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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.
1

線性規劃於煉油廠原油選擇應用之研究

洪裕政 Unknown Date (has links)
原油成本幾乎占煉油廠經營總成本的90%以上,因此降低原油採購成本是煉油廠降低成本與增加效益的重要途徑。從國際原油交易市場觀點,我國是全部原油進口國家之一,尤其石油產業競爭從1960年代起,多次石油危機更影響世界政治和經濟發展的重要資源。2004年來,隨著國際油價大漲,石油能源需求及煉油產業經營已成為全球重要的課題。因此我國依石油管理法進行開放國內外油品市場之際,已就國家原油量的供需進行國家原油儲油計劃及實施,並提升國家安全庫存需求,同時也因應原油與成品油國際價格變動,積極開拓採購原油油源。目前國際化趨勢營運之煉油產業對我國而言是挑戰開端,主導掌控原油市場脈動,強化管理,優化生產,降低成本等是重要指標。 本研究相關之線性規劃(Linear Programming,LP)應用於原油選擇之生產計劃已成為處理煉油業經營管理的主要手段之一。本研究以某煉油廠作案例,探討原油選擇最佳化採購主因,利用線性規劃模型建立制定製程單元合理的生產操作條件,充分發揮單元的潛能,是執行工廠效益最佳化的基本條件。但單元操作條件的調整牽涉到煉油廠整體原油物料流程的相關變化,包括成品油產品結構、製程單元限制、公用流體消耗等各方面。運用原油物料性質的自動傳遞、分散式遞迴方法,遞迴出原油性質或產品性質收率之間的關聯以得到原油選擇最佳化結果。 本研究之主要研究成果如下: (1) 建立煉油廠製程單元模型最佳化之原油選擇應用方式。 (2) 建立煉油廠原油選擇後生產計劃決策模式。 / In the oil refinery, the crude oil cost almost takes above 90% of the total cost, so reduce the crude oil purchasing cost is an important method for the oil refinery to reduce the cost and increase the benefit.In the market view of international crude oil trade, ROC is one of the countries that nearly all rely on importing for the crude oil demand. Since the competition of petroleum industry begins from 1960’s and the experiences go through several petroleum crisis make the petroleum to be the important resource influence the world politics and economy development. The price of international crude oil go up quite substantially since 2004, the petroleum energy demand and oil-refining industry managements have become the global important topic. So when the government depends on the petroleum management law to open the domestic and international petroleum product market, she both considers the supply and demand of national crude oil quantity to build the national plan in the crude oil storage and implement, and promote the national security stock demand. To respond the crude oil and finished product oil international prices fluctuation, she also expands actively the crude oil source to buy. The internationalization operation in the oil-refining industry is just a beginning of challenge for our country. To control the crude oil market pulsation, enhance the management, optimize the production, reduce the cost etc. is an important index sign. The Linear Programming (LP) applies in the crude oil selection for the production plans become the one of the main management means in the oil-refining industry. To instance the oil refinery and find out the main factor to optimize the purchasing cost in the crude oil selection. To utilize the linear programming model to set up the reasonable operation conditions of the process units and develop the potential of the unit well is the essential condition that implements the factory benefits optimization. But the adjustment about the operation conditions of the process units concern with the related variety of the whole crude oil and material process in the oil refinery, including the kinds of finished product oil, the process unit restriction, the consumption of utility fluid etc. To make use of the automatic communication of the crude oil properties and distributed recursion to point out the relationship between the crude oil property and the product property yield, the optimization results from crude oil selection. (1) To establish the application method of crude oil selection optimization of the oil refinery process unit model. (2) To establish the decision mode of production plan after the crude oil selection of the oil refinery.
2

台灣地區匯率影子價格之研究

饒方敏, RAO, FANG-MIN Unknown Date (has links)
本篇論文共一冊,文中計分五章:第一章為緒論,旨在說明研究目的與本篇論文結構 。第二章則為文獻回顧部份,說明不同的計算匯率影子價格之方法。第三章則在建立 一多部門的一般均衡模型,並使用Newton's iteration method 來求解此一般均衡型 之內生變數解。第四章則說明在求解過程中的資料處理,並且作比較靜態分析,設政 府自發性進口需求增加,對所有內生變數的影響,而將有關部份的變動代入計算匯率 影子價格的公式中,而求出台灣外匯的影子價格。最後一章,即第五章為結論,並提 出本文對未來改進方向之建議。另在最後加入附錄,說明有關之方程式及參數的估計 。
3

台灣地區有效財產稅率之推估

林詩堯 Unknown Date (has links)
我國的財產稅率雖然以法律條文明文規定各縣市的財產稅率一致,並不允許各地方政府依照自己地方的自然環境特徵、政治、人文偏好,訂立差異化的財產稅率以符合地方自己財政的需求。有違憲法所賦予的『地方自治精神』和理論上地方財政的租稅競爭均衡。可是事實上,在我國稅法上,計算財產稅的倍數累進稅基基準,各縣市政府都不同。在課徵土地增值稅時是依照各縣市官方所發佈的『土地公告現值』作為計算的稅基基準;課徵地價稅是依照各縣市的『公告區段地價』作為稅基;課徵房屋稅是依據各縣市政府所評定的『房屋評定現值』作為課徵基礎。可是由於各縣市都市化程度不同,所以各縣市間的公告現值、公告地價和房屋評定現值差異很大,再加上地價稅各縣市間的倍數累進課徵起點都不相同以及課稅的評估價值與市價的差距,如此一來,使的各地土地交易所需負擔的有效土地增值稅賦、持有土地所課征的有效地價稅率及持有房屋的有效房屋稅率各縣市間均有顯著的不同。本文嘗試從個體交易資料分別推估台灣各縣市對於持有土地、房屋時所需實質承當的有效稅率。藉此來釐清各縣市間雖然有一致的『名目』財產稅率,可是實際上各縣市人民所需承受的『實質』『影子價格』是不同。此外,在推估台灣地區財產的有效稅率後,本文藉由比較國際間各國財產的有效稅率,說明台灣地區財產有效稅率有明顯低落的現象。本文估計出實際上台灣地區住宅區有效地價稅率的約為0.0243%、住宅區有效房屋稅約為0.2252%。而地價稅的有效估價率約為0.12,低於房屋稅的估價率0.23。從區域分佈及各縣間分佈來分析,發現房屋稅較地價稅分佈更符合租稅課徵的公平和效率。   此外,整體來看,有效地價稅率是呈現『先累退,在逐漸累進』的現象。至於23個縣市間,地價稅的累進、累退或一致性則呈現相當分歧的結果。
4

探討半參數隨機邊界模型的技術與配置效率之一致性估計方法 / Consistent estimation of technical and allocative efficiencies for a semiparametric Stochastic Cost Frontier with Shadow Input Prices

陳冠臻, Chen, Kuan Chen Unknown Date (has links)
傳統參數隨機成本邊界模型需事先假設其函數型態,但真正的函數型態未知,若是假設錯誤的函數型態可能存在模型設定誤差,另外過去估計成本函數時,大多著重於技術效率的衡量,而忽略配置效率,如此一來,將導致模型參數估計產生偏誤,影響後來效率的計算。基於上述的問題,本研究將應用半參數隨機成本邊界模型且同時考量技術效率與配置效率,不但函數設定具有彈性且能正確的衡量效率值,然而在考量配置效率的衡量後,增加模型估計的困難度,使得估計收斂不易,因此本研究提出一個五階段的估計步驟,應用蒙地卡羅模擬進行分析,該估計步驟不但能簡化估計且能得到技術與配置效率的一致性估計。最後則將本研究提出的估計方法應用在實證研究上,探討14個東歐國家在轉型期間其技術與配置效率的衡量,使用不平衡縱橫資料,共340家商業銀行進行實證分析。 / Conventional parametric stochastic cost frontier models are likely to suffer from biased inferences due to misspecification and the ignorance of allocative efficiency (AE). To fill up the gap in the literature, this article proposes a semiparametric stochastic cost frontier with shadow input prices that combines a parametric portion with a nonparametric portion and that allows for the presence of both technical efficiency (TE) and AE. The introduction of AE and the nonparametric function into the cost function complicates substantially the estimation procedure. We develop a new estimation procedure that leads to consistent estimators and valid TE and AE measures, which are proved by conducting Monte Carlo simulations. An empirical study using unbalanced panel data on 340 commercial banks from 14 East European countries over the period 1993-2004 is performed to help shed some light on the usefulness of our procedure.

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