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="390"></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: "scholars.cityu.edu.hk",cType: 'managed',cRay: '8e911818d934ce8b',cH: '5zywi6A9h0n1f6NVpQhez9fTnb3UDgai_MYTdN6XG0E-1732699769-1.2.1.1-RDNYivgT1R_kR.NQtUxwthN04qejYyl00sMQNdLR.cOxk.jaGaiGtZJLvEtQ4qzE',cUPMDTk: "\/en\/concepts\/refinement.html?conceptIds=195892868&__cf_chl_tk=tdJ8Q1XL.NQfVzRg_hUpOiKkd1cnGBUxSPcEgcikWko-1732699769-1.0.1.1-k.G.glN9cozd2GV3RigK7tqHZ6RiLbfMJa.dfVeLULI",cFPWv: 'b',cITimeS: '1732699769',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/en\/concepts\/refinement.html?conceptIds=195892868&__cf_chl_f_tk=tdJ8Q1XL.NQfVzRg_hUpOiKkd1cnGBUxSPcEgcikWko-1732699769-1.0.1.1-k.G.glN9cozd2GV3RigK7tqHZ6RiLbfMJa.dfVeLULI",md: "YIq_W_fhfstEm7wFa_cwVnAWsxee5eAC.zj4s5xQxHU-1732699769-1.2.1.1-Ma7qW4Tf_9mTklL_Uz4H7.AfsEOf4SMiulhswVVjPWJTb.ruWX3tYl6LdMSmRXemtZh_.WRXv2gzLRN7NGXlld2xqnvhfF6p7Yio016zxZm4o9mWgm1GMN9yFk9Aks2929UF_cWBo9nOjB9cvDNrkoTYlbGmjDz9Cn71oQMF7YI8r0zDDZHIKGKj5hVa3jX6ts91xYjICw3hAl3Am2lWnjrUB03hEFdblQNGEvlOik1_sB7AUM8skypRQFojVwmJN5KuxkGamlkXhRNf4.BRsOGztKo4s2yXun0a4n2lpvcmLIYULbrv69od5oyhRjRVrOCuki68GGveybGfSI1EJiFQCdUV1fQFAR6bAeR4zFWHByXMmhFEml6YlJ4tx3j614ti16hHGrYJJ6mAlD1Mw4lvrUAqC5rS2LUiVnQ4blbzYAhv0Fzb5_2.DWSvW04OgM4JDu9eEAefNkpSwoyBvkdI2x5FDG6vw6GVv2w5bsl0HBYzFaR7yk9qWBTDtqdhaLsxJhKuYx1SQgNNiDi9ZqXmhPYCTTQ8hxOjxSozBeJDdFCa36tL2LpR5Wc9Zeflen6I1ulDv40U3TR8Qoaxo2DwhkHSKyKZZ62B4thWLYRxS6bakS_53x.A4CGWxzVBi6UjDAZo3GE5qgAnALmbz3C163cFx1aK3Nz9Zmz7UZjqcHgOVZ_FTsqiKqsrEnPFQaAekeW0ETNbmT3G1hmV8PuaAdOQupzcLq2ZkLvKFg7GsXMZxwsYcL258KZbsDVFWALVqmJqVwYCZPxLxqD3yzlZaJSQVDyd82NvrZuo6yWOSpjYw.VDBY9qb8w.Q2cR39lZiCtRPOXXmAfqqkexFKpqcxXERMYyo4dlwX8xkyeg8YW66GdKuPBKGrbDpcQRdQT1yv_eYA7vTEWSgJGo2kD.SqIeuhF.o83yfcIzsVZZLEYaDXqTt7RLlKac64ldnNRWkKjmr8vYNwxbIBqmmN61kobrmmJhGaR.Xn56lNR72Mrin5Whm9zH4Ge6dkHRxOSMA2Rn7YgB_c2l.6vGw35T_pBWSomgfOEolbEDKm_u1qbfiq_BTF8EXJGuXtl5C8aar.27dbZdoendQLdNID34mfZIuSjWdHt7SrdPGsx4xSV1ijtklv70STeaeqCLbClGRheCS5QtUAMBCte_HbiwR71QJYprLRSdyo9wPQuTOYf0TfhIulIW2H9B_DAMxhy1NZDACZWRfDH4OzjyIDr21hhw9G8U0HyH.wXGdk1dEnxv1khurtV3PMFCSqXNQuZRuThoodLGiaf_isJ1sTHn6DGQebrNgqsB5ZAjlcfZCli0el.Mo06xPOGen1IPXqxjntMG1XJsTRqK0_l9lsfteSQYb6ufU8FtjZYYBW7vMbUnvxQxyoRM2b_9pjX0amwoBZOi9PobDu4c2302qW9zHHRdBPfpzaamI1WQdEv6W9RRUZdATxUpueZp0feH4FqSNLGa6vy4eIMQ2utHjBB_lIK1UcwvtMRzXXFuQfcGsgosjMe4EVect_hytwGGrpkJg4N0tGEFxn358hpkYOvj2lkFSi2RZI93dWsJ0pPsb1.p1IAHSVYj4EK34Iu8jl54L3oPIwvR5WW4Xcu4B8H0orGAUsdOYQOGT0OgX362FVicW0iSsgJ2fgElShiHnmVigxtWdorcHLhPAcoUAynBk1fJeUu07dsSRDaZ0p9zGtBN7rVmj9Xymo80zVsZVObN4hLeRjA3wXUpBp9Kt8afNO_FiRYmj20YyPDNx3hB3uFIrB39WmBry8hp.rS7l9TyARL28EXEZOpMyd1mo0oJGOjL5Y7To0isoSIt_oPt_Xq57y1GMmog1bSY.wtNbLPQ..qcP3ExoymjeEHHufkRHfMsgA.n8jzJmOQ86RCTmx3TVR_QrLRF1tNXT5VCnVGkOChRPfYQUjBYefB4AKs3ozf95UwCXNteYe4w1tLqPgiFnXfpxeyoVQIiHYpgxWIlJ8_ih5YNe8G9mY3CTavvF_d5CQliHdahn5AHjnl6P1isei4MI4xAKhWJHIlwtFPzOQjpDQPB0nGrB4WtRvR8VyWnMsEE2sJ_An22Fz0ivOEpCNSY.LzaRfXPrGb7ouWkDUuDZJdNymd5.Nj59Ku1uCcMJQXuLeFMXAid.l0etmbF5rM8bm.4nPtVYZwgQSOMyLIc7eHTARcsGTwZNX0vTzBxC6rWHRtwfZNFerLQ9PsIBcK8pxUMvp0_1IB8Y00wWf1RCf3ea1eaP_LwCvfG_pNcRaaNpvhwNtbQg0oTM7N5IEyTqX_qqqLWy.NvHxWot2OHh8q5Druhfud2WKFIEwJlbo6fZsyN9nNybNbhU9WVQNr8lRe7gtbLyWQGAzF6IAfhdWv44zVMxrK0rAVUKS.xEg7oQ7DydzqD9ek3AZcSPEvfYAszLO.9AJM9OS9MfjGm503fPMqnymzYBnxH5GihVyaTpiV901.ZhB7PnBJrmRN__SLERC8Nl9l3o9k.lswjsgpJZsGunxoxf7e2Sg6KxqSM_qhhsjboT9qKkxzcDoXaYZ5ly7NZFn_66_AuL70FxRmvL4Wbz5WfXkuEJoLOTgPYQeTqTQk5K0UNHoCt0lm3zxkbpo2GdcfrMf5_wb2Kfg9umaTqqajm5fJbwVLpcEZmOVUXNexQDFuMt4W3bfjgKZl_xstxwcvvPQslfc9pWxCjFGF9ViGy90y9LNpZE_YkFx6..CdlbyzBjDfqUqR8md8rEpJFCA8ih4NyoHFwy1D1IO2yAJ5S9PiT3bidAWT6IfOL3Lcn5VghuQiC9LV0tHsvfVd0TcRC060sroc3zG1wQbZ8QU.eyYLc8lgLEYyizh4ASUxcDahAR3V5TOCE3sXIgzFSk2yUbZskfgwYj1KoWX8I.KTsuCjefpCNpjv2Sy_ozrgHGmay8KLHr0b2NgtSfK2N1L38Lf7fl19E5odcRY2N3mevJAVpjd0K2CbJ55w0GJ09eNkCPt5RLgGOylz4P3hixG7VMSCxBPBxxaPukSOc6SdzawoD7ZEIV31nbX4Ga0R3AwEvs48Xa9CXQuil0F7Abrts",mdrd: "_Zrv3rshsTPWsvmbWvL8D7cCYGG1oXhmzbU5i6lqPYk-1732699769-1.2.1.1-Nhagif5jsar5gyrgT5q_LKzvyoFiYDWdfuRL5lXlrXmXfii.iwaL2mDJSqRWTOyP6h.X9Es7CvBEi5HuuCPwllq6FR5sen853lp1by1qtiSBNA5_OTlEQTR16kgRndwh.d05gq_PQkkEGl4JHnWKkFg5gHv3de44JkBli3glvqbzIHjIBwpCyirYWW7HaMtwNWoyD7ogSS7vN6JpcGb98P0ripUqbF2NVkXVYBKmF4FhgkYBT3XNMQbsonMsjKXSbE4F1ArmWLIZ1mBRwy.2ggJpLkAySx3uxzBsD8ePOgoLG6ndvPtwvyqfKl5kcgU2_Cl8G73rkpzbwz80ap_V3kriZ7NGw0BYNBlal40UeC_aUYNLLZBYeq_qQ3q6Opqda2dw6HdsUKlkNX15d0vRY2RIWJGD1stAV731kH2j8R9X6_GAyARAzD.xE9Iz9KCKkU6yH2j_9bsDT4yu_PDNAL3IMLM4xvCV6Pr5gGeElpK_Wp1Qb7tkR3fJjvPJ2DHA4nFmkxeU7gzjzlEiHlW7K7UDGPt0_QghAEtykwO7EbeZWZlsla_6q2zaJ0C5OgOk1_028U0aE2ZlIViJ5k6lpaxi3DdvtUo5GO3ohfnyXQedT_PeAWUyUho70NTrUN_x01auLzi4JzjJLJ3172IBoYRtscEuOQaOmgk7iRbMjJzKXtFLI1nWSP7f24ooEfmniPkWdgu4cOgLv.EI0oMftNxGDmXvV2c1WQFc_wbndlC7._N2V3jSKVckDzNKPZjjO1gwOaYOBWu7MM9VkHUqxIKhMDQsi4sgyIoGFsEF853kn137Mpd6rmyAcOqJsgM0YX7QxtRBDBNawSwIfHm2PgOSmJH6zv13_6YVTGJb2ZsfWu1CaivT0TXz.I6Yn_kxGwFqSvuQ7MrV90HlZ5LPH6_KpKm4N.0w0eOYWJD5GRrWhUb3039.K_KQQgXONWWY6i5ib5BKsBsaV0IiG0Elaluh2YLTW90RLTXLJuY2zAzMZd6YOTfHdyw1nQhu4ZZ1JyRctsW7KwU_kNfCLdHbviIZJUgK6BzDgar20OYgnV3Hpdxl95.jhGibYYPr0enPYH4645mBRdBazByqASBFqYPxKTHpS1dFh24BWI8vFXBKnI0TeqErHU3Bl_UeAA3MU8dqyRvN7VMUp84lJFcyjz9k0J9cvBzXUL.T7qC31l8k2nDBwKsXi9S8TCFMVGHYzOZNWJ3zfSd8DIU_6WlPQoOf_O2QgYyrC0MOxUG3Q8TrNKWgavUX2njt8Cv7HhiyXDz7d1o6oXQu6HUt2_1P4V07g1Lk8Zn.zQuDbxoO3EZeJ3OAjpRk4I1A12amwH1LoeVGqbhbiOJK9T7_MTT4lEBM2ldf750hNM77BRefcGOHofhuwtZ.hAYm9Yx0fCKlaT_Boi98l6MT5jMwMN04mzu19Dv9Nyz9p..klxLU.53IMuW9Uz8bKYTqZnebw_KEMr5jWs96j2cq34NaVK07A.SRwOxP.hGQt_.88rWwleW9H3BLLOFOEwRUohGVCBBpSCHhjZIZD2M8DibFtgejERaFSG9YnCNSnej6zcFvq0zHawY8m8Ehh3Ah4wGHUyYGu9gap8INFXI2EcptFapCcwhGbzhqJFFejMSGczmMPOIMywlHIhdAwRwggSPupEGDr2rEp1zCrjIjsju2Q2g8prnBiooCQqezWdePx0HMmiyMEetSZTB5xTaSkwei1HdJC7__mYDCDSCJ.tu2nV5kGr.SWwyOAhfGyWtxoiSg901O5cmx_Ig8WiOgy2YMvGaE7AsAdCj8_ZxswONVQsHNwUPQbgQ_2HN2iq63qB7OYnOzocDLeQllqcJyhw.qsNA9NnQRhI1Y0ykTcSClHy3tWBeL2QW2_6._HtvZ6KBiICTysP.5xiYYYrUhJ0jzZfLEqtBITsOb8xWWgHEZjZtlQ8qk_tFQ20QdBeW._tN6pGPpLJb64GgTfecYbKie9aIw"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=8e911818d934ce8b';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, "\/en\/concepts\/refinement.html?conceptIds=195892868&__cf_chl_rt_tk=tdJ8Q1XL.NQfVzRg_hUpOiKkd1cnGBUxSPcEgcikWko-1732699769-1.0.1.1-k.G.glN9cozd2GV3RigK7tqHZ6RiLbfMJa.dfVeLULI" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>