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: '91350805fcacf8ca',cH: '6yJ3DK4f76cMJNBNHEM2QkeidKGucVP2JY_BRGb.2Ag-1739787485-1.2.1.1-I9tQXldOGShnv17mMRXFfE0WW6xwNm4XxbcdJuvnz.Bk1nVXWxi3ONduql7qgKCd',cUPMDTk: "\/abstracts\/search?q=indefinite%20blocking&__cf_chl_tk=ggEuiL.kg0VYjbXziwZ_a1tUi3K6Y5pIm4xOYE8al4A-1739787485-1.0.1.1-QrerzShjgzZUDKbUz4mujPAT8AxeWfVaiiWqVaq9zvc",cFPWv: 'b',cITimeS: '1739787485',cTTimeMs: '1000',cMTimeMs: '120000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/abstracts\/search?q=indefinite%20blocking&__cf_chl_f_tk=ggEuiL.kg0VYjbXziwZ_a1tUi3K6Y5pIm4xOYE8al4A-1739787485-1.0.1.1-QrerzShjgzZUDKbUz4mujPAT8AxeWfVaiiWqVaq9zvc",md: "yWc_1Rxa0Z5gjFSAQFgnqXjgvRT98AFa.p1xX0R_dbA-1739787485-1.2.1.1-XPvWgRWZDO7oCo9KPon8ipxkP4kEmTzP.hwgQVR4J3FbZ2PpEpYfYnSeu84b3R3xxiLxQ.mzAYrcXGJoLG1_kMDhnHGfFqECauloXX6AVYPvUL_YFbT5JYP3HVhK1tH1JqliOhh4xYn2WiXMxygqA5x7p3sHZnJyaiB5Ngq87KiGzzPkjRkF_KNTIx6gUeXvZW_0lbQD0380unZdTlxz2bSQSqh6.yjxi9Ha0pHrTq7yho8GDcgLrzjnYooWtnwFVHa4moYWqbf0hPpKY_7a78SJje.YqtQd8yZgWEHxzAeOQsJ.viR08k2aHlkZmEb2Fpw6YN6NepXNT_niOdlUcRsmFSUbodkEuPBcojbOfkBZBewWwWcAXJ5h6AV5DSQ1NFRufkV2SXsZYS0pc.r2vXXj64KN_uoorFvXv_hoUl37rpIi.tC3jwpGPgTpapRhSZSijRw6pwjGYihT2lq7eR2Eoz6wXWmhm1SL9bNV9DQtaFRQXtHu25zeJovLZX4elygRqJPOOgJVzf6o5Rjrs_xZBI7XlpLidHidp41aKrs2qqFqqkrLhQHwHHGsRMWzJNSXXxVXPusF8aMangpzkmA4G5rLB5o3ZIY5Mfn.6YP3M2Ovnw4Tba.Crd6lvKiX9GNCxo6FMUB_IFrAsC.M2X.HOWoX7_JvHJ_a_kLvwv7xn2R3gZj1Hrldb096IsBb2l.Lua5PWNXvGyQTQ3yrPsuVunJejq_zU.p4zod1u1wIXuZjRgOtUB0UlYhTyeIAv80ahOCEk9KMQ14J3kGkwbDdV69HO7uF5ODTPG_sxOtdO_Mvn6y.Ohk8LqE4CIpJkjOH3DVQ3aJl4Acheiq5rwM7tC08jTWckRwAUDu65i_cFWcfX5bYoJcnM5EGhZLGF4AiZbgpCP5E4QwnyLTovEX5XWp8ujemsJfHFIICXTTExO1jfuwP8cxFKOQSXq5623r72d.tEF1x0HnRTSggAv06x5lcbrtXFMJvt4TrjV2g_afJ1jF.AvY1.f8WtPsXZDAew3K4xiUmuuMlVkVzmbw5TJgcMTzL8pGKa3prOeothY7eKsCjeYQumyXkl7JOIynPEVCHsf2kqYkbW5p4R3NT8X6CphlW5YQKY9Y26Zy8XJEIPXkQ9IDKIrxqI2kI1pQlUKAKn5.jbX4VC8BxD7sz4mokPgGGCit_QRwmBmuokccirMlfGIKxwXhW..V9eNfxedWunKHdmjjf292yF_ZXuAPkLrwfcCQ9BBNNETJMAds0x2ZmDoV3MecGYM_tQrtu6XWrT5PXcMfQ0gf7PHg4PiPtQIHQCb7LLhdsALzZNQVA1.W1hIhYYzP3FMfO_1ihdCTJ14vnnGCfhBo8j1TG9.CgC16frbTHtBLLu_z2QxycAC4acxs2LNEbdc8Rwd58F2TZezvY.mU7hzTDgr2a3aiR3qpHcRtDeT371VGb69HmIU2XDFyjkf_SNzdv3vBL5PyFPw2.2KmZBZ6oZaZRwkGahH87fQdkB5omybmWyEfDYqlTVD8zq0CfhiXGuD.W4ob2MvTNDhy4VD_RNlQOBFR3L.iVQu0r41Rt0oXRBtgpRiu.TvtoVgr2x64O1qxSaDaBt4lfz1OSQPFsfAfsrvjbHnCtkimkuIpOGxhsZezptQKGoVJoKDqU8W7sD.Bv6a3CwXGWzepjX1RGiRyZKMmtJGMF05qV27P2RsxmwVXsDxfIVsFPCcZOmlgVU7jxbkYhJkpY2sg22PucS8QA2mY4A.zrAQ_e9J.YbmaRm59b4As5kC7wM80Vd7NdqANIFk2YIltOT.__4RzOTyLaHepSNiUkrHNj9KEsb6Kg62RYq8c_LmZoGdLbHxbYYPE41U_m2pS9vJydaG4hNCsET..XZMzBqeUN5IcAx7VIP45z.ij_0FuaDe_6rIlWmihra74eppaTntBNPmr.D3FbSwi9L50O3lCXuwOyVAIVGqTFXAZNwXX2Ut3uKqYZ",mdrd: "_baob1r2XhQYelIlcHKHEC.st2IE2OtW7oJscFqOPe4-1739787485-1.2.1.1-fj0NwA4Pthe_aZo6t88BdlEbmh0jNWtwwBNs65PFleTAEFSn6ck8_bHbkkGN8Qk3bAB8.muHZzf5Cs4FjsBbbtRTlDzZ1BX_oV9QU_K.CQduzsmjd5Eimv5D7zMSbD9ypf5orZoLjI5KZtW1Rv39.K62FAw6RoCdHK5Xv6zjwtFN.8P8bPfm6fh79jxHnEUZgv0PiN2xAgcQGSzObX7sCAKqNkqF9tiEPEyCajp7BY3q.CGmHVwlaH1elAvjRSuH2v6kc9Qc4.ZIx4CAPkOPkkCdAyeR_gv2phdEylfctqV8yLgcpa15CQbmHm38w5U3D_f7KL_hGpMQcuPP0Yesl3Zbv_3vFOPrhbqNZFpJg1x5UWZdL3ze36q6TOA.3PAVzQ8CbI3tq0FhouS5n888AD_ClKhC1Jdh4oKfCTcOS9kAWXXIv_worI_ZeijhQgMHZr7A9ykv8E77Zt7HRtPX4CBl7C96FsqcS1D.3WwTn7zRAgT7KCIc25kV0DkwiJujKCtr3H6LAwutTLzXJeQ7ZnNz6fuOhNsEqrXvQs13KKse2OSGLwuii0PxfENDz_6nxB7iKiP2ObfEKQsUaBczhrR3BsQNJFNQ6_FyTzOm5Ob8PuqG0yNXFoPLheLIuWnpV3ofGhv5JT_NewzeB8E_zRGKtiGwswZuKfZQekpH2hFBG6mGP5YHjrEOZ8kNUQvDYqlGW787jY8_jaG.jXuDSLakL5ikYAuj6LlG.rc2kCLhousUc.1ffR3.OpNGF5jfXtxI4vKXVLiwMXd7qbG_vakHXAfSOa_BOpsu0uEHBsMEAKML2rWs6dUv2eNb_afva12ZblDmigMDr_InQ36qY9XmC.FpTkFLeuClIV.VJGmFZ31vbTBJZfWjoCw7sjvNZkvcwNrSb7AI5riSwu_fZnPluQQvK1OOTX7DG51Uwf0T1YHwYqvsdjqG4quEUQi3vluOvcTof8LRtbB1C.RQfkAt93H15Z8xcANvI2uFx_bbgNhszMUavVThxtTp5.f_t7TP18kkRGKmGzz6r4MQ1uCcNJkjhDAA2PrxXA9tHluy5us7zJSZTUp9HVJTEW3GpJa8nK8LCFi2y5uZ_KO6CBy8YsUUGAynF53xEIjm0.TjnZk1nAXVFcIK2gg1o_b2x.4Feei9qZGb8vZmBgpVsORCXd7TROgD8cL18U8W.KS5UofXW2JJ1rxim3dA300cTitlo9yJ1EhSo0tUnlJoKH6ueRN5IvApjTNN9HTRlA9owAOM.94Gh0MbpxcK.LCGbSYdHjVXtUGbwjUSw7xxTxLWAvtN84gPyNeHezr0JOHMJHWoBkWN71HbsCRRyxfE3qda8CnP3MDzZrUzx3oOtSB4dbXmQ5Ql0GZfWfcWYb9zyO7kcKE0f8ADxSufXBfIleNoN_azw0oS83AOQzppE.DVt8CHgQBnmdni6b6QMTxxGh9Ouk55YAW1pDjz.VbZM3CFv1lZL3GSqwGpwbIeb02qu8ColF_VwePTcNKM2ZW1hDGjiokroMNKCad.6tZbleBsYddbRJwLXyxdDwFY2_0S.txWmWgKoXHGZWTtoKiMz3u4RRWB2mS_C535pHELkZFOon8uUrgHCy4pBIEVo1KflxCJvrHEynCVz3fJF_hCbZr0kP5E.ncoPtMsVYHS3O_Qk8FbUngXzggpPCnzSnJTfjg0Xnqs.lyZITdBSxWEsGIvB0kSJSiXiJj5lRK5IFkYEPV1tJJJoLen1Nnt1lVF1qMld_gGX3v4AWbOYKXlO3CguQYhQwgnwRyWXbgziuU.WEVFlLgGfNq94nATB6SwZBuX8jx1a821GyZsBBWMRAyTnm9orE2ThK8Aqpk_aU94Erv48.033mGxguN1UHKLizWmVpZ5Q9tHHCvr6OHtXmYZJY7MGN4UYbRB.Rpzav3AsHGKtGU0nGmJhqA7djF7JqugwvCYM9bDnjlNfJFQWonIC.cVjdSpavFnHZi_6IyWAO817f7Ie48EAOqhkg"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=91350805fcacf8ca';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, "\/abstracts\/search?q=indefinite%20blocking&__cf_chl_rt_tk=ggEuiL.kg0VYjbXziwZ_a1tUi3K6Y5pIm4xOYE8al4A-1739787485-1.0.1.1-QrerzShjgzZUDKbUz4mujPAT8AxeWfVaiiWqVaq9zvc" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>