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非線性微分方程式 t^2u"=u^p / On the nonlinear differential equation t^2u"=u^p姚信宇 Unknown Date (has links)
回顧一個重要的非線性二階方程式
d/dt(t^p(du/dt))+(-)t^(sigma)u^n=0,
這個方程式有許多有趣的物理應用,以Emden方程式的形式發生在天體物理學中;也以Fermi-Thomas方程式的形式出現在原子物理內。對於此類型的非線性方程式可以用來更頻繁且深入的探討數學物理,雖然目前仍存在著些許不確定性,不過如果在未來能有更全面的了解,這將有助於用來決定物理解的性質。
在這篇論文當中,我們討論微分方程式
t^2u"=u^p,p屬於N-{1},
其正解的性質。這個方程式是著名的 Emden-Fowler 方程式的一種特殊情形, 我們可以得到其解的一些有趣的現象及結果。 / Recall the important nonlinear second-order equation
d/dt(t^p(du/dt))+(-)t^(sigma)u^n=0,
this equation has several interesting physical applications, occurring in astrophysics in the form of the Emden equation and in atomic physics in the form of the Fermi-Thomas equation. These seems a little doubt that nonlinear equations of this type would enter with greater frequency into mathematical physics, were it more widely known with what ease the properties of the physical solutions can be determined.
In this paper we discuss the property of positive solution of the ordinary differential equation
t^2u"=u^p, p belongs to N-{1},
this equation is a special case of the well-known Emden-Fowler equation, we obtain some interesting phenomena and resulits for solutions.
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廣義估計方程式在題組式測驗的應用 / Generalized estimation equation in Testlet-based educational testing李介中, Lee, Chieh Chung Unknown Date (has links)
在測驗含有題組(testlet)結構時,由於違反了試題反應理論(Item Response Theory, IRT)中局部獨立性的假設,使得IRT的估計方法產生偏誤,過去研究的解決方式為在IRT模型中多加入一個參數,將題組的影響力納入模型中,此即為題組反應理論(Testlet Response Theory, TRT),在貝氏(Bayesian)的架構下,此方法的計算則可透過SCORIGHT軟體來達成。本研究旨在透過另一種方法,即廣義方程式(Generalized Estimation Equation, GEE)去處理測驗中的題組效果。GEE過去常被使用於分析縱貫式(longitudinal)的資料,本研究使用此方法來捕捉題組測驗下作答結果的相關性,並經重新參數化調整係數後使其能對受試者能力值進行估計。
電腦模擬的結果顯示GEE能有效的處理題組效果帶來的影響。在GEE和貝氏題組模型的比較上,GEE對於程度好和程度差的受試者有較佳的估計效果;而貝氏題組模型則對於程度中等的受試者表現較好,此外我們也針對GEE的估計效率進行了實驗,結果顯示先將受試者依能力分組再進行GEE估計能提升GEE的估計效率。
在文章中,我們也展示了使用GEE計算題組訊息量的方式,做為題組式測驗下評估該測驗對於各能力區間的受試者在估計準確度上的參考。 / If the tests have testlet structure, the bias may arise when using traditional Item Response Theory(IRT) estimation methods due to the violations to the assumption of local independence. To deal with the testlet effect, previous studies introduced a new parameter to the classical IRT model which called Testlet Response Theory(TRT). Under the Bayesian framework, the estimation can be accomplished on the SCORIGHT program. The purpose of this paper is to use another method named Generalized Estimation Equation(GEE) to model testlet response data. GEE was commonly used to analyze the longitudinal data. We use this method to capture the information from the correlated items and estimated ability of the examinees through re-parametrization.
Simulation results indicate that GEE can deal with the testlet effect effectively. On the comparison between GEE and Bayesian testlet model, GEE does better on estimation of the examinees who have high or low ability level. In contrast, Bayesian testlet model does better on estimation of medium ability level. In addition, we design the experiment to test the efficiency of GEE. The results show that group the examinees according to their ability before doing the GEE estimation can improve the efficiency of GEE.
In this paper, we also demonstrate the method to calculate testlet information using GEE which can be taken as reference for assessing estimation accuracy of each ability level in testlet-based testing.
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情報決策象限理論之建構與個案分析-孫子兵法情報概念的反思 / The Construction and Case Study of the Quadrangular Theory for Intelligence-Decision:Reflection on the Intelligence Thought of Sun Tzu.紀光陽, Chi,Kuang Yang Unknown Date (has links)
「情報」與「決策」存在著高度的密切關係,「情報」正確而及時則相對提高「決策」的正確性;反之,則降低「決策」的正確性。但同一個「情報」對不同的個人而言,會產出不同的「決策」結果,此即是「決策」不僅與「情報」有關,亦與個人的「認知」條件有著密切的關係。
因此,本文透過孫子兵法「情報」與「決策」的關係,架構出孫子的決策邏輯與位階性,再以此建構出情報決策「象限理論」,企圖系統性地解釋「情報」條件與決策者「認知」條件的複雜關係,並藉由第二次美伊戰爭的決策過程作為例證,說明導致決策錯誤的重要因素。並由「象限理論」中第一象限區域,及美伊戰爭決策缺失中,檢討並演繹出「國家安全決策新思維」,文中指出一個專業且中立的情報機關,除了要提升情報信息的客觀性外,更要避免、改變決策者先入為主的錯誤認知。經由本文所提出的「象限理論」、「決策方程式」、「個案分析」、「國家安全決策新思維」,將有助於瞭解並加速決策產出的質量與效能,進而有利於優質決策的產出。 / There is highly relationship between intelligence and decision-making. The correct and on time intelligence will make a good policy; but the wrong or slow intelligence will make a bad policy, on the contrary. The same intelligence for different individuals will result in different decision-making, which means decision-making has high relationship with intelligence and personal cognition.
For this reason, this article constructs The Quadrangular Theory of Intelligence and Decision-making based on The Art of Sun-tzu theory, to explain the complicated relation between intelligence and personal cognition, as well as to state the important factor which leads to the wrong decision-making in the Second Gulf War.
This article also point out an important concept: the professional and intelligence agencies will not only improve the objectively intelligence, but also will avoid policymaker's prejudiced cognition. The Quadrangular Theory of Intelligence and Decision-making will help to understand the whole situation and accelerate the high quality and high efficiency decision-making process.
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潛在移轉分析法與中位數法在長期追蹤資料分組的差異比較 / On classification of longitudinal data ─ comparison between Latent Transition Analysis and the method using Median as a cutpoint李坤瑋, Lee, Kun Wei Unknown Date (has links)
當資料屬於類別型的長期追蹤資料(Longitudinal categorical data)時,除了可以透過廣義估計方程式(General estimate equation, GEE)來求解模型參數估計值外,潛在移轉分析(Latent transition analysis, LTA)法也是一種可行的資料分析方法。若資料的期數不多,也可以選擇將資料適度分群後使用羅吉斯迴歸分析(Logistic regression)法。當探討的反應變數為二元(Binary)型態,且觀察對象於每一期提供多個測量變數值的情況之下,廣義估計方程式與羅吉斯迴歸分析法的使用,文獻上常見先將所有的測量變數值加總後,以「中位數」作為分類的切割點。不同於以上兩種方法,潛在移轉分析法則是直接使用原始資料來取得觀察對象的潛在狀態相關訊息,因此與前二者的作法不同,可能導致後續的各項分析結果有所差異存在。
為了能夠了解造成中位數分類法與移轉分析法差異的可能因素,我們架構在潛在移轉分析法的模型下,以不同的參數設定來進行電腦模擬,比較各參數條件下的兩分類方法差異。結果發現各潛在狀態下的測量變數反應機率形式、第一期潛在狀態的組成比例等皆會對兩分類方法是否具有相同分類有所影響。另外,透過分析「青少年媒體使用與健康生活調查」的實際資料得知,潛在移轉分析會將大部分的觀察對象歸屬於「網路成癮」,而中位數分類法則是將大部分的觀察對象歸屬於「無網路成癮」。此外,可以注意到「沮喪」、「線上情色每星期平均使用天數」、及「父母相處狀況」這幾個控制變數與各分組結果的關聯性,於上述三種資料分析方法中有所不同。 / Several methods can be used to analyze longitudinal categorical data, as among them Latent Transition Analysis (LTA), and Generalized Linear Models estimated by Generalized Estimating Equations (GEE) probably the most popular. In addition, if the number of periods is two, then with certain grouping of data, the Logistic Regression can also be applied to perform the analyses.
When there are more than one manifest response variable for each study subject, LTA is able to classify the subjects in terms of the original manifest response variables and proceeds with necessary analyses. On the other hand, GEE method and Logistic Regression lack the flexibility, and require certain transformation to transform the manifest response variables into a categorical response variable first. One common way to form a binary response is to sum all manifest variables, and then taking median as a cut-point.
In this study, we explore the differences of the classification resulted from LTA directly and using median as a cut-point through simulations. An empirical study is also provided to illustrate the classification differences, and the differences on the subsequent analyses using LTA, GEE method, and Logistic Regression approach.
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含遺失值之列聯表最大概似估計量及模式的探討 / Maximum Likelihood Estimation in Contingency Tables with Missing Data黃珮菁, Huang, Pei-Ching Unknown Date (has links)
在處理具遺失值之類別資料時,傳統的方法是將資料捨棄,但是這通常不是明智之舉,這些遺失某些分類訊息的資料通常還是可以提供其它重要的訊息,尤其當這類型資料的個數佔大多數時,將其捨棄可能使得估計的變異數增加,甚至影響最後的決策。如何將這些遺失某些訊息的資料納入考慮,作出完整的分析是最近幾十年間頗為重要的課題。本文主要整理了五種分析這類型資料的方法,分別為單樣本方法、多樣本方法、概似方程式因式分解法、EM演算法,以上四種方法可使用在資料遺失呈隨機分佈的條件成立下來進行分析。第五種則為樣本遺失不呈隨機分佈之分析方法。 / Traditionally, the simple way to deal with observations for which some of the variables are missing so that they cannot cross-classified into a contingency table simply excludes them from any analysis. However, it is generally agreed that such a practice would usually affect both the accuracy and the precision of the results. The purpose of the study is to bring together some of the sound alternatives available in the literature, and provide a comprehensive review. Four methods for handling data missing at random are discussed, they are single-sample method, multiple-sample method, factorization of the likelihood method, and EM algorithm. In addition, one way of handling data missing not at random is also reviewed.
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動態遞迴式神經網路之研究 / Research on Dynamic Recurrent Neural Network林明璋, Lin, Ming Jang Unknown Date (has links)
此篇論文,主要是討論遞迴式神經網路。在文中,我們將架構一個單層的神經網路結構。並利用三種不同的學習法則來套用此架構。我們也做了圓軌跡和圖形8的模擬,以及討論了此架構的收斂性。 / Our task in this paper is to discuss the Recurrent Neural Network. We construct a singal layer neural network and apply three different learning rules to simulate circular trajectory and figure eight. Also, we present the proof of convergence.
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從科技接受整合模型探討民眾對電子化政府入口網的使用意圖 / To explore people’s intentions to use e-government portal from integrated technology acceptance models林衍儒 Unknown Date (has links)
本研究以科技接受模型為基礎,企圖整合資訊品質、系統品質和網站服務品質作為認知有用性和認知易用性的前置變項,期待了解三種品質構面對科技接受模型的影響效果,藉以探討民眾在使用電子化政府入口網時,會受到何種網站品質的影響,增加其使用意圖,以獲得對電子化治理的相關理解。另外本研究並嘗試以形成性指標的方式建構三種品質構面,以修正過去文獻誤用品質構面為反映性指標的情形。
透過線上問卷系統*蒐集1459位民眾的意見後,本文的研究結果顯示對認知易用性影響最大者為網站服務品質,認知有用性則受到認知易用性最大影響。對使用意圖有最大影響者為使用者的態度。三種品質的形成性指標對品質構面皆可達到顯著,在解釋上較為符合品質構面應為形成性指標的建構形式。文後並提供了對政府建置政府網站的實務建議,希冀能夠對未來政府網站建置提供參考。 / Based on technology acceptance model(TAM), this study develops a reaserach model that integrate information quality, system quality and website service quality as antecedents of perceived usefulness and perceived ease of use. The purpose of study is to explore how the three quality might influence technology acceptance model, and what might strengthen user intention on e-government portal website. In addition, this study develops quality constructs as “formative-indicators”rather than reflective ones to correct the misuse of some literatures.
The model is then tested using a sample of 1459 users from online survey and analyzed the data using structural equation modeling. The results show that(1) website service quality(WSQ) have the most effects on ease of use(EOU), and that (2)ease of use have the most effects on usefulness(PU). They also demonstrate that (3)attitude predit user intention the most. The significance illustrate logically the relation between formative-indicators of three quality and the constructs. Implications of this study for research and practice are presented.
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複雜適應系統之經營模式建構與比較 / Complex adaptive systems business models construction and comparison黃理箴, Huang, Lea Jen Unknown Date (has links)
邁入21世紀,許多環境趨勢與變動如全球化浪潮、時基競爭、快速回應的壓力等,使現代組織面臨另一波的典範轉移。面對如此動盪的環境,近年來一些組織為了得以快速地感知與因應環境變動,開始由單一組織的營運活動逐漸轉變為「跨組織」、甚至「跨產業」的連結與互動,透過組織間價值利益交換與共同演化,產生高度的適應性與多樣性,得以與複雜不確定的動盪環境共存。組織間連結關係的普遍,使得學術界與實務界開始將關於企業競爭力的探討,由組織內在能力之強調轉移至與組織生存攸關之外部資源的管理上。而對於企業來說,發展的關鍵就是如何與其他企業相互協調、將資源集中起來為消費者創造價值。
本研究從複雜適應系統(Complex Adaptive Systems)角度出發,試圖剖析一「組織間連結」群體之現有樣貌與未來可能樣貌。本研究首先針對相關文獻、研究進行整理,由系統觀點找出複雜適應系統的組織發展光譜,並提出其中商業生態系統(Business Ecosystem)與混序式組織(Chaordic Organization)兩個組織類型將座落於此組織發展光譜之兩端,而混序式組織將可視為一複雜適應系統的最終理想境界,如同相關文獻所述。
本研究更進一步針對兩種組織類型內涵進行解構,並佐以現行個案:台積電公司與Visa國際組織進行實例驗證,歸納出「生態型」與「混序型」兩種經營模式,並於共同特徵與對稱差異分析下,得出以下結論與管理意涵: 1)未來動盪環境之下,組織協議力量(protocal)將取代傳統控制力量,促成網絡內部之複雜與多樣性;2) 協議力量下,未來組織之創新將發生在價值活動的任何一端,屬「激發創新」;3) 面對動盪環境,組織複雜與適應性的建立,將會是不斷重複且持續循環的任務與挑戰。
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発展系の数値解析の総合的研究三井, 斌友, 小川, 知之, 小澤, 一文, 大野, 博, 小野, 令美, 久保田, 光一, 小藤, 俊幸, 齊藤, 善弘, 篠原, 能材, 鈴木, 千里, 中尾, 充宏, 中島, 正治, 前田, 茂, 室田, 一雄, 吉田, 春夫 03 1900 (has links)
科学研究費補助金 研究種目:基盤研究(A)(1) 課題番号: 研究代表者:三井 斌友 研究期間:1996-1998年度
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大気中メタンの発生源評価-大気拡散モデル解析・大気放射能測定・同位体比測定によって-飯田, 孝夫, 池辺, 幸正, 吉田, 尚弘, 中村, 俊夫 03 1900 (has links)
科学研究費補助金 研究種目:基盤研究(B)(2) 課題番号:08458144 研究代表者:飯田 孝夫 研究期間:1996-1997年度
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