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: '9135fe72fdaff88e',cH: '_uc5q1L098RbYkHPsY8mRMQ.kXLmhOJdKI9LMUKYnN4-1739797578-1.2.1.1-iKx0XbiBXJmaZLMaLceVjdTB1zj7wvmYpAKZjStPEu1WFRBqWI30O1wCe8dll4yv',cUPMDTk: "\/10000363\/xml?__cf_chl_tk=ljO_RtTNAlU3ns3fce3m6.g_ptvxuYY1rWUjfagHafw-1739797578-1.0.1.1-CfBJKh9shHYPaQ3tBWrH37DjewBCv9w5scqdJkV213w",cFPWv: 'b',cITimeS: '1739797578',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/10000363\/xml?__cf_chl_f_tk=ljO_RtTNAlU3ns3fce3m6.g_ptvxuYY1rWUjfagHafw-1739797578-1.0.1.1-CfBJKh9shHYPaQ3tBWrH37DjewBCv9w5scqdJkV213w",md: "bYMDxKFdTluTCT_ApH5LlTg09tXGGXobciomSNjbcWQ-1739797578-1.2.1.1-NFjrp1pcfpA2cohy5FBDeYR6fl_wT06R2izqjvkXvwVszWLTUV.rYst.ueLaOnVdg2LbeIGbMZiM0dvb.QicV6JHlbCBBA5wGUWdIOsxMM8hecLd5gvXPxfVwGRZYNLoLD8da4mJd6iBlI.Lpbl3gQ2CQ15o5x4Y7bywrKIDQ_UtuffzYY0IZBek3AP0ZaGI47r6XctNgFv5MHv2e_NbJOrOwgupSTCJQVeqYiE.OJjiTdxIpvrenKuhr7jn5KWZWUoqDDajra2EBcnexaZnnnt215cfRgzadfXVpyYKRPpUeHy3.5epcGCohvzyTmTm7DYjckVs_4ZCkL9Mxemz1Z8DQbXphuTyxbOZ2jtAgT5mzfVWRaZFlQY3ucmg7pMYs_gNLkRIBhusE4P9mcQM26TReO2tYq7ddhQloOSXsDQJQxd7O.CzWAmRG2TKB68jc1TxAV3X25cDRK4C4MvorvjiDFfONwSFc0_JZDbIRsSgkK7wZxktiBcXmcZq.s3ri7cLgcDPYmFsXFPYgjVyZzMjUOGAQAFU3yCJ6wgB0yw6AAnhC1lCTA7AOKfqJgtr_uOjU7Qv5wA9nGD3IjhFJkWzxOTnJoQqmnxRPfyvRJirMDzbKSUKuCieuhsw8zFg1ormmc_lPaJdVWzTzpLj_FYtdEvr0Oowvz95sXWo.llgf1DPq2hGNYlsDYrKVEHad2zWxlEz2R310DBigjnvPVbETUhJYmDeqJaB6LycDpTsoj8C1uEpIvQUbrw3LMb9ZGCaqK.T1f8Dzsa2sCY1UBXDJYUtzTWV9G59VKh6LvqcOUeNhidm4SpccfNU24pD0E6Y87ZKG4uzQHLn71J5lGtejeuS4JFnCo8tpD3Ba0TF06sjFp90nFNMhLMitfjULXvEXM274le_xWrjIoVzi.k2QWiVA7llbRghmoQvcaqFreHSU4fXYAZaAYICMY4cDKQ4mELA4EDRMeJJn11LIu8EqBYeqHeZQBY8R9jXBx3WZ5WjL2I0KbtZLrARhPIJv_QQYT_jPDe0fzmblMqsaaRCK3OzJ_ZzASaEhE25NBxvMY3D4LARTZPU4FV8qYU.LcgKnCbyep1.wyeFFCw1t1McUa0elIq4ezicrpJyZbskILkF7TwvcT_eCS6gofyjz1CFwbtZsjQDU7ZndfhgSBWoXuUwYnMwE1_wpT9F_BuCN6wOPhB.IqTaAp0.tQEiFmAojkkVAqVyWQ7Uhs_y3E7_Y34rMNCMuopAkyepP0W.N0Hqom_jiWe.ZspKluqQz6PklIAqWE6H0WSIDLoV0_ooNjAbTwdm43GaLp9EifFRtXqz7XjYH31e6Zan4z1mThFrguE9p5snQ4.x5b7nL2uC1xTUIFM9NQfFgECACQntc9ZUM_ggAZhkOYEl_zD4xMk_n8mXusJD.Qr3N1BbNvgFLooXb84cCKdGq42Jz5CTOLgsBSw7LfW59mqaE63Usf6teeMAINcBCFjonde2BPkt1Zl.1DDisf_OL3ppzc1rmJnFsOHFGxgdotIH1c8u24w26g.QvtXGqNUWWtFL6oXJ4QT3PzcQFfgc.9v2xY91voCOxS_l45MQ3xLaid2FL4pP_WSkTI7tj_12mbYV3srL5edtZtufv5SwwiFLoJGm0v9QSX7Qq0s5m51eaYqoXt0sS3fiyA_xnfEzUiDO5kvV2MsDhfw.nwgjxkL.Ok9TdphgD5DDXStpqRCqRW0FittNhaHJIKoEndvj..UZaUO47rY.jOCwmEBqt9gq6sP.FuuR89Ggw8TN8tXDFwJx16FjpGtFyyQC4xgutu.a0J.Gjrrpa6TPMzp4umCRNpHgr9P2150LxiQBLAURsAAYsDk7GbFShbi6zPcyTPp6.ObTSzrsPcNQBq_kd3D.xbY",mdrd: "IoC9VJXANDfBVtqt6ejE6zrIK4KwEzQ8N7zfpO824vg-1739797578-1.2.1.1-nJC3OwNv8FtUh5sVi1S4NqkMfYfOCWdWjfvA_R5foIup7rCbDZmUpDrWH6f4xI8s_DcMqTIFEh1TJUIlXeK4wkaebEhpNglwWAas9_XEpbPQf1h7qYYxbl93fgBPWbtYcnYZDqu1wtVp4swZ4ou6AJO_3rxpRplfx3HMjoxocx1IiuMtwbEbzV85N.e4fBB1I2BdOCT8OG2oG21F2e217QljWcY4JJWodwmZPCyF.OKDC2y1j6FvWBqHdgVNRy.gpPEAir93_rkW48Uyl1P.D3cBJYtLLEPel2Vv.dBEKnqg.rEzj7.fI9gz5vSAiuOLMqvpB2IFs7xdIjZUz.oKFYcQq7.7geHql5io.GqhUgIuCHS0RnrIHlYL2Ko6cuod3H83xZliBvGhri7n8KXVb3w3ykuKFT6QLSRd5351RoB1CT0Kki9lbSecycdH9IT_qnur4DHH_T4p.gDZUUsm.aU8CgqrDskH75hILM_a1wYMsY4pLBptIc0HqneArFw8F0Bcb9fGkfP8.R4CnmS0VwLGhSQuyn4qIR1NyJ7nDydl3JsBtfSWgVJftkKLkGbYQsAe1zohPz5rFrgt_u2k80v4Qq69OtKB24ojxM6TCZqWmq9NZ5YtR0GP28yx5Vtm6RiZJUphRQM4zs.i8Q8CEN2ho87OiUJDO102gn0C.8iDEccXzYoCJbGsDkIjQxiCqsrEMbmxig2ESoVufOkFZjOgW45xerA27hpcyebPC0BatYFXkBiRZG2DHKhEnMtw1xhMBJiTYtTLyizEU1sWuN3xNaVJ5yEJGOKAez4naSoh0S6UsgYQgHeBVhPcCYdkuyCly3nB3b.t9wNogitGCdqmHm1hIVu4IjIsAU.S7HI9fRld2TA0_cKPLjdc6C2I4nwl2K8.I1.1J0FYt12u98P3E2PC_wcKtDdv4wRz2f3cQxDOODkZ0WAkapRA73fenth76PnKhmbP8_Fymu_AfnHdwH5rxTM5YLHZimbiG3C72sDZm_6KZEPVlzcmhBuErTxjHhcnz61QRmS3i6JEpcRgGpVZ73NlJZ.XNV8CTZXtnr9Jh6T8sbCnH25yFITzmdqGEwMqt72P_UH6ASxYxalb1h3yMxWtS_T1fIdcpoFvVJP7v5AogRx.Yv6wcXVGCZWmwbR9NdXnc4n6KWRos88UwLNmhpBtT2VLrlJJFrhV39MHGKB3VNEG6HxPAlPgyG7qrIboRaDfK6Xv0h8PoEeC34S5.ksAdbFSIcGPtG5AxRuimCYahNQMGCm7U8hH2CC2PnnYBqPr5GkAVc_jwEwE.FLksiX.QpjEQW2xJlH0pGFm0mQUq8AtYp.AjvjSzZJYjltkY8LQkb7PKAZ2Nw2WU_gR1tMkEoTc7lqx9kVHM4y_M1aWdGrubmTmduwcCKr1EgcYhG7e.M7n0KG7yUL6hM3yr6RhD7KnrTC7TJfOt0G9bGHQvLWHF.73BMNp_A2krlx6NdBQTpk70Lhl8Br2Qd3alqVIM_ZbIKjkZzj9NhkRyVJLxiT02_RDDL5_O0pHaBV.JxGVc9ulTnu18OVV_XNUdP3dbOu6QP_ZARr_K4TtozyIJC3NADlEjTIWKDCJs.Na_WLfIH70Yu9mL1D.lXWsXosfNDhXvFVK6urwD9syteQsp7yqyIZjy2zELSorrneas35yRWRw4RRlCuqP2tZExPnjyGCQdpjONY6VhoNOjWVf2Gx9I..yVcqAaEPEvUt7tEKxMjWSWxQY3pFhraqqKwi.Nw0SBSz7aGSlZjpW.0P1GqJZcb5z4ShacgeQW.iF70TPcSOAw1k.EgE4msxUr1DZ0YSH05Ztw_uipiNbg5mlnva_MIlV1Vd47pW88PmAMjPtlEQzPf2198alqzZpa0VY.APJGVab2qyImJjWkAXTWBM4J7F18uI.2.YU.RRNL4ABHnKozmIdSVtWhoBGcxr0s7gE_ak273TbyQqldGgdvLyfULgq8xjra4NPmRFymSzX2kW95SqBFw"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=9135fe72fdaff88e';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, "\/10000363\/xml?__cf_chl_rt_tk=ljO_RtTNAlU3ns3fce3m6.g_ptvxuYY1rWUjfagHafw-1739797578-1.0.1.1-CfBJKh9shHYPaQ3tBWrH37DjewBCv9w5scqdJkV213w" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>