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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

非線性時間數列模糊轉捩區間之確認 / Fuzzy change period identification for the nonlinear time series

李玉如, Lee, Alice Unknown Date (has links)
對於一個具有結構性改變性質的非線性時間數列,通常很難判斷何處為轉 捩點,或者何處為所謂的轉型期。雖然長久以來已有不少偵查轉捩點的方 法被提出,但是對於轉捩區間以及對於一些語言性的時間數列資料問題( 例如:景氣指標的紅綠燈時間數列),都很少被提出來。本論文中,我們 首先引用Zadeh於1965年提出來的模糊理論的觀念來介紹糢糊時間數列( FTS)。進而定義出在□水準下的模糊點(FP)和模糊轉捩區間(FCP), 並且證明了一些有用的性質。最後再以台灣地區出生率資料為例,說明□ 水準的模糊轉捩區間的判定方法,並列出了詳細的執行步驟。實驗結果更 證明出我們的模糊檢驗法非常具有實用性及有效性。 / As far as structural change of a non-linear time series is concerned, it is hard to tell when the change point or the fuzzy change period occurs. Though many methods are used for the task of detecting, most of them primarily deal with the case of change point, and few examine the problem of fuzzy change period and linguistic time series ( for example, the index of prosperity represented by red or green light ). In this article, we adopt the theory of fuzzy which is proposed by Zedeh ( 1965 ) to introduce the concept of fuzzy time series ( FTS ). Furthermore, we define the □level of fuzzy point (FP) as well as fuzzy change period (FCP), and prove some useful properties. Finally we explain the method we proposed in detecting the □level of fuzzy change period in terms of the data of Taiwan birth rate and provide step-by-step procedures. Experimental results show that the proposed method of fuzzy detecting is available and practical in detecting the □level of fuzzy change period.
22

媒介記憶與新聞儀式-二二八事件新聞的文本分析(1947-2000)

夏春祥 Unknown Date (has links)
本研究主要探討新聞媒介如何建構過去,二二八事件則為研究案例。所關心的問題有二二八事件在新聞上的集體記憶有哪些?如何分類?它們的變遷情形又如何?研究中所採取的方法,則為文本分析法。 在二二八的媒介記憶中,共計可分為三個階段十七種類型。第一階段為1947年的事件初始期,有合理改革等五種類型、第二階段則為1948年到1983年的社會失憶期,包括了偶發型、共黨叛國型與遺忘型等三種類型。第三階段的眾聲喧嘩期,由1984到2000年,共計有派系鬥爭型等九種類型。十七種類型的分類依據,是依照新聞論述所形成的文化景觀而來,它們先後出現在1947年至今的台灣社會之中,並累積形成四種傷痛記憶的理念型要素,分別是污名、壓抑、故事/戲劇,以及形式化等。 在研究中,我們發現二二八新聞在事件初始、社會失憶期,以及眾聲喧嘩期等三階段的分佈數量有很大的落差。社會失憶期的新聞只有區區數則,這構成了台灣社會中的結構性健忘。而新聞在二二八事件的發展過程中也有了相應的變與不變。不變的部分,如新聞的本質是論述的,故新聞論述實比新聞報導為更適合的描述詞彙。變化者則有大眾傳媒在台灣社會中的角色變遷,從最早的「宣傳者」、到後來的「國家意識型態機器」等,其執行的功能也有凝聚個體於社會、抒解集體情緒,以及文化實踐等不同作用。本文主張以「詮釋社群」的概念來理解新聞事業,以補傳統上「侍從報業」之不足,這是新聞儀式觀點的具體表現。
23

從日本NTT DoCoMo公司探討雙面式組織之運作 / From NTT DoCoMo to Analyze The Operation of Ambidextrous Organization

趙基楠, Chao,Chi-Nan Unknown Date (has links)
組織在持續發展的進程中會逐漸的由有機型轉而為機械型組織的狀態,然而隨著外在環境趨向超競爭的型態,使其核心技術將有過時之虞,所以組織必須成立新部門以隨時觀察並利用外在之機會,因此組織內新舊部門並列的現象成為企業運作實務的常態。不過新舊部門之間並非必然只能夠各自獨立運作,其間能夠透過持續倡導「可容納新舊部門」的願景下,讓新舊部門透過組織高層主持的跨部委員會之居中協調達到提升彼此績效之正向螺旋效果,如此之組織形式在文獻上稱為「雙面式組織」。 本研究之進行首先由內而外探討雙面式組織定義與內在核心構成要素:其核心概念分為由高層主導之結構性雙面式思維,其用意在於由高層設立跨部會機制以影響成員行為,而系絡性雙面式思維在於由基層員工主動引導跨部會行動,進而影響高層做出相對應之措施,而以上概念對應外在的組織構成形式則可分為結構性、系絡性與混合結構與系絡性之雙面式組織三種;而其間之知識管理模式主要概念在於「先讓成員從共同擬定價值觀,之後再使成員自發性的針對議題進分享彼此知識並進一步及於知識的整合與創造」。 接續以NTT DoCoMo研發i-mode系統為例,說明雙面式組織在企業實務運作之「從封閉平台之電信加值思維到開放平台之網路創值思維」的策略重思考、「透過具跨部門性質之策略性社群與凝聚各策略性社群共識之領導性策略事業群」的組織轉型與「主持策略性社群內 / 間互動與雙面式組織內部之知識發掘、擴散與累積」之變革管理的議題,並透過對個案評論與不同個案之輔助以期使雙面式組織之具體運作使說明更為全面。 在個案描述與評論之後,本研究針對雙面式組織的運行提出以下的三個推論:第一,組織高層應在可容納新舊部門思維之共同目標前提下,確立新舊部門之間的分工與合作機制,以免新舊部門因為彼此爭利而落得兩敗俱傷的局面;第二,在雙面式組織的有效運作中,各社群領導人富有包容力的領導方式與具備前瞻性的領導眼光是其成功的關鍵;第三,組織結構式雙面性與系絡式雙面性思維之運作過程是一體兩面且環環相扣,而且當雙面式組織的運作模式被長期使用時,組織內部的運作會同時包含以上所提及之兩種思維。 / As time goes by, organizational structure will be transformed from organic to mechanic form. However, organization must start a new division because the condition of hyper-competition would make core technology become obsolete. Therefore it is so common that new and old divisions co-exist in an organization, but they are not necessarily operated independently. Between them can both attain higher positive-spiral performance through the cross-division committee under “compatible of new and old divisions” vision and such the organizational structure is called “Ambidextrous Organization” in literatures. In this research, ambidextrous organization will be discussed from inner sides to outer ones: starting from the definition and core composing thoughts: structural ambidexterity, which means training employees’ behaviors to be ambidextrous through structural changes, and contextual ambidexterity, which means upper managers’ ambidextrous actions are stimulated from middle or lower employees. Following the core composing parts matches not only the external structural forms: structural ambidextrous organization, contextual ambidextrous organization, and organization which mix the thoughts of structural and contextual ambidexterity but also the process from value resonance of co-workers to knowledge sharing and creation. Following the case analyzing method will be used to explain the operation of ambidextrous organization putting into practice: Take NTT DoCoMo for instance, this research will show the strategic rethinking of” from close platform of telecom value-added concept to open platform of internet value-creation concept”, the corporate transformation of” cross-divisional strategic community and leadership-based strategic community which converge a common consensus of all strategic communities” and the change management of” directing the interaction among strategic communities and knowledge discovering, distributing, and accumulating”. Case comment and other supportive cases will be mentioned to fully analyze the concrete operation of ambidextrous organization. After the case description and comment, this research will further propose three propositions: First, high level managers should take visions comparable of new and old divisions or they would be in serious wrangling over the resources. Second, considerate and visionary leading competence is the key to successfully managing the operation of ambidextrous organization. Third, structural and contextual ambidexterity thoughts are interactive and mutual-inclusive, especially when using the system of ambidextrous organization for a long time.
24

有關對調適與演化機制的再審思-在財務時間序列資料中應用的統計分析 / Rethinking the Appeal of Adaptation and Evolution: Statistical Analysis of Empirical Study in the Financial Time Series

林維垣 Unknown Date (has links)
本研究的主要目的是希望喚起國內、外學者對演化科學在經濟學上的重視,結合電腦、生物科技、心理學與數學於經濟學中,希望對傳統經濟學上因簡化假設而無法克服的實際經濟問題,可以利用電腦模擬技術獲得解決,並獲取新知與技能。 本研究共有六章,第一章為緒論,敘述緣由與研究動機。第二章介紹傳統經濟學的缺失,再以資料掘取知識及智慧系統建構金融市場。第三章則介紹各種不同人工智慧的方法以模擬金融市場的投資策略。第四章建立無結構性變遷時間序列模型--交易策略電腦模擬分析,僅以遺傳演算法模擬金融市場的投資策略,分別由投資組合、交易成本、調適性、演化、與統計的觀點對策略作績效評分析。第五章則建立簡單的結構性變遷模型,分別由調適性與統計的觀點,採取遺傳演算法再對投資策略進行有效性評估分析。第六章則利用資料掘取知識與智慧系統結合計量經濟學的方法,建構遺傳演算法發展投資策略的步驟,以台灣股票市場的資料進行實証研究,分別就投資策略、交易成本、調適性與演化的觀點作分析。最後一章則為結論。 未來研究的方向有: 1. 其他各種不同人工智慧的方法的比較分析,如人工神經網路、遺傳規劃法等進行績效的交叉比較分析。 2. 利用分類系統(Classifier System)與模糊邏輯的方法,改善標準遺傳演算法對策略編碼的效率,並建構各種不同的複雜策略以符合真實世界的決策過程。 3. 建構其他人工時間資料的模擬比較分析,例如ARCH (Autoregressive Conditional Heteroskedasticity)模型、Threshold 模型、 確定性(Deterministic) 模型等其他時間序列模型與更複雜的結構性變遷模型。 4. 進一步研究遺傳演算法所使用的完整資訊(例如,各種不同指標的選取)。 5. 本研究係採用非即時分析系統(Offline System),進一步研究即時分析系統 (Online Sysetem)在實務上是有必要的。 / Historically, the study of economics has been advanced by a combination of empirical observation and theoretic development. The analysis of mathematical equilibrium in theoretical economic models has been the predominant mode of progress in recent decades. Such models provide powerful insights into economic processes, but usually make restrictive assumptions and appear to be over simplifications of complex economic system. However, the advent of cheap computing power and new intelligent technologies makes it possible to delve further into some of the complexities inherent in the real economy. It is now feasible to create a rudimentary form of “artificial economic life”. First, we build the framework of artificial stock markets by using data mining and intelligent system. Second, in order to analyze competition among buyers and sellers in the artificial market, we introduce various methods of artificial intelligence to design trading rules, and investigate how machine-learning techniques might be applied to search the optimal investment strategy. Third, we create a miniature economic laboratory to build the artificial stock market by genetic algorithms to analyze investment strategies, by using real and artificial data, which consider both structural change and nonstructural change cases. Finally, we use statistical analysis to examine the performance of the portfolio strategies generated by genetic algorithms.

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