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: '914a593abe41a3e3',cH: 'QEcPQQuCprUdPiAYqP7fDoex0dd2oNTd4.0cd15Kfy8-1740011012-1.2.1.1-Djm.CJynRshbkmR8XRttE9.OhZtFcbcW2fFnl0_3nJZHwWK_HqRHisnCuiw9IavU',cUPMDTk: "\/search?q=web.&__cf_chl_tk=VMLcbqimhi5kQkPpG.lY2yBIQmqFsELBMdLcU8gPAns-1740011012-1.0.1.1-wGLr0GiAjua.DR.TBDoSKxZlytK5C9ucmaHN4EAoeDU",cFPWv: 'g',cITimeS: '1740011012',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported-browser",fa: "\/search?q=web.&__cf_chl_f_tk=VMLcbqimhi5kQkPpG.lY2yBIQmqFsELBMdLcU8gPAns-1740011012-1.0.1.1-wGLr0GiAjua.DR.TBDoSKxZlytK5C9ucmaHN4EAoeDU",md: "LnRcmVo_qGXMO2zW9zcDaeTGkTfNCqvnqLsdb7YHRSk-1740011012-1.2.1.1-GTguWgI3zjQisCByzMqFI.1xCdLkNTbehhBvUro3M_3vmx0lVCIf3vi1wvvpzkGrehH8ZHFLJph7ctdyTFuQld_xKWmZvR6nfB6RRQ4eNvlFVI4DDEOTrD5yJjK9vmMYy0wOU0u8sAyB65tAGJb6MuAXK.0G1rJA3PRTrDhqAbXs7WdmgW.STD0XEp0bFYCX4.REhsxFDDy.B6o8.Q5wlP5j_JGr2OMh5fcXNOD9ddftKNZ3.ZbXX0DSkuTb7KYPp7snqp_csNTn0AATBFeQfleCRnT5M.XYFxAnUT1DTe3qynbfb4xzTxb1jhhGoMtU2bQyCa8v3bh2AWnTULQ_X8kOcwbbZyQLYKO5fe7q6IUT6FTzXLKMSCXFmKjcbhr5PNdbeUBMWAkTjt4drhbzs51uPKF210CF5WbyOSb4C7Z9BTC9MdK1bwWebU785MJpHM6ZwugMQs7i8zuCwiIDBhk8P.H3VlHgLyj_FUXl3zgQ2Oit5xntMxL6D15cTsBGlMzMqvbNRPZ1CcgX9TOIOgVbDUReKcBdlKIxoNHsAe5SpsT07WZ9RldmPIB8pRApbjQHI73F._nlZCB5j9q0k3IC1F4mr7GIN7BMwk9HhPXSSGe8tSnHH3CmD0I3Ck9dwztuoZ74625TbaOKLZyGMKIcvyrsqKjtOiM0j4F9a_IUENvN.6px7i21SrkgJsWa3DvsXZ5FuuqSAlCKcMknb9tZroHBpqmtaByv2dJUXVxH6NrYntZwoeSgGgbHfj9icpevx_OCQk2WrM88b0hixiS2GwE0qCJr65jwdbhZR19PWvNihUNBTbh9fQsbqFtUZfnUT16HgotQNurLGfQfYE1Y3SIXiFAbibIns8hnB3sjJNmgF.16ApP4jT_OQ6V15YVl9Z6OMKBvKTMJAjKHHvFisCik.jtEK0r3HCRUNJUd6KbXJKpTW1zBA107S8atbQRIhlSvU_X5jAWJR2IdF7e8Jme7liQW_NROBgJB8FoCCDz7oHoChhnCWKUiyyFUB1R7BsRM.Ggx016GALLxEVhuyn_juGqo.XQ0rcO2U186mLPQa9BmkB19wgaWBGl1nWYaYUWupfwmSYLVIZDLLQ2qEf2MjXH87225AIdZm44DvXgLgpYIrOvYP4OkNjaJs66Y7Qr9LMu68YOR4jW5jNmvguVuZ0PrtAU1N2BWXzKQtcSXbBm7W05aLscRp3ol2ubYNNTQZIWPr9rInbD9HsIT80f7Bz99GC_TCQho9Z7GnI6jzuZs8Pxyi8ydJFTF5t7I7u61RBxt2EBSJlNYHv.8_ozKk6PP32.BKLHeIQPwLWKynyow8vIg4K3CCcg4awST5JQU_8o1IfGstJMyazTL.COJSwpfjwVsX6m84ipdV3iXDEV5NILu0vxakteT3X53.VopndT3kWOKyO8I40Dy0Ih7_YS3Dq8O0UArGVzsJ5G4kuQ3RymN6Mgi67Sqj_5vvX08IT0kZx726xz4ZqlcWzC5H8sWmvc2vcTTIKvsmAY93rQTuM.yjb8ncSqAZF4tBfHdrQTMTgiucPZbBFb3HdDK2W2FfmNw7I1qRp2L0UsO.7mHd2wV5w55zWiKvqE2H67O3m.C8d6BTJhJssoWsI9O14frsPeNI83pJn5uvjovmToJdTr.yuzsj63ma6TLKFiLGZ.Vj7Y7vwN1fcKuxHnFItQ1SiqoBUMCPx7Xd1pRnFUaQaqkxGKzyL2eTKGELze6eCm7919a2caGVo8tY4Pk6DGEK7ZcRKiqHBnnYkYiQfMhyKsqwIlhDbxRvbra2CbCsJz2UU4a7e7DwORZ37o2e25K2O3jpI6nZZcMws1lIUIqjqrzItoVwhKYgB2hpSsWib7NKyAxO.VxdQoTE0s7JBe60fchhbgdFTo",mdrd: "sxcoHfEKnxAbXvpSiOrX6IpD.L_HMM86qxncSkbW66s-1740011012-1.2.1.1-DkGeuwXJJw6_l2VJJqhLzwAj7oLnWkJkP4mLuIx32ZmAug4y9y.IJxMFLIhu1ptVZE5_NS9_LhBKU9aUOJwQ7XtAVBAItjM4rMwNRqWuVr5ExCOuUCJql2K6651G2h0Z5OeF_Jdi7wTZQu6n3ZI4_C4yLNYE3c_luWul7ToYpzoZU1XZqp4iBDiAXJthR6sXmyUsdtdZvGv.qquEof1uBfA.VhpObCLmYt7pZwd.sIxgnqWnHMDZ06eRc7wiXtPCaMKKuVN.1.8cH1wD5fgmeJsE9apETy7t3DOJIkPEjxae7Mv7tgHi80k6yvn2Rk1lwHojjrAKZQCHudl0QUIb5vbyYAMEi9ZtAVzXuESNvFUXQKg7TWWoPFYo4MADurD7lqjVd4sGWcvVW5w29aLQRGKwMzT3ecGnUDBxFs0HYlRyQfoJ.phQfbRvj7jDbr.2bSoy5rvsCmcYzYIiLCElTkvKMTAX8KIfWh3hIuSvV1po56mfI7MCi12GQU81EKBwkkMT09XMpyI_nHBjDkPERab3aleuwWmabdOJu7Zw6QJnrlGWl5NVI3Z6Z8jZY.EwFVMpMIskSxHn0ibiFrXixXfTiNvnZwdwpiA5f_CMJlve9KQdNUzsLlizok4ZM9QB9Zie98SEltp.hlj_UB4qYtbyVEqp5c8Rkmsdwkde076Je8_DeDuQKOgQCeHuBHEN6GOfoiVRCzwV2hkaNtSu5Nvwx.Rtndy8qBsBGsF4g0jO4WlOJijVfT7IrZ6Bd.AnF4CPnajgKIdUZyd.t45l4I.tsdgu.wd6yYfOuKXt3tl.OMNwYGZtvXh.dlPf43kc49MOtiuPerzS6JG7O8_5jgOc6nM1AcCIOlRNS_Ab3FtpPuQqmG1gF09ZByVevzSSg300CkvLKXTAKo1tikhNdxIRm2ET6QOFtiKP8cmrirwTSeiV6VjUKgKJphWMVn9cTbXsIpCtuMF1fEc08KK8I6jI5HzWYhl5MHIil8J.4CFcVWLhTjpAlfy3pGMma7kiUu6KAU9C5wLCI3GPAovzarwu2TVQwdwJYoOMstkWmro9b72xNmj3rXEi8XLSWpQYbgb8kPmxOBp.1hK.Z1KSVnpUJeosY33SFxCWHtim97cMQDgHDT4h.UyN3kfX7WK.jUrHlqx1Vz7A3Qeg3hiHoF9CL1tPXBeW0u3SB5H5ybMRn9MuNc4V.fnNO7ireLL_wbhu_WxzhkVBco561we8hId7Qk5cG_Obt8KBTR9iSr6ynYKBBuPymoSpcyOKwQnZe2WxR3yO2N.6_DQEwqT2MyR6LIqslLGmLjM529uo91YRQcjy87sh2PNAeZl5Cb662vKBnUtE0_iQKFv2KcI08WSxt38O1bZW.Fsqy6v2q4pAaK_ZguHNX2TkkH9pQhfKQqBisU36nRZ1VZ63bZ.ju7.Pis4VyqDBkg7Uf3tqXKnrSDx3RQeGWqj.Y6v5gBCrvMT41Rr8k4B.0daKZvxqIOSj.ne1SP2PnCxUyjhiqY2rRv.akPrHize9MX4f3nn1eWSLgZPXqJ.kiQpvc8bBSv9ZXyjq50NHOwoWaCjMqindqwEAEyitGDhO_1fK9kYagABjBTkwO5SqDMR_WC117EIO6gaFrcZK6QzogVc.rTg66nXHOoCZJ4Kmn0OQBfoZu2z5y68T_uT2dqIujkKTsKL1ggVxXRVgXhwejhTd1LCnVMc7X0PpnxUKsRUMrGLQ9wX6SGUsphyKLun.VjTURlgtHcwglJkGnfyd_D3dX6sv4pM2nV5JDn2Sx_k95fJzEqY8IaAia5z2QoYw_Y0LE9N8XMabF7_89VAFnkfOQCN12leXR5G6opt4XF6CKjU8KEAki7hjiCr3N6vcx3WIyNSln2XKpHbXuDSbyblkz8Ns_5w.1qK9.7I5dSkjc1yYgRkkFFbgRCkXXQiKlVnsn9zwO3yn4HnnXvDNOXAsLaWtOyzEI5oT3eIpNXrthWRj"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=914a593abe41a3e3';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, "\/search?q=web.&__cf_chl_rt_tk=VMLcbqimhi5kQkPpG.lY2yBIQmqFsELBMdLcU8gPAns-1740011012-1.0.1.1-wGLr0GiAjua.DR.TBDoSKxZlytK5C9ucmaHN4EAoeDU" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>