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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.
91

內生成長與通膨率目標政策: 封閉經濟的分析 / Endogenous growth and inflation rate targeting policy in a closed economy

邱奕棟 Unknown Date (has links)
本文引用Zhang(1996)和Suen and Yip(2005)提出的貨幣具有降低交易成本的特性,建構封閉經濟體的貨幣內生成長模型,分別探討在投資有或沒有調整成本的情況下,政府採取釘住通貨膨脹目標政策對於經濟成長的影響,以及經濟體系的安定性。 本文的結論可以歸納為:(1)當投資不具有調整成本時,政府調高目標通膨率會使得經濟成長率下降,且經濟體系呈現確定性;(2)當投資調整成本時,政府調高目標通膨率也會使得經濟成長率下降,但經濟體系卻呈現不確定性。 / This thesis sets up a monetary endogenous growth model for a closed economy, in which monetary authorities implement a monetary policy of inflation rate targeting. The main feature of the model is that, in line with Zhang (1996) and Suen and Yip (2005), money plays a role to facilitate transactions of output, and hence holding money can lower the transaction cost. This thesis then uses the model to investigate whether the economy’s growth rate and the dynamic stability are closely related to the implementation of inflation rate targeting. Two main findings emerge from the analysis. First, when investment does not involve adjustment costs, a rise in the inflation rate lowers the balanced economic growth rate and the equilibrium is characterized by local determinacy. Second, when investment involves adjustment costs, a rise in the inflation rate lowers the economic growth rate and the equilibrium is featured with local indeterminacy.
92

高精度傾斜計測による大規模地下空洞の安定性監視に関する研究

廣岡, 知 23 July 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21307号 / 工博第4505号 / 新制||工||1701(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 小池 克明, 教授 石田 毅, 准教授 塚田 和彦 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
93

Water, Heat and Solute processes in Seasonally frozen Soils : Experimental and Modeling Study

Wu, Mousong January 2015 (has links)
Soil freezing and thawing is of importance in transport of water, heat and solute, which has coupled effects. Solute type and solute content in frozen soil could influence the osmotic potential of frozen soil and decrease freezing point, resulting in differences in soil freezing characteristic curves under various solute conditions. Prediction model provides an approach for estimating soil freezing characteristic curves under various water and solute conditions based on soil freezing characteristic curve obtained at certain water and solute conditions. Water, heat and solute transport in seasonally frozen soil is a coupled process strongly linked to evaporation and energy balance of soil surface. High solute content and shallow GWTD provide good conditions for water and solute accumulation in surface layer, which would result in more evaporation during thawing. Also, high solute content in upper layer would cause more liquid water to exist in upper layer, which may enhance evaporation during freezing period. Obvious increase in cumulative evaporation amount was detected for frost tube experiments, 51.0, 96.6, to 114.0 mm when initial solute content increased from 0.2%, 0.4%, to 0.6%, and initial GWTD of 1.5 m. Similar trends were observed for other GWTD and solute treatments. Water and heat transport simulated by the CoupModel combined with GLUE calibration showed good performances, when constrained by certain criteria. Uncertainties were investigated using ensemble of modeling results. Simulated energy partitioning showed intensive oscillations in daily courses during soil freezing/thawing periods and strongly influenced the stability of energy system on surface of soil. The study demonstrated the complexity in water, heat and solute transport in seasonally frozen soil, and the necessity of combining experimental data with numerical model for better understanding the processes as well in decision making for irrigation district water resources management. / 土壤冻融过程对于水热及溶质的运移具有十分重要的影响,并对于寒旱区水文过程的研究有着深远意义。在冻土中,溶质的种类及溶质含量会对土壤溶质势产生影响,并导致冰点的降低,进而影响土壤冻结曲线的变化。本研究通过建立含盐冻土冻结曲线的预报模型,有效地利用一定水盐试验条件下的冻结曲线对未知条件下的冻结曲线进行预测,进而为数值模型实时根据土壤水盐条件获得准确的液态含水量与温度的关系时提供了可行的方法。冻融土壤中的水热盐运移过程与地表的水热平衡有着密切联系,进而影响冻融土壤蒸发过程。试验研究表明,高溶质含量及浅埋深地下水条件为地表的蒸发提供了便利条件,因为高溶质含量土壤冰点降低,同一负温条件下的液态含水量增大,为蒸发提供了可利用水分;而浅埋深地下水对冻融期水盐的表聚提供的方便,进而有助于融化期地表水分的大量蒸发及下层土层水分的大量向上补给。例如,当地下水初始埋深设置在1.5 m时,对于初始含盐量分别为0.2%,0.4% 和0.6% g/g的冻融试验组,冻融期累积蒸发量分别为51.0,96.6和114.0 mm。同样的增加趋势在其它初始地下水埋深设置试验组里也被验证,且初始地下水埋深越浅,累积蒸发量也越大。CoupModel 与GLUE相结合的方法能够有效地根据实测数据对模型进行率定并经过筛选后得出较好的模拟结果集合。通过对筛选的模拟输出集合的不确定性分析,对模型模拟过程的不确定性有了很好的了解。模拟的地表能量分配过程显示,地表能量的日变化过程较为剧烈,并且对地表能量平衡系统的稳定性产生了显著影响。研究通过试验与模拟相结合的方法,展示了季节性冻融土壤中水热盐耦合运移过程的复杂性,同时也表明利用试验取样与数值模型相结合的方法研究冻融土壤中水热盐运移过程的必要性,并为高效的水资源管理决策的制定提供了有效的手段。 / <p>QC 20150518</p>
94

降雨時列車運転規制への活用のための地形性降雨を考慮した短時間降雨予測手法の開発に関する研究

中渕, 遥平 25 September 2023 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第24893号 / 工博第5173号 / 新制||工||1988(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 中北 英一, 教授 佐山 敬洋, 教授 田中 賢治 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
95

以變異數比率法檢定指數選擇權之買賣權平價理論——馬可夫狀態轉換模型之應用

秦秀琪 Unknown Date (has links)
本研究目的在於探討Put-Call Parity(PCP)所隱含的買權、賣權與標的資產間的價格變動關係。藉由探討PCP偏差程度的動態行為,推論若PCP的偏差為隨機漫步過程,則無法達到長期穩定,隱含PCP的廣義關係無法成立;反之,若PCP的偏差具有回歸平均特性,表示長期會達到穩定狀態,則PCP的廣義關係成立。 在研究方法上本文以變異數比率法檢定指數選擇權的PCP偏差是否為隨機漫步過程,採用隱含利率和實際無風險利率的差代表PCP的偏差程度,利用馬可夫轉換模型描繪PCP偏差的動態行為,並使用Gibbs Sampling演算法說明參數的不確定性。 本文以S&P500和DAX為研究標的,並探討股利不確定性是否影響PCP廣義關係,得到下列結論: 1、 對於S&P 500指數選擇權而言,不論是以日資料或週資料估計VR,S&P 500的PCP偏差都無法提供回歸平均的證據,隱含S&P 500的PCP廣義關係無法成立。 2、 對於DAX指數選擇權而言,檢定日資料的結果發現,DAX之PCP偏差在長期時(40~50日)有明顯的回歸平均的證據;而在檢定週資料時,使用原始資料法在90%信心水準下,不論取任何lag都可拒絕虛無假設,使用標準化資料則無法提供明顯的回歸平均證據。 3、 比較S&P 500和DAX,檢定日資料與週資料的結果都發現,DAX的p-value都比S&P 500小,並且S&P 500的PCP偏差都無法提供回歸平均的證據,而DAX有明顯回歸平均現象,隱含在消除股利的不確定性後,指數選擇權PCP的廣義關係式成立之證據較強烈。
96

公共工程技術服務契約爭議問題之研究

李仁豪 Unknown Date (has links)
本文旨在探討及釐清公共工程技術服務契約之民事爭議問題,包括定型化契約條款效力之爭議、契約定性及適用法律之爭議、廠商服務缺失責任之爭議、廠商服務酬金請求權之爭議等。 首先,依據民法第二四七條之一規定,判斷公共工程定型化技術服務契約條款是否對廠商顯失公平而無效時,本文認為,應就個案為全盤考量及實質審查,以誠信原則及公平互惠為上位概念,併參考消保法規定,俾達保護弱勢契約一方、對抗強勢契約他方、節省締約成本及實現契約正義之目的。 其次,經本文分析、歸類及定性,實務上存在十種一般性之公共工程技術服務契約類型,其中,提供「辦理規劃」、「辦理設計」者,為承攬契約;提供「協辦工程招標及決標」、「辦理監造」者,為委任契約;同時包含前項及後項者,為承攬及委任之混合契約,其適用法律之道為,前項與「協辦工程招標及決標」混合者,整體適用關於承攬契約之法律規定;各項與「辦理監造」混合者,則分別適用各該部分給付所屬契約類型之法律規定。 再者,關於廠商服務缺失責任,本文探討規劃或設計廠商瑕疵擔保責任之「工作物完成前之瑕疵擔保責任」、「瑕疵發見期間」、「修補瑕疵」、「解除契約」,監造廠商受任人損害賠償責任之「善良管理人注意義務」、「受任人逾越權限行為之損害賠償責任」,以及債務不履行與侵權行為責任之「瑕疵擔保責任及不完全給付責任之競合」、「契約責任及侵權責任之競合」、「第三人與契約責任之關係」、「僱用人與侵權責任之關係」、「侵權行為舉證責任之緩和及減輕」等具體爭議。 最後,關於廠商服務酬金請求權,本文探討規劃或設計廠商依約完成工作之「瑕疵擔保義務與承攬報酬義務之同時履行抗辯」、「工作是否完成與對價平衡之關係」、「採委任契約之可能性」,規劃或設計廠商辦理變更設計之「實務見解」、「屬規劃或設計瑕疵所致之變更設計」、「屬機關需求變更所致之變更設計」、「屬非可歸責於雙方情事所致之變更設計」,以及監造廠商工期展延之「情事變更原則」、「棄權條款之適法性」等具體爭議。
97

穩定性與多重性-以二部門體系動態調整方式為例 / Stability and indeterminacy --the dynamic adjustment of two-sector economy

連科雄, Lian, Ke-Shaw Unknown Date (has links)
本篇論文試圖藉由比較一個產業生產技術為固定規模報酬的經濟體系,如何因外部因素的影響而改變其動態調整方式。在此考慮的外部因素有資本移動的開放與否、生產要素的外部性、及政府對要素報酬的課稅。考慮各種因素後,所得出的結論為在生產函數為Cobb-Douglas型式且產業生產技術為固定規模報酬的情況下: 1.多重均衡路徑在資本帳封閉時期唯有效用函數為特例時才能使其出現,但在資本自由移動時期對於所有的效用函數型態皆會成立。 2.其他條件保持不變之下,單獨存在生產要素外部性或是對要素所得課稅皆可使體系存在多重均衡路徑。 3.其他條件保持不變之下,若生產要素外部性與要素所得稅皆同時存在時,可使體系存在唯一的穩定馬鞍路徑。
98

伴隨估計風險時的動態資產配置 / Dynamic asset allocation with estimation risk

湯美玲, Tang, Mei Ling Unknown Date (has links)
本文包含關於估計風險與動態資產配置的兩篇研究。第一篇研究主要就當須估計的投資組合其投入參數具有高維度特質的觀點下,探究因忽略不確定性通膨而對資產配置過程中帶來的估計風險。此研究基於多重群組架構下所發展出的新投資決策法則,能夠確實地評價不確定性通膨對資產報酬的影響性,並在應用於建構大規模投資組合時,能有效減少進行最適化投資決策過程中所需的演算時間與成本。而將此模型應用於建構全球ETFs投資組合的實證結果則進一步顯示,若在均值變異數架構下,因建構大型投資組合時須估計高維度投入參數而伴隨有大量估計風險時,參數估計方式建議結合採用貝氏估計方法來估算資產報酬的一階與二階動差,其所對應得到的投資組合樣本外績效會比直接採用歷史樣本動差來得佳。此實證結果亦隱含:在均值變異數架構下,穩定的參數估計值比起最新且即時的參數估計資訊對於投資組合的績效來得有益。同時,若當投入參數的樣本估計值波動很大時,增加放空限制亦能有利投組樣本外績效。 第二篇文章則主要處理當處於對數常態證券市場下時,投資組合報酬率不具有有限動差並導致無法在均值變異數架構下發展出最適化封閉解時的難題。本研究示範此時可透過漸近方法的應用,有效發展出在具有放空限制下,考量了估計風險後的簡單投資組合配置法則,並且展示如何將其應用至實務上的資產配置過程以建構全球投資組合。本文的數值範例與實證模擬結果皆顯示,估計風險的存在對於最適投資組合的選擇有實質的影響,無估計風險下得出的最適投資組合,不必然是存有估計風險下的最適投資組合。此外,實證模擬結果亦證明,當存有估計風險時,本文所發展的簡單法則,能使建構出的投資組合具有較佳的樣本外績效表現。 / This dissertation consists of two essays on dynamic asset allocation with regard to dealing with estimation risk as being in different uncertainties in the mean-variance framework. The first essay concerns estimation errors from disregarding uncertain inflation in terms of the need in estimating high-dimensional input parameters for portfolio optimization. This study presents simplified and valid criteria referred to as the EGP-IMG model based on the multi-group framework to be capable of pricing inflation risk in a world of uncertainty. Empirical studies shows the proposed model indeed provides a smart way in picking worldwide ETFs that serves well to reduce the amount of costs and time in constructing a global portfolio when facing a large number of investment products. The effect of Bayesian estimation on improving estimation risk as the decision maker is subject to history sample moments for input parameters estimations is meanwhile examined. The results indicate portfolios implementing the Stein estimation and shrinkage estimators offer better performance compared with those applying the history sample estimators. It implicitly demonstrates that yielding stable estimates for means and covariances is more critical in the MV framework than getting the newest up-to-date parameters estimates for improving portfolio performance. Though short-sales constraints intuitively should hurt, they do practically contribute to uplift portfolio performance as being subject to volatile estimates of returns moments. The second essay undertakes the difficulty that the probability distribution of a portfolio's returns may not have finite moments in a lognormal-securities market, and thus leads to the arduous problem in solving the closed-form solutions for the optimal portfolio under the mean-variance framework. As being in a lognormal-securities market, this study systematically delivers a simple rule in optimization with regard to the presence of estimation risk. The simple rule is derived accordingly by means of asymptotic properties when short sales are not allowed. The consequently numerical example specifies the detailed procedures and shows that the optimal portfolio with estimation risk is not equivalent to that ignoring the existence of estimation risk. In addition, the portfolio performance based on the proposed simple rule is examined to present a better out-of-sample portfolio performance relative to the benchmarks.
99

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
100

員工正向情緒表達影響因素之研究: 交易層次分析與個人變數之 跨層次干擾效果 / Exploring antecedents of positive affective displays: The examinations of within-person and between-person moderating effects of employee characteristics

陳皓怡, Chen, Hao Yi Unknown Date (has links)
過去探討影響員工正向情緒表達之前因的實證研究,已累積相當豐富,但在前因變數間之交互作用,以及情緒表達概念上,仍有以下兩大類議題尚未處理:首先,鮮少研究同時探討個體內層次 (交易層次)與個體間層次 (員工個人層次)之跨層次研究,即檢視單一員工服務多位顧客時之巢狀的影響 (nested effects),故本研究提出的理論模型包含兩個層次變數之間的關係:個體內層次 (交易忙碌程度、顧客負向情緒表達)與個體間層次 (知覺工具型主管支持、知覺情感型主管支持、情緒穩定性特質),以試圖彌補此研究缺口。再者,過去有關情緒表達之研究,大多探討員工於每筆交易時所展現之正向情緒表達之強度,因此,本研究另一個研究興趣探討員工個人變數與員工正向情緒表達之平均強度間的關係。 本研究以76位中華郵政第一線儲匯服務人員,及與其互動之434位顧客為研究對象,階層線性模式分析結果發現顧客負向情緒表達與員工正向情緒表達具有顯著負向關係;而在員工個人變數之跨層次干擾效果探討上,本研究結果發現,當員工知覺工具型主管支持較高時,會削弱顧客負向情緒表達與員工正向情緒表達之間的負向關係;且當員工情緒穩定性特質較高時,也會使交易忙碌程度與員工正向情緒表達間之負向關係減弱。最後,階層迴歸分析結果亦指出員工知覺情感型主管支持與員工正向情緒表達之平均具有顯著正向關係。整體而言,本研究所提之研究假說部分符合理論預期,而研究結果可對情緒表達、情緒勞動、與社會支持相關研究提供理論貢獻與實務意涵。 / Although most of previous studies have explored the antecedents of employee positive affective displays, the issues of examining the main effects of transaction cues and the moderating effects of employee characteristics on employee positive affective displays from the perspective of within-person and between-person analysis remain relatively unexplored so far. Therefore, this study examined whether transaction defining cues (ex., transaction busyness and client negative affective displays) affected employee positive affective displays. Besides, this study examined whether employee characteristics would moderate the relationships between transaction defining cues and employee positive affective displays. Results from 76 postal clerks of 32 post offices and 434 clients partially supported our hypotheses and showed that client negative affective displays negatively predict employee positive affective displays. With regard to the moderating effects of employee characteristics, when the postal clerks perceived high level of supervisor instructmental support, the negative effect of client negative affective displays on employee positive affective displays was minimized. Moreover, employee with high level of emotional satbility would weaken the negative relationship between transaction busyness and employee positive affective displays. In addition, the study also indicate that employee perceived high level of supervisor emotional support would increase the employee average performance of positive affective displays. In conculsion, these findings provide not only further understanding how to improve employee affective displays, but also guidance for the organizations to select and train appropriate emoployees.

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