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: '913424dbbc939cb9',cH: 'STogbB8z7_cv3EsyRMdmR0L3ZYrXDUN91YSIsDJGBms-1739778180-1.2.1.1-fKmIODjspK52XtvchjapzkshW1XFiA90nxy9ZxNKTkDtEy5yPhDJ49uqNN3L8Apg',cUPMDTk: "\/10010011\/ris?__cf_chl_tk=Ba9Nn_HygjE8cNj17dno4eOBdBSikxv2PIZwVMbh9Ks-1739778180-1.0.1.1-VnU3UMqQhP4m7bjtEaVONq7EUD2Fs9bNqqiRP5Mm8QE",cFPWv: 'b',cITimeS: '1739778180',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/10010011\/ris?__cf_chl_f_tk=Ba9Nn_HygjE8cNj17dno4eOBdBSikxv2PIZwVMbh9Ks-1739778180-1.0.1.1-VnU3UMqQhP4m7bjtEaVONq7EUD2Fs9bNqqiRP5Mm8QE",md: "otsjtvl_8vm.dsvp9trR.dxCA4WB3vtGTW0VJwF5VVo-1739778180-1.2.1.1-6tdjJjU.Wx1l.Gq6YyKlMu9AZHcaHKscqXy6LMbOaDUTfw.sl1iv_RRW9DDKuT_MRCGxYjxw8pBQ8ztaqLjhKSMMwr2UdPtFAFQi_bTEXdqbeIy7PhWeXbmQuyLOxPPcvskUmn9UFV18B7xz_9ncqjg06oFNx_WC6BETlOswp0S2Q6xlll0FjBMtvx17ANFpenz2H0aiz7C0831UhCLdKRxB5c18wrbHhis3r4Ul4GxsmEBBPiKBOkOOVjKQalLJFSPLI98sVupcliu6tqeBIW1GxpjSZGr9uRTScfW_opHnimiBccY4vBI4vXfNNW6a_3A5KQSD4RyHbmprJ52CAS9BYldFUE4gBuE8xGEpZIvEW5H4xWiwWUJw3orCVzDIT7VIyTmDFuT6iE49GVwM3KLsSsXO2lyz2Gz9qTV2Sie6a7ZI4WOAWl6oazNaFxrRHFO2OxrlNuqZSxcG4yG.iE6PtxQoh8SxUc7661YFKbDqjMVAKzs4b6U9oiYMMVFEmYl20pUV27LXTdCdsesawQKt2erscDgW4KcdkGjKLKbe4NzjhvaGNzbB9gr2L6CtMoNZsWIf_0K3O3d1BVr303Mg1m8nENf0t66ivk0ZF6kG0gerULdO7__ju4eeRHPbeuIaTfjFnAJ8zy38spzIW8m9.nWV5XAu7Rl2sQ4Bxa7.ntrWc1MI9c56L1S9eCd.GVfNxeOD9XMzeu3WzUKxvqbz2xhdx_54l.pIL.w0.IkMWcZXF488Zs31wGs7yfG1cLgIOAqyx7xLqiUkvGIul87R06RSlx63E5tOZuLez.zw0gvVq0f.CzOBrvCbvqOzuEcK.XDUQDwVzafzcTMPShArYshm1HCmimMpLbGBISmXybaGwYK8jprz0LwMwjDUi1uRtfggzXA4u_WJ6W2MqVj3EEsJUT_SZGYJFxUswroeBfQp0GuCsvWc5kk8sAjJPwveRNo6RrNdaPpxDeR_B10EpsDWZ5WYPJS1iRyDz6VOVn4b4z.I.ejlIV9j9rqWyeYBFNRSrvLLbcQlwhn7gDtBCEsH8ePA5DNoGSKtddOHVspi54xuHY5ehQNgJToWYRbKSEbEHj8d.FQp7m.spsflBp.vxm1Sj591OgFllVSwVIBETibbJgLRt8W_6TcStmZ7sCvEXF0EC1sSaWxVevA0WjuFUP.tcLlSapwS7A_NQcjmO2AsgbK4PyV87hO_AXQ4jMBmC3E0uciWWwPaVQcNnfom4pMfBEk9Ac6eMvt5ptnw9x5b7GI7OT6JB8kL8nl7KMjgUv9Whj6muzes6ENcbTB6HiSe.imvsmh9r3P9S9aa48_J.pgYiNyfnVCa2iFM18_RnvvanLq1WRYn07UZLnaQ7ob6m_XfvUt4B2KUMB5sGM61rVNKt6juM2CqMZXD_yfHePwAW3qu3NhIrSlNNXl.o3et5TyYbs2odxlPcBy155oXBSGMv10sTTcDKedev9DRydPkZMQyG5nrnwJYzRqTG2CRCYLBwhOvT77E2TszwgRjx0RtZgNvkpTE4ONxDvM7vcL.ZqvfvrRU25OunoBX9tyqWfd8WV3fyMkkiBU_oEaILhJ858nel04pHvjMFf48k4E7KrnqX4_Ygt15Fa1FLRfIjaP2PV4Ra3eCGxeAlApbFMbhlY54gaADYjaKS5Q68XAINwXbRIGyNd8zY5Rsu6gxZWc0itKUaRUBXlK5T2qiZofvIZxw4ITdD_DxBMh1otTeZZrkOq40wgsOAXiIsnOr4jXuEM8Bb4mQYGlZkMu7m0U6Eb20sGyv5P_XxgUCWrVQBetzUATdMDtiLR44bmJT1oMDotJev8slU5b_H2pU5Eq4pPBUDzRz_xqJ.r4sR3I_eSWvQJoDxFnOX02Be2fQR7IxZ9D8v_Y",mdrd: "BlKZLAabGwnYQ6xAVlEC7dhnvdeWwuKtlHjuTiwOzW4-1739778180-1.2.1.1-Wer4CDK4f_vpDfxjV.gxggSnxK86S_GC0Gz_jYl8rv4.UUIik9XNJ89j_rs3aA5K0nQ471pZIHjdN.7qgasRWB1B0rsQOVAE4mG7lxgpoW1PWas5ub7hIQrR2_jphhnRi9a4DQiXAFx9_gXIS7KHcnQHCfQvrAlzBUtDcNVavftOesRpNDsgncGKqYlPkFQXN0Qq.0Zk7qA9ho2i1PgPFk.5SdrzMaQznXM_srrbYvcKivaZhwlh6VuISSxgATBwQn.Ejvc_YnCn9ZM0WEWH8PhgdGwsS9vuPkacbmY3wusy6bm7bA5vLjZu8qd8YqkXdEToe9PSahTtwOXw0H4vFkdEKaE5W6MCQ8YTVwFBkwVOhNbzSxOqIs0ZH5UsW8SdjdtPhkOkFa83CYyMtYcRrdciJ1T3lFCgHFcImZKH18nkkv6.D2v3FFBeVKsZjd4LwsbZpdrvfUjxbqwZq4Q5kQT5ezSAtMz44zmJy6RRNxJudoKQYZuafS46_vfG_Sc3C.Nq8ermgr_iU13D4AJbAyXTQwCe6H.VFoebB3wemVAxb4QtZ7Bxgbtbz8NbokZDwaSNdi1K_8gMD8HVP1z.qmlOOWPoUzMv6VAZfmFjXMaDnlnZ7LXdfTooeDOExdfUpYK2ZaGCaMVPjn7Hb0fhDQx6RfkhczbJso4eV.SPYiqcHi7gjsLJ3V9QhQmCMMVq01Bf.waNR95zJGR0OLP7rSpnTD6c1SJsasYti3r6OzYk3e4R7S2kJXm6eLVgCKSwYdWNWJe6k2E2W3Tcnzu2CN8j43NohlxA5HCXbVhrAfoZFFjZpJO0iRwVNM6epCDMqqugaHAzg79lSkkBOUN4Z5p_hf8TypVCUuEToBnPCltggJ6YTN8CZg6yw3uZ1HVN36tQQZ1uPDIm5QdbBz.dUukhQMxaCPVgTmy6o9pzzcG7kIwfNWF5CvOBiccRiOJZBNuA5ayOlrLH.jnNWEYhywBCz1.XQSZsJuSSeC4n_JM24hg12.3q6tVUg_jVcdGMcvARbbNVzVkqa1vWaZh.72iYZcnhBoeDTEcGpTsDN3MJHCzhrBxIOrSk6iWJ21vXgRg6c7bNYxYcmROSDdLnwB6r3VVftz5bBfq75rMaHqoH2oXcowhcXAd.Otossbhw8PZnP21aHV3zegW1mcDxYozx6tnci87veUNNb86xDOZqKjWyjdXMLF2u3ZVHJ3ISIpjT1wjvW6sCGYsg7NfeqVsy1LXOXNuPQoEEWILFe9l_SKWlvyGxMu1sXZ73qG4z7bA7n3LWNtmwNIN_pAtZ4BhCCw00Owhp_eIB7re3QVNWrXAO.zp6_ELVZNOsOi.m946F1bygb4kGFb7DdQ37xm0ooWFNpduJWS.ktn804nKW1y1rfRmTTS79Sk8VikOkI6JxFNOqCzVy32fRQ0RVMNujg0KvOUbwbOcgUDt9Ua0DB7hsRZCJqP85a8cAjLjC8m1esbgk8hs9gQBrgg6kwRUFJpvx5lNp5I__FIM3qnue0Sug1LTxp4n29yH1tOO7EJ4AO5ueRLhiiO43g5NOy5SAfm6QMjijP1Ajz2gJn.b8D8Jad35gKqSoMNw86zraYry_wMbEJ7hHG676JV2QkSZ3DlyfziP0R4VU5c7aj8aorUVakjG_aPar6mWtPfSt5r2XXRj946HEvBDXacAaUXgCMKqHs0pUnPpiXZ2G5JhYeKMFskkWh5AUF5823pSAFIUwOuuwykiU518X4kjM0L41GBwE1n9kxRA8arLpYCLWyod.lTmHvPhM6WuDIej6RK2V3iVkiSo12PSgIGguFGSEZnFFLl7Scz2gl7k1nLRCF4vZYj4_a2cZAW2GigMKT_QvH5gT_gZez1NUsrTIA5MOvTSXoYOl5hxQGUgkFSrvvy6dsM3B_QU6RISbm9z8iPKj.jmIZczv7hXRPkMxxGofWGddrcn_RK6VMYysG.Jrf_Z25h16yWKaQKjBl4I4"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=913424dbbc939cb9';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, "\/10010011\/ris?__cf_chl_rt_tk=Ba9Nn_HygjE8cNj17dno4eOBdBSikxv2PIZwVMbh9Ks-1739778180-1.0.1.1-VnU3UMqQhP4m7bjtEaVONq7EUD2Fs9bNqqiRP5Mm8QE" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>