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: '913574bd689f9cc5',cH: '81px0cI034P2AFCHMaE3PP8PA2.zJTjBXX8OUIgqn1Q-1739791938-1.2.1.1-c0NM2uwm9Mk.trsi8.vp6kfBOZJLrBFTQq23jWUFQa99u37PGB1b8ReTNiA2QqtL',cUPMDTk: "\/15915\/iso690?__cf_chl_tk=d35fsvdirAINCcZqqFi_ryZI5qyVyq5_oGlceeWdIEk-1739791938-1.0.1.1-5BwL2fHgDdy28J6ZyGlM4hZTwdB...5ryn9jjRTolAo",cFPWv: 'b',cITimeS: '1739791938',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/15915\/iso690?__cf_chl_f_tk=d35fsvdirAINCcZqqFi_ryZI5qyVyq5_oGlceeWdIEk-1739791938-1.0.1.1-5BwL2fHgDdy28J6ZyGlM4hZTwdB...5ryn9jjRTolAo",md: "JC40W5zGNuGUP5qznMhL8gV_iq7lMgWwTAmGM7r.ZP4-1739791938-1.2.1.1-DcLfMb5axOq.X5FiPkmLT8y9FvCV_QtI9OCr_upqwK6FMT8Sx1CT.k3UJcuSej91nAsgZfjxUNuBHpXxYGBv1tcBLPqRFEcnnTNI62tr0ojDIBSZb2WcZEnQHvLNbsrphrzMpwWWzU7etOF6zZa.fU.bNADNSOfjQxObDecMq0oGV9INIf0tRgYdg2ThZ_reJBfPkVIYOojKZThrceh_.vKnlIsLgZNnC0mAuZ56ubtUef8tTX8_6gfJ0L8ZWZyLM3Sg5dF.6Wu6Bi.vleqlGsp.jPSGEWkrFQMY7UAT1QNOjGTyRYtLa2x_dR2u9kgxS2kdoiOs9TuLFXjDHtquKEdq.aI.ObwLJn6ywLreKnCC8bvYFYw7Hj_pUauIbw14tllLhvbO0mtlbdfCTg9uSTIiY7bRLrVSepdgaJthIfg9nZTSKflQKPdvv5sTz4LcQZv_8pxiyBljDA4yhSVl9JCYTH7gI2PU9LZAHWiENPfflXBX_V2sTONKflw.KCegINS5udKS7P1vGSCnn..98Z2cCyjzBuaGXphGEaQiVDQlwdrO17b1f7cy48gBm70h_APWietbAawwk4SlfefO6dlxYRmOkUIBSsU2S3jvSfnWjBQkBWMk9wTsQ5Im6LnHbQLeYTTZCppVGdqjGacMVnfKaREmlRoyO4ru_2tftXoFPfiN7giuIY2Qm9bgk9lH2TCDLCYeK6zi9Jb01syZAj3cSGcSvrsrVsNCK0HeRGH_8MfHIw6k56B88kQ0I_F5tQBsxO4q8OPGygwXrv3_f21e3VSVGQlTmAX07MTvMSoGfhbg.vk43_FEwK9J8_EQISiYEt2V2CehrFlP1yMbIKKjWjb7IQ0LCk__5myptP6KkeIwVtpCUGvNOxym1ownulLovmdwoFu79NBYG8gvNCjRh.gV7hv64cdxNZAhXs5jieB80DO_UuTS38H_ToqU_mRqA8eJhZXSqEwAPp5ae6xquXVPeE7B6qsJ4bLd5FBaVj7ckTXVd5_UVFZhiwYlBLQZF3gLik.9o56W_D.b079SeXng4SsDUfUelxMbr_IBEMR6SKVXiwpy.NlSxDPK9j2waJP4WBpy5haQVksj_2bVKsk8wmhpIMvftk4r7tO_tYE3EeyP6oNjg18oSPAul_.BxJ1PM4EHxc7Z7nTycCYqXXCP1oy8C5XiX4iXobQDlTjvqaMJwHImubtqkriCrHCwf56ihj1r4t3B2YuTamyVEI.edSa518tXMxac.pIONkFSeVxxtF5gnsCrkRheRc_8PdSglIuZfIvsIQ.Z6vangaJwJ0voy_MA8KOoxsJ0thFf7FF4ZdVu2VNjx9DKuJY3vBgUAsgBIAGgBC1EE28CUp0Px2tbuIEn0dNgUXhbhxpGg8X9_INEbfu89IBHHWmEQXhhNUT5xmwoARc5MsX._7WV9u9FYZIIB_gNyQitzYLZDlfcqntPSE8hXxgNMIHSya2JUbOov6htBMH.qRO1bcf5.4J38tQIgbozkM7a7uSfX0usdcMTnAHX7X4eTIUcEW9UGz84PGs5fIQQPb02zkCTSRyIDea0RJ5f_3.hR8Nhf_tWC8U_Vo.3FgPTEz8IN07R5c9PFQGxUMSsuOnvvHxnMErQGlqJy8B0g.XHTODQqnxADjCK7D4kcEn5s4Rqbk43q5JxxVKJtArpFFOjG4sVb2eGXSdT3CuwUVkXHYSPtAKjCr_HX5v_2wZGJEeNo8zNJX3rs4FWDx55ufjf4RzkLR92_Skj44mu7t3o2oQ2kSWUPM.Y1qwGbIDW4LkaRR9C3DFbtZybuS4litoXl9rbCe1x18SDVyO_.NWmRiIWCrTL1mT8MyBAEy8hrGakwauz69_7fstEr0cweUgjKffsQsiGXkleSdDffZo",mdrd: "Hk0w4m3GMVPdWvVyonfoz9YnCjOq3P6v.TKi5c83UI8-1739791938-1.2.1.1-SUWWtgCU..26b6e3N.nkd08jtdg4IeZkJCcCAJMurj3wypAFiL4twxQ62H.9ONVYMU7hpuSJZtAHT.W8nm0mWsJzta2Y38UoqPKg9E4MBbcd3vG3_IIb5y8WRfGljO5KjgzSxza3a3hIrArnu.g6chPBDUUlBQ8dgB5IW9wp3Of0r_Ox9rQJh7.33dMain7oP7.8TfZm59OfoYz6R1M2OJJuMy8K6_ssC_WZ_Vn4JxC_wnUwec5UnKfVwp5CQ70kf9ZjU1FWoDExB3017NWoDbQvak.WZmmsH_0KWSW3.l7_w9EwVD6h46Qep4NaaHu31atOgwAeQlw9V0uJgblBpljpmyCWGNqtBr7ShwOGUOses7_JRh_yJFdUw1aHBAspHTik9S3ldYnVFZUtjESNsoAA3IQ6X76YQrxkAlXZIt93Gt1yxa3pIZRD.HEqrSL1x3eRsho4BGOMB3i4rXpEzQQWaGWSJ.EP7u4JeuTOAj7KDgicRZ1mxBwOKCBMAz2eql9YTCy5jgM0xgvrUSf5zfs77vXa8CI5uMSw4zKjx7rYu94WIU.CnOHIHleenvLZUzfN8vG6ZtFKmqiHPOEunZucutF99mCGUmNFSqRXMM48WuOguYK9m2npB9HnOn_Fijlf1hORw1hhlylU3t5QjMjigOa0SGW5yTmGLAoVD2Rq2BV9Gj1sH.dKdaUTWtH4sbg32e6SsRHDGA8n.p6_bB46B.YYy0lpT5X2YfjaaHffCK.ni0_vwn4Dob2NOiX8aWanAvN4UE6aUOTLJ9wm1F17zyT.yE9JV2dcI21zz0XikXtJuxaIX9TQqot8ROm1wIl71ML43KAb2gjKCNUgbC6yhOcfpS.SQ3NtzXXCItosR_kYZW_Nnfw1lx515YPWnArcMXaF.0Yvjn_5V8fRQuHc2SwAzberN3ot3D14HYCMwvowG9p.Ei7Hk3DuVTXmSEanT9_1Rz7VL8bDSyfGhCf6B3IRPRv47E5GSwTkFFVsfIvR3BbSgSQy9x53CeYeD7FOcRp7v2z818InlMx_bZ2Rd8YNAetuN0mlmo2J8QwrNvNOonydxhe3EsQKpvuDVssUfFbHS9QUtRtf91kEDA9hMK46IJUAnkiX2fXjrJ6zUTj3mWu4jhK8uC2T8MQAIPLng5TWDGrsPHMIMIBI4Nnuzc_xfGKDCxCxQUcENrQb7UlmjOGq.eRq1kqaswSyxqGUCPOfytK.393ElZ7R_z1KT0y6JTfz9ApUQs5i.BcBzoGtSXamzv4_Fvo3jEhFZDSLFROoLEQtRiHFJiEwlox1OpBnkTH9AAJNMga2oAOHuU8fFpe0u_NhvChK4XVu4xMZRvJsV29P9bl1_XuIl22baxdqJ9wJ8vSaJc_oGkVRmr68pzbcEfsqBgcslUG6I_u4XIm4wD7Nk5VwDcXIi1ECE627tNmah4cqOdbJmzx0MkHbIuTey2HAxJplgb4ZnnG0OkU6RW8fLj7zb7qnlDDmoE7T94gxT7lpkDQ6tOuwNruNSr15HjsOpvY1cm7ZQsH9rI5GxZOAJ.koYDkoRZQpJv1PNrrW..CxRzlobtkJBeSkSyU4zSMXFrxUXOpu9vG8HVfcvHmmioKgFJCP9nZtDeW2hJ.g.GeciB.CosaplftIbu2tbfZ18kg5TKozhZcylWbELuTQ9cGxorYRneT6mvSVRD0lYdwMY1eZ5uztkGxosb2.Jt7xq0wvwIPa8FM6Jpgyor.guXN4SWS4KUrW9F3fM3YeAwgGzHJHzzIURchIAHtz2k8mXsEes65t7u2WwSx.dB6hcxibveL3.duSKrpltXFyO003tT01Ak.CuTNcCUjbDJ88UBXdICh3MhXVcgZWHikAg71060gcZmObONj04PCi1.dKNNkqPIt7vFEWiTQFBOhyICPatqFNYYz3Tq20UoHq7hc5gh_jk_yYYy4q8sCotSbJ.2DH3dNg4mcaXs9NOJUOnYq9b1AaHSr.sIrMBZMsQIyStTaIvg"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=913574bd689f9cc5';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, "\/15915\/iso690?__cf_chl_rt_tk=d35fsvdirAINCcZqqFi_ryZI5qyVyq5_oGlceeWdIEk-1739791938-1.0.1.1-5BwL2fHgDdy28J6ZyGlM4hZTwdB...5ryn9jjRTolAo" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>