DC 欄位 值 語言 DC.contributor 太空科學研究所 zh_TW DC.creator 徐浩翔 zh_TW DC.creator Haung-Xiung Xu en_US dc.date.accessioned 2001-6-19T07:39:07Z dc.date.available 2001-6-19T07:39:07Z dc.date.issued 2001 dc.identifier.uri http://ir.lib.ncu.edu.tw:88/thesis/view_etd.asp?URN=88623002 dc.contributor.department 太空科學研究所 zh_TW DC.description 國立中央大學 zh_TW DC.description National Central University en_US dc.description.abstract 本論文分析1996太陽黑子極小年中壢中央大學校園內（24.91°N, 121.24°E geographic）數位電離層探測儀（Digisonde Portable Sounder； 簡稱DPS）所觀測記錄三萬多張之電離圖以研究位於台灣地區赤道異常區之上空電離層中之散塊E層（Sporadic E layer, Es層）變化，除電腦自動判圖外，並輔以人工判圖以增加資料之可信度。統計最大反射頻率foEs，反射虛高h’Es以及Es層出現機率之整年變化情形。結果顯示台灣地區foEs以3~4MHz為主，而於夏季有明顯較高的趨勢。h’Es主要分布在100至105km之間，冬季h’Es之變化幅度較夏季為明顯。一天24小時Es層出現機率與h’Es於不同的月份而有單峰及雙峰的現象。Es層變化與太陽的活動性並無明顯相關，但於強烈的磁擾動時其出現機率有減少之趨勢。仿照異調散射雷達ISR電子密度隨高度及時間變化圖之表現方式處理DPS 之觀測資料以探討Es層變化與中界層現象之相關性。 zh_TW dc.description.abstract The sporadic E (Es) layer is an irregular layer occurred in the ionosphere. Unlike the normal E layer critical frequency (foE), the foEs and h’Es are highly variable in time and space. To understand the occurrences of the Es layer in the equatorial anomaly region, more than 30,000 ionograms recorded by a digisonde portable sounder, DPS, at National Central University, NCU, (24.91°N, 121.24°E) during 1996 (solar minimum) have been examined. The intermediate and descending layers in the valley between E and F regions can also be observed by NCU DPS. In this study, variations of the Es layer at various local times, seasons, solar radiations, geomagnetic conditions and the observation of intermediate and descending layers are presented and discussed. en_US DC.subject 中界層 zh_TW DC.subject 散塊E層 zh_TW DC.subject intermediate layer en_US DC.subject sporadic E en_US DC.title 台灣地區1996年散塊E層之變化 zh_TW dc.language.iso zh-TW zh-TW DC.type 博碩士論文 zh_TW DC.type thesis en_US DC.publisher National Central University en_US