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Two Methods for Solving Reservoir Goal Linear Programming and its Dual Problem
No full text本文以案例及圖表說明水庫標的線性規劃模式、對偶模式與原、偶二模式的關係。一個兼具蓄洪、供水與貯水三類服務功能的水庫，必須有足夠的容量，才能滿足各項預定需求，並假定各時期各功能服務的成本是供應量的片段線性函數。標的模式的對偶模式是提供替代服務的水庫同業訂定服務價格的問題：在水庫接受的條件下，如何決定價格參數使它提供的收益最高。
文中利用單純形法處理原始問題，用對偶單純形法求解水庫之對偶問題，原本求演算過程中的單位淨成本是針對切割各枝對其他弦的替換關係，在此轉而利用原、偶題間互補鬆弛條件的方法求得，經過比較更能增加演算效率。A reservoir goal linear programming model, its dual model and the relations among the two are introduced with simple examples. The three functional services of the reservoir considered are: reserved space for flood control, water supply, and pooling of water. The reservoir is to be operated to meet the minimum demands for each service item in each period. The profit for each service is a piecewise linear of the supply and their total profit from all service items is to be maximized or minimized.
First, potential network simplex was offered to solve reservoir problem. Then, flow network dual simplex was used to solve the dual problem. The key concepts of the two models and their simplex network algorithms are itemized in tables and compared for the duality.摘要 Ⅰ
Abstract Ⅱ
目錄 Ⅲ
表目錄 Ⅴ
圖目錄 Ⅵ
第一章 序論 1
1.1 前言 1
1.2 文獻回顧 2
1.3 章節介紹 2
第二章 水庫標的線性規劃問題 3
2.1 問題描述 3
2.2 水庫問題簡例 6
2.3 水庫標的線性規劃模式 11
2.4 水庫問題的規劃方案 14
第三章 水庫標的線性規劃問題之對偶問題 17
3.1 問題描述 17
3.2 水庫對偶線性規劃模式 20
3.3 對偶問題的價格方案 24
第四章 網絡單純形法 28
4.1 基本可行規劃方案及初始規劃方案 28
4.2 網絡單純形法演算 35
4.3 單純形法求解原始問題 46
第五章 網絡對偶單純形法 53
5.1 基本對偶可行價格方案及初始價格方案 53
5.2 網絡對偶單純形法演算 56
5.3 對偶單純形法求解對偶問題 61
5.4 單純形法與對偶單純形法比較 67
第六章 結論與建議 69
參考文獻 71
附錄A 對偶單純形法 73
附錄B 對偶定理 77
附錄C 互補鬆弛定理 78
附錄D 網絡單純形法 7
Enhancement of Java Numerical Computing Framework
No full textJava技術在數值運算上的改良已經被廣泛的討論，大致可區分為兩個類別：
Michael Philippsen and Edwin Ghnthner和Brian Blout and Siddhartha Chatterjee等人進行的計畫著重在利用新的Java 編譯器，或者更改Java語言來達到增進效能。
Peng Wu, Sam Midkiff, Jose Moreira and Manish Gupta、Jose E. Moreira, Samuel P. Midkiff and Manish Gupta等人進行的專案，則著重在修改VM並配合自定的函式庫來增進效能。
但無論是靠修改Java語言或是修改VM，都有其不可避免的優缺點。修改Java語言或class格式將失去Java本身跨平台的特性，而只修改VM而不配合修改編譯器，將會使它增加釵h額外的負擔來檢查執行時物件的狀態。到目前為止，仍然沒有一個完整的架構能整合Java編譯器及VM，因此我們在這裡提出一套讓Java編譯器和VM能更緊密配合的架構，來支援像數值運算這樣的特殊運算環境。
我們的概念是利用class格式裡面彈性的attribute設計，不需要更改Java語言，只需修改Java編譯器在class檔中加入有用的attribute資訊，並修改VM去讀取這些資訊並做對應的動作來提升整體的效率，如此一來我們不但能保有class跨平台的特性，也能省去VM在執行時的釵h負擔，增進效能。Enhancements of Java techniques on Numerical Computing have already undergone wide discussion. These attempts may be divided into two categories:
The works led by Michael Philippsen & Edwin Ghnthner, and Brian Blout & Siddhartha Chatterjee focus on improving Java through utilizing new Java compilers or modifying the Java language.
The research done by Peng Wu, Sam Midkiff, Jose Moreira & Manish Gupta, and Jose E. Moreira, Samuel P. Midkiff & Manish Gupta emphasizes performance enhancement through modification of Virtual Machine (VM), provided with self-defined class libraries.
However, despite the advantages of modifying Java or VM, they all have their own shortcomings. By altering the Java language or its class format, one risks losing the advantage of cross-platform portability, which is an important trait of Java. By altering only the VM but not the compiler, one would have to put more work into examining the status of objects at execution time. Until now there has not been a complete architecture capable of integrating Java compiler and VM, and it is the reason why we shall present a set of infrastructure that will bind the compiler and VM more closely so that they could support special computing environments such as numerical computing.
Our concept is to use the flexible attribute designs in the class format to keep the Java language unaltered, and to change only the Java compiler so that it would add useful attribute information to the class file during compilation. Then, we modify the VM to read in the information and to react correspondingly. In this way, we not only preserve class portability, but also free VM from excess status judgment at execution time, which greatly improves its performance.Chapter 1 - Introduction......................1
Chapter 2 - Java Performance Difficulties.....4
2-1 Complex Issue...........................4
2-2 Array Issue.............................8
Chapter 3 - JNC Framework....................13
3-1 Java Numerical Computing Framework.....13
3-2 DAXPY Attribute........................15
3-3 Array Attributes.......................19
3-2 Complex Attributes.....................27
Chapter 4 - Implementation...................33
Chapter 5 - Experimental Results.............36
5-1 Seven Simple Programs..................36
5-2 Java Linpack...........................42
Chapter 6 – Conclusions and Future Works....48
6-1 Conclusions............................48
6-2 Future Works...........................49
References...................................51
Appendix.....................................5
Effects of PM Processing Parameters and Alloying Elements on the Magnetic Properties of Sintered Iron Powders
No full text乾壓成形與金屬射出成形之純鐵與鐵基合金軟磁零件，已廣泛地應於各項電子產品中，隨著電子產品的小型化，更凸顯粉末冶金製程在製造小型且形狀複雜之零件時，產量較高且成本較低的優勢，但由於製造過程中有添加高分子黏結劑，因此產品的雜質含量需要特別控制以獲得良好的磁性質。本實驗選用四種羰基鐵粉，測量在不同升溫速率、燒結溫度及燒結氣氛的情況下，純鐵燒結後之磁性質表現；本實驗也在純鐵粉中添加數種常用之合金元素，並使用工業界常用之燒結製程參數，以探討製造軟磁零件之可行性。
實驗結果發現，熱脫脂時之升溫速率對羰基鐵粉燒結後的磁性質有很大的影響，以不含SiO2之羰基鐵粉為例，熱脫脂過程中以3 ℃/min速率升溫之乾壓成形試片，於1350℃裂解氨氣氛下燒結一小時後，其磁性質與以5 ℃/min速率升溫之試片相比時，矯頑磁力減少13%且最大導磁率增加45%，分別達到141 A/m與3880。實驗結果也發現，在純鐵中添加合金元素後，對於熱脫脂過程之升溫速率可能變得更加敏感，以Fe-3 wt% Si為例，熱脫脂過程中以3 ℃/min速率升溫之乾壓成形試片，於1350℃裂解氨氣氛下燒結一小時及在真空中燒結兩小時後，其磁性質均不理想，但降低升溫速率至2 ℃/min時，試片之飽和磁束密度提升15%，矯頑磁力減少60%，最大導磁率增加60~70%。
本實驗結果顯示，不含SiO2且粒徑較小(D50=4μm)之羰基鐵粉，以乾壓成形，並以3 ℃/min之升溫速率於裂解氨氣氛中進行熱脫脂，再於1350℃裂解氨氣氛中燒結一小時，其密度達到7.45 g/cm3，以最大外加磁場1990 A/m測量時，飽和磁束密度為1.51 Tesla，殘留磁束密度為1.29 Tesla，矯頑磁力為141 A/m，最大導磁率為3880，為本實驗磁性質最佳之純鐵材料。本實驗也比較了含有2 wt%、8 wt%及50 wt% Ni之鐵鎳合金，以及Fe-49Co-2V合金的磁性質，其中Fe-50 wt% Ni之導磁率最佳為13467，而Fe-49Co-2V之飽和磁束密度最佳為1.86 Tesla。Iron and iron-base alloys made by Press and Sinter (P/S) process and Metal Injection Molding (MIM) process, are now widely used in a variety of electronic applications. The advantages of P/S and MIM parts include high yield and low cost. However, due to the polymeric binder added to the green parts, impurity level could be too high to achieve good magnetic properties. Four kinds of carbonyl iron powders are used in this study. The magnetic properties are measured after sintering in different heating rates, sintering temperatures and sintering atmospheres. Iron-base soft magnetic alloys are also examined in this study. The alloys are sintered using industrial production parameters to demonstrate its practicability.
The results showed that magnetic properties are greatly influenced by the heating rate during thermal debinding. For the carbonyl iron powder without containing SiO2, when compacted and then sintered at 1350℃ in cracked ammonia for one hour, the coercivity decreased by 13% and permeability increased by 45% after decreasing the heating rate from 5 ℃/min to 3 ℃/min during thermal debinding, and reached
141 A/m and 3880, respectively. Similar behavior is shown in Fe-3 wt% Si alloys, when P/S Fe-3 wt% Si parts are sintered at 1350℃ in cracked ammonia for one hour and at 1350℃ under vacuum for two hours, the maximum induction increased by 15%, the coercivity decreased by 60%, and the permeability increased by 60~70%, when the heating rate is decreased from 3 ℃/min to 2 ℃/min.
The best magnetic properties of P/S iron was obtained using OM powder and using a heating rate of 3 ℃/min for thermal debinding and sintering at 1350℃ in cracked ammonia for one hour. The properties were Bs=1.51 Tesla, Br=1.29 Tesla, Hc=141 A/m, and μmax=3880
The Key Successful Factors of Jewelry Manufacturers in Taiwan — An Example of B Co.
No full text台灣珠寶飾品製造業一直以來都是扮演產業中螺絲釘的角色，而且習慣默默隱身在幕後；但實際上，他們對產業的根本及產業未來的發展都很重要，台灣金工技術在世界上並不會落後人家，只是台灣優秀的金工人才得不到專業上的肯定與社會認同，也讓他們的價值難以凸顯。
本論文的撰寫，希望能讓大家更了解台灣珠寶飾品製造業的生態，同時將整個產業上下游的串聯作一個簡單介紹，讓大家在配戴珠寶飾品的同時，可以稍微對這些珠寶飾品的來源有一些概念，知道每件產品背後，都有辛苦工匠的努力，才能成就每一件美麗的工藝作品。
透過對個案公司的關鍵成功因素作分析，我們看到台灣珠寶飾品加工企業努力轉型的過程，他們以技術為本位，以誠信為信念，朝世界一級加工廠的製作技術邁進。並且希望能夠帶動台灣珠寶產業一起為產業的提升作努力，讓台灣的金工文化能永久傳承下去。The jewelry manufacturers always play an invisible but important role in Taiwan’s jewelry industry. Jewelry manufacturers usually stand behind the scenes; In fact, jewelry manufacturers are very important to the fundamentals and the future of the development of the jewelry industry. Although Taiwan owns world-class metalworking techniques, consumers often do not realize the market value of such talents because of the lack of professional and social recognition for metalworking experts.
This thesis aims to enhance consumers’ understanding of the jewelry manufacturing industry eco-system in Taiwan, including the linkages of its upstream and downstream sectors. If consumers acquire some idea about the origin of the jewelries they wear, they may appreciate more about the hard-work of craftsmen in accomplishing the masterpieces behind the scenes.
Through the analyses of case studies, the report identified and analyzed key successful factors of Taiwan’s jewelry manufacturing industry, and the process of their industrial transformation. Based on technology and integrity, Taiwan’s jewelry manufacturers strive to acquire world-class manufacturing processing techniques, with the hope to jointly upgrade the Taiwan jewelry industry and ensure the sustainability of the metalworking cultural heritage in Taiwan.目 錄
目 錄............... v
表 目 錄.......... vi
圖 目 錄......... vii
第一章 緒論 1
第一節 研究背景 1
第二節 研究動機 3
第三節 研究問題與目的 4
第四節 研究方法與流程 5
第五節 論文架構 11
第二章 文獻探討 12
第一節 關鍵成功因素相關文獻探討 12
第二節 PEST分析 20
第三節 五力分析 23
第三章 外部環境分析 25
第一節 總體環境分析 25
第二節 產業環境分析 34
第四章 領導廠商個案分析 47
第一節 領導廠商背景介紹 47
第二節 顧客需求分析 50
第三節 個案公司關鍵成功因素的分析 56
第五章 研究結論與建議 60
第一節 研究結論 60
第二節 研究建議 62
第三節 研究限制 63
參考文獻........... 64
附錄................ 67
表 目 錄
表1-1：2012年7~12月來台旅客購物前五名排行榜...............................................2
表2-1：中外學者定義關鍵成功因素........................................................................12
表2-2：Leidecker & Bruno判斷關鍵成功因素的分析法........................................16
表3-1：近十年的平均每人所得與經濟成長率........................................................26
表3-2：台灣大專院校珠寶相關科系........................................................................29
表3-3：近十年台灣的結婚對數與結婚率................................................................31
表3-4：台灣各縣市珠寶業者統計表........................................................................35
表3-5：世界貴金屬合金成色規範............................................................................39
表3-6：台灣珠寶零售商經營型態分類表................................................................42
圖 目 錄
圖1-1：個案研究多重資料來源.................................................................................7
圖1-2：研究流程圖...................................................................................................10
圖1-3：論文架構.......................................................................................................11
圖2-1：辨識關鍵成功因素流程圖...........................................................................18
圖2-2：報酬率的拆解...............................................................................................19
圖2-3：五力分析架構圖...........................................................................................23
圖3-1：圖3-1 近十年經濟成長率折線圖..............................................................27
圖3-2：近十年平均每人所得折線圖.......................................................................27
圖3-3：近十年平均每人民間消費支出折線圖......................................................28
圖3-4：國人購買珠寶飾品動機調查......................................................................30
圖3-5：台灣的結婚年齡人口分布..........................................................................32
圖3-6：台灣珠寶產業供應鏈圖..............................................................................37
圖3-7：台灣珠寶零售商經營型態之簡易市場區隔圖..........................................42
圖3-8：台灣珠寶飾品加工業的五力分析圖..........................................................46
圖4-1：國人購買珠寶飾品的場所選擇..................................................................50
圖5-1：企業獲得成功的關鍵步驟圖......................................................................6
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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