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: '91357dcc79264983',cH: 'e36LXorcir5ixJtM6e1WWLoY_mHzWyp_D8yYeQzcRz0-1739792309-1.2.1.1-aTdJS36sqX8FpneFII0NyYvc3EpenKVHCpRKeB_M7WElh0kVhVSLQvkt9TNbMPMj',cUPMDTk: "\/10008087\/xml?__cf_chl_tk=rxBPBnOdDTN1EbKWcsHb7K2brvnFb9PmnjpDVzp4gP0-1739792309-1.0.1.1-ur3a_z5RDgFJjsWdCTxosUElzaB.N8bI3scCgpRqad8",cFPWv: 'b',cITimeS: '1739792309',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/10008087\/xml?__cf_chl_f_tk=rxBPBnOdDTN1EbKWcsHb7K2brvnFb9PmnjpDVzp4gP0-1739792309-1.0.1.1-ur3a_z5RDgFJjsWdCTxosUElzaB.N8bI3scCgpRqad8",md: "KbhtNZYVt_FvRoUsAgJdNxb_rJ0N1XRtCG6B0MQKV.k-1739792309-1.2.1.1-Dir2Tde8Jk0HftaLsieIj24R.y0_5vA26sFgd3B.TgSowuQD.Y7YnC30whzwtED8NFKA.FFg7.gotiOZYgDEKDkScvAKax1bftlxtceq080PUjJ1CPWuGxZngUOi9AdMaOS9r_IiwJmqhuYWbwG7gq4Os8g75dyImsDB0ZlT8bpxXYPXzxnjrsKYEx2Bj4UUUHoe177A0Okpvfi_YRxVL9.NFs2KFvP4En8rh.SZXOeg5paUeVncOGwXjtbp5pPVjmCdNN4R35W5DikT.JBasw772_rsV8FAIxj8gtPYE0d2DHl04UoUVjPQjXpixw4DFEbDnas6TwCiPqV8wrRltMkzYmlOLIqBFouCFGrCuyfYu4udZuDOrkgtd9aKU6W4QiTIoqqgEfpRdhmqhBL2RzpA8EYM1qYVyityiDnmNJ7jT7KrC2i6.j3.UVCNdvf_egwx7UJG6NsCMAhbwcR23hqL17BtiqUfI5iWC1E0DhuHttDMk835OWmLnl9nNyIg3bpM3DN6Cg5axVu0vAyzo0Jv9ky_zI3SQ1xX6jMOKGYo0A9Df4Gc2.LDp0RvVvfWadCJ_rpIJ_uYoHWk34654RhfnF5PqDeOVHcirbL6cs8ev8v1FrGrzm4GWX3DzPyz0guXwLeICnDbnTHtWPsVfpJGvmly3bZGqal2dxO4JTMbbb4_7Tj7Csq1HAXZc1G8GPRc_IZ1lwFO41zxOz9P0yRSaHSHhgH7a8ceZy2ntcSBV7t2Q2nzAIgc_G2C_ClQnWNx4TKsIlmU7lpmfa880opRz3yGeHL_DuhUgbMX4KrqmftzjQJzvSSBcLSTHO1B7Q0j8D6lJlKWJO4Jyy4gax1yuFQdWMhltpIA2ABx8HhaxmeN2Y6mOGMbDjpwPKVOP5jvvjLGFXhiDBOBzTBRtQC7TQOqv7umOO4sh8bAW8KSuzxhgR5l7K2Zwb6JS7pgMQfqOVXpMNKT0Ho8uFnlO.m2olqVG53T1IaNxge86bbdMG1EmH2CRLf55TRU6QJzePzk48V8VE9GZ8fdNqwdyVWd2nyq._72X.NGjqgIK1nF.3ZidOXCPevZ33VLjLTek7O81Mfh.qkFTN6KIBD2S3o6p1k1X31rSFSQBHKsb7ZIKYHAzF7hTlb2UR2rpuMu5i8BvVZIbksC_1Bbpzd26T0Pb6VeJY4WzFZhTchknfgyW9sbd9j0EoQxRiLQCSA86uQQV4mHCNVYPrHCeznmuNYFnmo3NJOaQxbCOEtEsNVOo5zaBOy0fwDtNT7ymQFSMxZjONx1y2zNfSgT93SIO8faXspe6UGZReHOqk0vrvrhIdXESV5rfYRIUTNADhdHRCMpMPN5MkxFLQ75hhSKh26Sqa8n6n0WbSGDg6lcYtFnIYM.D28LCwv6rYGLeICrkJk7b6zjHtLgV9_cweTXAlNSq_23FSbTs63_itEWbu_iTL938vcy3oUsOd14I1PQ8MAyxDwW1uk_B4claFaVQRsGKo162UBWN2a6Mvs6syikrd_iSp4woFFA5eR5nJCySnNp85Q69OmJS.ILlN8zwmVw9ygAPvgwr8nGBepxrOr5BBFcNT2KYAbbYBM8S.6qNvPRnfRdHSRWxLG5m7zONmsaxTicUOp9ms4wmV7dQGUSakz8NS1ne_s5jLN_TLN2PGMNJ0j.8evxX1q_tJ4xF6dTNQ92mOO9c11z6upt4DS70Lmjz9346jL4ynrRIq0h3oV0.1TpDOKk9T01UOPF2cpHQLXi8E124pj2VBmxsS3d6A_5xmtrLfY9vaqFYkArLQdQ.VlDqZteDTgXytFZC6qDVPmtXaM_AZP2e.LH6bCxW2XOfRkpaKpcgNZewQKEheXAOSJtuoSqjQ6xAqayHlDc.eIKvjAqLYDOjvzKn4E",mdrd: "47.SIiH43fvYFmeTmRGOqOOUA5SbzspkZdDn.Hy1zXk-1739792309-1.2.1.1-MW9iOA2xatKnC0H0j07g.122ZhyYNrfywkWnWlXD8ZHdzPmXDlkvygRew2lOmokpwYLpDb1K0Vkvr2qVpIUMLNj6y8gvdel7gnKwn42GxVDWy8xiw5e.lN1aJRHVR2CEhZ2AGdkGS0TYk.eBeMjecvT8sl_058ly9nbRdFLgBbX1ZP3SCi6ZKZZ.xgqw.Uz407q2s1a3UVLftEKZCdrcE5TG.h.AdnYGXrBw4NqLUkpcrNCMUoUaq4lNQI_S4JCemSxN6MWQyj07mWWxbFViHXNYvbLkMURopKf3zYKbUIzhqeKB2.K2m1C9ja7tQ9RchF7LUPYuETzaMvQE6o_IwZcrRqFcpRJR6h_nYoUDNJu1.RPYlZtV_X0tgJ_mIQvI2pa1GqUxzsZXDD.f.q9qX5MAEd2PkicjwgHvzMCK.3xO_WPXKgH8o9qvvGerWRJ70UBAtJR6vmDHoGSI73HueAKiu2Bwlrfomd7jAts.QmpHp4IFTckHUWxh_Z7Y_K5notY6_7JMJnn00KlVOgzG0yjGc8qDArX_hH_.NEs5I3.lO24h0BwQcvNBLVA_9M8alyGVqhMLbrGx.BXkeZJt_EI6NLGrgYHAIcYz5GmpPA9FkT9gj.mfRk3wfciH7Xg4fa0tZe7tGkCY8IQ14hUC_kODBPZu37GIGxCOJR.FJTOrxUqnURJ6w.RfOKGnqWAGmUFULsLxCEMvoRbjiUPLRfD83Y3e1nG_ryZTZR3pKGeLipLuG9GZRjwmch3bSOZesWoKagBXFEIP5YhxL6habmBizFQmOQh2GS2XNET1UMBDU11HipQ9yqEWia8Vl_vHnNpHy2JJ5mRlVcl9ju1tN3TBJo9D2BH8C71QB2i0uHkfwxsii7b6aD1yv1ItkPgFzDwuVnBO_Cp9kJVM0OG2nfG_atDhlrWq3vKVuc6v9_5hWgCtJqn5uu0Rn6Ff3lI_aYOJHNsw.sMK4XIcpI9ecBF0qd9BzfM1V.GZXMyrpxOtAX5r_nEyrji4g2gp9ixmcxfbY8v5.UkHR1pLtFNPF7fdmSQQK0grnYGhyrkUQqs9fsmNYY8dqB3kxNXJAu8PMHOCXLC1ciTiZ2sb6BG.Ubhb4UAYClqQPaeEpTn6hxBOY9JUy9VqPeI4r7NGHpjrUjTZsH_cpnO0aaGq.U53CEcilca6p0HFwaW9zwDLmavhgO51SZGaay11atsxUgirBkM3HOiyGHLNSPm30kXGtXTKyjGtvp.TZo9T7zj847AfaI26NHPrJt3iHRj.blo2bCnTKdFA1gBOmYFEJSXMPfdONQ5jkZvQ1vz1bANYonDUORAMXeL6seIVwy7kq4jrPiVddpGmHpQK2_qqU5NfLUKdkJhFOZrWL8UUPXZvfrq9Wp5ZPayBalrrAgzHfGEk1JF.E2ONc6UVe_DxcwVJ7PJxrOL7YCA1AxBF1Kl4sL2OnO5Vh_MUALVmACto7vmrzccI.wQcKP9ug1FhI7Z7sQJjwksXMVgrrIpv8pNZqJzy3vd5KiWqPWt6vGY6K0MOACIzJifuKTU11IO1EhO5._aijx.FJAiwZC0LPCB3z9iQ59udrE9AHQwYyEVcw3H2oULRr3a.D4VsI4RQcrDchjJbgI8I8vPqEeWD0PMBJwC5e9HkjlWvAgS0wsb0ccDF3BZlEEAawmLuNWXbHAQCb05UjFCiDLxush0eyLfdLEEsk8xDy6n778z9cSDWV7rWdkIZNelgOu4eUTcW9qEOwfkU1rOED7PeM_.BIdEeUFK_UjRjveJhGIAsgOqARrVfT.78RNEXhM88r6P0lCiNBUQ04B6A3imDK9SWmcLLc5fKJaqTXlmPL1ZQWCMxUXRUWhJxrINxpb3v208Lb8j10pBeotksJgOOW06P_0s.p870Vq1WRp8dz9GRdovgWDu695jpaQ2R8gMCup2Eu0c.UlfDhxgpB3sRUZt_2GW4BXL0EWDnNmuIarBRFjWGfMREQLxpVhrfVGLMBe2SHnaDng"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=91357dcc79264983';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, "\/10008087\/xml?__cf_chl_rt_tk=rxBPBnOdDTN1EbKWcsHb7K2brvnFb9PmnjpDVzp4gP0-1739792309-1.0.1.1-ur3a_z5RDgFJjsWdCTxosUElzaB.N8bI3scCgpRqad8" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>