oSKBU_k92YOF8aPC37e.AUvkuTglumKnRyfA_RUtmxjHt4KCpfTWfI2zSRvpYtKMfAQR4Gb3RJxqiheqLvbgCjVvNM7YKMfwEI7hDH0rlpNz6QKyLt74DrfJ2hmEP7.8q73Y2C6r4oRSi6rGlr89HyG2g_9vgGTVFW0MSELGElBN3P.JTGTQCgtaUeDxXaieIE2qEC9bVyPC1blhJT2Tn3mmXQF.gi4j9TmqvGx4AWxm6XlPN3pOU1EI3aBSn1ZIO71BamiJaAdZdNZZoPkGZrqyjhrXZsMxN9x7pnAzcNZlw0wdQTWj4UPa9cWqFBlFJSEXORFze6fMDwxK7v0eF8O3iA34veKVTdvl8bjZ.UEOs92DgRFw5v6IMRMe61bS9oaU5ay1qEhdsZccrHT9VL4HdrK1_nCTPlTdGe9MCVa.ixHJMJ8rTf75VfTOReSiwKnEHW76jbcduqZbstat5q6Ao_8DgC44ZSMbYGl5kGUvrErFN_FPFk_t1BPNONu70HJjIlfJgoBYM0sPlLaF_PrYvu7gOYBS.b7JH93HJTLkYqctYfnD9GdzMTpc3B0RWWzo8gq.AYeqoNnnvm9K9CU7wvlwro4KsaH7gQgFWG.GWLFNc1K34N_1Di3D86w4d2R23rVXNqLXVU2uDNAVCZgLu3M9xozp8bv1wV51WAppp.35CbAKALcyDqzoxjZ6DqEkx.GXlEr8iVRq1knq0kJ2I0uL1jAvvjlq3979IRp5P5aHVyx3hTqMWNGIXTBB6deyr6b9sAMnASk2IvYYUHrkVelGLmprxs0fFWSAgX42e5_xV3PzQeTdhVnlG9yIB5HjV02EseA5UHOoL19LSrC4YY.3mFkQERSlIR2idDc10.Zb8.tkhz0FSnauxwsSaCZG6IIwGFJ9xp1il8PebqvtsvqGPv6_KVzE8ycDVHyajv6U0aSNis66lpSV7vKDHvwCOxq538FRV2jJhZ5g2d_NQhMTtK11Wb55F3pnUhvxlDEJeTsvwbqwA24LlZe8YSyRcMIlKoV1lX1xJdu0bjaHs1.EFXus.T4VtareVc1n_nrc1VbLOrx_RLRCEw4CNEHGbpNv371p7yVDajdE_ie70OkT5fcuu8wdEuMnHDNDhb4TuInCcEGDbPOOFQ8HeCHNGuwfeMOHEDHSnNQXZccBWsyt9MvPQKeQN7WM6HALAql5R1JA0moLixeNxc29oR9Umafr2UtdtIzR_kZcmJmTRB0GnQFy7HASWg",mdrd: "pzzZht1.3lqzS_Lpb4CwjBBK2leAHwDXJJWh69fRZ_Q-1739784729-1.2.1.1-AjeXoeP0_mLloADLVWlJlNxjIQ_bkqFfXpVmIDOn7hugmG5inv7c7BXUlly9saWYifQqt0z.uTLzytKFMQhzI3nX.qpXjB.OiEQIiUke5wt5ZLKAI0mrVvbx7cxMQxCPU4jujxBf1NXNXoyhu7vOl4beYeg8qqkOSxlCZXsu.yVCg0HigG189CBFz8Pfs4Yo6L4ZFkMYeegMQ29vp22NwImSxAJJiO5Oa2OG6XMSvVD.yb0JB5JfLpRps4kUVyJLPLwcQD29oZsHqrzBiF40ssiBf9LC.xdEAgV1OP_Ir5M3jSDK7wvnmAL.UK0WV5WqoNh534Lbvau_uHl.KMPoG08GKBFNgJp2dRVS9DtQbtDhmnM.1Yz0AV6p0Oxu9EGzmin5jkQbmw8lHgVRlpDA1uHc.FndHA4FNICsPty7bmzfR8TdTG8a0r55jZsnTE8F3YJ4RS7k2RvJ.wCJ.g4kcI22TBUFeEKxf9WyKCUNvcRe3NuTqJ.8c0RUQRI1mItqf29Cls5XQGFBBhIjWiTe_D5NWJ1z_npi1KpNVucvWxryB5Qv8SpINhzmI1D3WuirF38S.i4tgfwee16i3jgcLQqoU_9BBRt5TOyyQx9d8XjhZ1ndgK0BADIDLaqxHtQJ3l4uu_qQoZwCPi.Z9FHBXAoXz5VwkE6PIfcdNdZVbjL5slXvukGexSNB08RMZClLmfXrjOd4tulGUiEyon4ipnUgut7GB7pLgBofdrSS.kCERM2igIPPN3Odlcot0jqmydPoPWlJatAkj4bqlUmNyFWIIhiK1uHTSreOozhAw6V9_pcmVnBn3TH35VX9JXtFYyeRrrrswMy4RUjxdjTRCyzA85X9JYvgynis0.CHj0hBTHWun7hxGM5JZhlMxRSucMdLolYOPwIkEzJ85GDLjDIvqIDMyOppTjTx8GJZ.5zbYFzqF3VUqnZs30dYWgSyPc4PiZR4feAH1F7zPSRv58usHY1sF8xvL4byzzuldrnZtdxY0IBJw7jI6pXpgoHeNMnG.Ejsyc_ZODRkO6PLboOf_VuEegwfYrtr9maV6o4UQ41GA0IiVCUdB88L8nYfVfH7lATqxm.LaDwm1vdrbmX9zxWJVQuIOWiubz7jSPn2794xMbT_k8lJSmdf88U5yMsU6COHbGPAVVc3PtP2l6h.9G8T.z842WdRUcg_osnJWOE37Pxrh4bGMiB7uFYqeA1toeMK1IlCItiqgsHSBpAJx918UQhAvsrOQYeRPTL5dYS3vZUHxuoQ4SrZK7B4MDdP_O7B4v5OgTmqngGW758wnvESdYCHlhbkiTKa9ZVrJe.4SaQZ1pmqCwYq7LkKTzsons7CVDIjsKGYJISeZ2uRwZwmegYL5QadnQzHF.Zk0DaLNf4qS3WskLP_x_KtZDmES0y36.5khxX5pCBCZcg63OndyEg4pfZOes1W7KEzH.r62aXjSh2ttDABxRPHo0PpHvQgwDzIlUX3YmfGXmq13DJ3rA.RKLSYpAOOkXuRCfCbrieLDaXdWm5FcyiCCdnuXHCW2PjJs5seG2o3dDDqBZmm0JFwSrUclApLIwQeAoutk121oZAtQVkmxh17fhw_QEczaCKbMEiaPmNW6OLZdQt.jVzl06tH_J5yckxoFHwjbsijxG7QA.Mx2YgVEKKqFu7hP7oRiXBVMF.AKZdXanOkbZFoMic2fn5PtKP3Aw2GwlAfiwUxOZyJBDW26flqiIGaz.08WkIWfOh2N.gfUYbL6rr0PcjEX7_A6Xd4lkZ8YVzE7Rg6SCMPexpHuVmU4m0U17g2KH_Y19Ix.XECY1CCNZTs4urhLySfNCPcjvcnytbGCi8WoTko58Riivp52qDuI0aYFJJnTcjIvXBH7.yncjWK9CBmVZMdLjrMBWZviu9ZabsN9Mg_ulUgo9KqytTc.IekAMAiRtb3pJmQMtVOEkr810itcGLHHa.rzvCVKS_R2lD1Na9sk2jp.lI8Kq_I_P0DuuZNg1yHbg"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9134c4bfce45fd94';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, "\/10012438\/iso690?__cf_chl_rt_tk=QsZ9jBg_DpjMeoIH.orFK1qlhsLmKTW70jXn1sJB8VU-1739784729-1.0.1.1-ZHno4Lzqb1WV21J3aOXFY9Ve.f4B4L7tnXsOSduH1lY" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>