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Decomposition of Lagrangian classes on K3 surfaces
Get PDFWe study the decomposability of a Lagrangian homology class on a K3 surface into a sum of classes represented by special Lagrangian submanifolds, and develop criteria for it in terms of lattice theory. As a result, we prove the decomposability on an arbitrary K3 surface with respect to the Kähler classes in dense subsets of the Kähler cone. Using the same technique, we show that the Kähler classes on a K3 surface which admit a special Lagrangian fibration form a dense subset also. This implies that there are infinitely many special Lagrangian 3-tori in any log Calabi-Yau 3-fold.https://arxiv.org/abs/2001.00202Othe
Synthesis, Characterization, and Application of Nanostructured Silica Materials
No full text此論文主要以二氧化矽材料作為主軸，依結構與應用上的不同，此論文內容分成四個主題；第一個部份為骨架含稀土元素(釔, 釓, 鋱)的中孔洞奈米顆粒的合成、鑑定與應用，由於近年來核磁共振造影已成為臨床醫療診斷上的重要工具之一，其中核磁造影對比劑方面的研究更是此領域相當重要的一部分，而此研究特點便是將釓金屬離子嵌在中孔洞材料的骨架上，來增強其對水的鬆弛率，進一步增強影像的對比；此結果使中孔洞材料不但具有其本身的特點，如高表面積、孔洞一致性等，亦提供做為核磁造影對比劑應用上的可能性，並利用此材料做為核磁共振影像追蹤劑，並應用到藥物的釋放上。第二部份是合成殼層結構的奈米顆粒，此部份我們成它b鹼性下合成出含有稀土元素的殼層結構氧化矽材料，其殼的部份由稀土元素的氫氧化物組成如氫氧化鋱、氫氧化釔，此外並可控制包覆在殼外層氧化矽的厚度，此殼層結構的膠體粒子具有相當好的顆粒大小分布均勻性，此外由於稀土元素其特殊的放光性質與一般傳統染料具有相當寬的放光波帶，另外可藉由不同的稀土元素作為殼，即可調變不同的放光波段，由於此殼層結構氧化矽球大小的一致性，便可作為形成光子晶體的建構單元，往後的發展著重在進一步探討發光元素在光晶中的特殊光學性質。第三部份為製備具有六方堆積孔洞規則性結構與大小均勻的奈米顆粒，並同時在此氧化矽奈米顆粒的骨架嵌入染料分子作為螢光影像追蹤劑，將此中孔洞奈米顆粒與老鼠的纖維組織母細胞同時培養，並利用共軛焦顯微鏡可進一步發現此中孔洞奈米顆粒可進入老鼠的纖維組織母細胞內，並主要分布積聚在細胞膜內，表示此奈米級中孔洞材料可被細胞吞噬進入細胞，此結果顯示中孔洞材料在藥物分子儲存與釋放上具有相當的發展潛力。第四部份，主要是著重在一般較為傳統孔洞材料的合成，此部份我們成孕H簡單的共界面活性劑方法合成孔洞介於一奈米與兩奈米間並具有相當規則的六方堆積孔洞材料，一般稱為super-microporous silica，此小孔洞的材料在表面氣體吸附行為的研究與分子形狀選擇性的催化反應上具有相當的應用潛力。My research goal is exploring new properties for silica based materials. In this thesis, the topics are divided into four sections: (i) lanthanide incorporated nanosized mesoporous silica and the potential as MRI contrast agent, (ii) synthesis and characterization of lanthanide hydroxide@silica colloidal sphere, (iii) well-ordered mesoporous nanoparticle and the potential in biological application, and (iv) simple synthesis of well-ordered super-microporous aluminosilicate.
In the first part, we have successfully synthesized Ln(III) incorporated mesoporous silica nanoparticels (Ln-MS) by acid-to-base and high dilution method. In addition to the inherent properties of mesoporous silica, the Gd-MS porous silica exhibits an additional ability on the enhancement of water proton relaxation. We believe these materials may be useful in biological tracking and imaging applications. In the second part, we have synthesized monodisperse lanthanide hydroxide@silica core sphere in base condition. The monodisperse core-shell spheres are promising to serve as building blocks to fabricate photonic crystals for further optical investigations. In the third part, we have demonstrated for the first time that the mesoporous silica nanoparticles can translocate into cell and have no short term toxicity on the cell; hence, open up an exciting field of mesoporous silica in biomedical applications. In the fourth part, we have provided a simple method for the synthesis of highly ordered super-microporous aluminosilicates by using co-surfactant system. We expect the materials to be useful in catalysis and gas adsorption studies. All in all, we have demonstrated the great potential of mesoporous and spherical silica nanoparticles in the exciting biomedical field.Section One Introduction to Nanostructured Silica Materials.................................................1
1.1 Mesoporous Materials..................................1
1.1.1 Brief Description of Mesoporous Materials...........1
1.1.2 Mesoporous Silica in Biological Application.........3
1.2 Core-shell Structured Materials.......................5
1.3 References............................................8
Section Two Lanthanide Incorporated Mesoporous Nanoparticles and the Potential as MRI Contrast Agent....10
2.1 Background and Introduction..........................10
2.2.1 Background.........................................10
2.2.2 Introduction.......................................15
2.2 Experimental Section.................................17
2.2.1 Materials..........................................17
2.2.2 Synthesis Procedure................................18
2.2.3 Characterization...................................18
2.3 Results and Discussion...............................20
2.4 Conclusion...........................................38
2.5 References...........................................39
Section Three Synthesis and Characterization of Lanthanide Hydroxide@Silica Core-Shell Colloidal Sphere.............41
3.1 Introduction.........................................41
3.2 Experimental Section.................................43
3.2.1 Materials..........................................43
3.2.2 Synthesis Procedure................................44
3.2.3 Characterization...................................44
3.3 Results and Discussion...............................45
3.4 Conclusions..........................................65
3.5 References...........................................66
Section Four Well-Ordered Mesoporous Nanoparticles and the Potential in Biological Application......................69
4.1 Introduction.........................................69
4.2 Experimental Section.................................72
4.2.1 Materials..........................................72
4.2.2 Synthesis of Mesoporous Nanoparticles..............72
4.2.3 Cell Uptake Assay..................................74
4.2.4 Characterization...................................74
4.3 Results and Discussion...............................75
4.3.1 Synthesis and Characterization of Mesoporous Silica Nanoparticles............................................75
4.3.2 Cell Uptake of Mesoporous Silica Nanoparticles.....85
4.4 Conclusion...........................................90
4.5 References...........................................91
Section Five Simple Synthesis of Well-Oredered Super-Microporous Aluminosilicate..............................93
5.1 Introduction.........................................93
5.2 Experimental Section.................................95
5.2.1 Materials..........................................95
5.2.2 Synthesis Procedure................................95
5.2.3 Characterization...................................96
5.3 Results and Discussion...............................97
5.4 Conclusion..........................................106
5.5 References..........................................107
Figure Index:
Fig.1.1...................................................1Fig.1.2...................................................2
Fig.1.3...................................................3
Fig.1.4...................................................4
Fig.1.5...................................................5
Fig.1.6...................................................6
Fig.1.7...................................................7
Fig.2.1..................................................11
Fig.2.2..................................................11
Fig.2.3..................................................12
Fig.2.4..................................................13
Fig.2.5..................................................15
Fig.2.6..................................................24
Fig.2.7..................................................24
Fig.2.8..................................................26
Fig.2.9..................................................27
Fig.2.10.................................................30
Fig.2.11.................................................31
Fig.2.12.................................................32
Fig.2.13.................................................32
Fig.2.14.................................................35
Fig.2.15.................................................36
Fig.2.16.................................................37
Fig.3.1..................................................47
Fig.3.2..................................................49
Fig.3.3(A)...............................................50
Fig.3.3(B)...............................................50
Fig.3.3(C)...............................................51
Fig.3.3(D)...............................................51
Fig.3.3(E)...............................................51
Fig.3.3(F)...............................................52
Fig.3.4..................................................53
Fig.3.5..................................................56
Fig.3.6(A)...............................................56
Fig.3.6(B)...............................................57
Fig.3.6(C)...............................................57
Fig.3.6(D)...............................................58
Fig.3.7..................................................59
Fig.3.8..................................................60
Fig.3.9..................................................61
Fig.3.10.................................................62
Fig.3.11.................................................62
Fig.3.12.................................................64
Fig.4.1..................................................78
Fig.4.2..................................................79
Fig.4.3..................................................81
Fig.4.4..................................................82
Fig.4.5..................................................82
Fig.4.6..................................................83
Fig.4.7..................................................83
Fig.4.8..................................................83Fig.4.9..................................................87
Fig.4.10.................................................88
Fig.4.11.................................................89
Fig.5.1..................................................98
Fig.5.2..................................................99
Fig.5.3.................................................102
Fig.5.4.................................................103
Fig.5.5.................................................105
Fig.5.6.................................................105
Table Index:
Table 2.1 Structural and textural data of X%Gd-MS........25
Table 2.2 Relaxivities of Gd-MS at 9.4T..................33
Table 2.3 Relaxivities of Gd-MS at 0.47T.................33
Table 2.4 Relaxivities of Eu-Gd-MS at 9.4T...............34
Table 3.1 Measured PL lifetimes of core-shell spheres....61
Table 4.1 Structural and textural data of mesoporous silica nanopparticles....................................84
Table 5.1 Structural and textural data of calcined C10MS porous silica...........................................101
Scheme Index:
Scheme 2.1..............................................21
Scheme 2.2..............................................29
Scheme 4.1..............................................77
Scheme 4.2..............................................8
A Case Study on Diversified Growth and Corporate Transformation
No full text面對IT產業的結構性變化，台灣電子科技業面臨殘酷的淘汰賽，身處其中的企業更面臨轉型變革的壓力，如何利用自身的優勢，採取有效的策略活動把自己變強變大，尋求多角化的成長，以降低產業變動的風險，成為本研究想要探討的核心議題。 為回答此一問題，本研究進行了個案式的研究，針對選取的個案企業，藉助產業分析、核心能力與商業模式的理論框架，首先發展並定義該公司的核心產品，並回頭檢視原有能力組合是否足夠應付新的核心產品所需。本研究同時探討該企業建立新的核心能力時，如何檢視調整公司的既有文化價值觀、組織架構與工作方法，以確保變革的成功。 本研究發現，企業當遇到產業結構調整時，必須重新檢視自己的核心能力，是否能延伸出新產品與新市場機會，這是最容易成功且省成本的做法，再其次才是開發新核心能力，因為，建立新核心能力至少要三年，必須有足夠的資金與時間。 同時，當組織開始有能力建立不同核心產品、面對不同市場及產業時，為達有效的資源管理，組織的分工結構就必須調整。建立企業總部與事業部的專業分工，以確保運作順利、產生綜效，並借助企業總部的有效運作，扶持新的事業部，不斷拉出新的成長曲線，方能提高企業多角化成長的成功機會。The global IT industry has experienced significant structural change due to technology paradigm shift. As the manufacturing powerhouse for the IT industry globally, Taiwanese electronics industry is therefore facing a huge pressure of transformation..How can an industry player maintain its competence to survive from sever competition in the existing market while explore new growth opportunities in unfamiliar areas? Such strategic and organizational challenges motive the present thesie research. To achieve our research goals, we conduct a case-based exploration. Guided by several existing theoretical insights, such as industry analysis, core competency, and businesss model design, we study the processes of competence leverage and renewal occurred in the case company during the past years. In addition, we also examine how the company change its organization structure, processes and corporate culture to align with its new business configuration so that the transformation can reach its desired goals. Throughout the case exploration, we found that a firm has to immediately examine its sustainability of the existing core competencies when facing structural change. Priority issue will be to see if the existing core capabilities could be extended to capture new opportunities, which will be the most cost effective way of diversified growth. The next feasible alternative will be to invest in developing new competencies since it may take at least three years to create new competencies. While in the process of competence renewal, the organization has to ensure its internal managerial coherence by designing new divison of labor and managing synergies between new and existing businesss units. The establishment of corporate headquarters become critical to the success of corporate transformation. Only by constantly drive new growth curves can a company successfully adapt to external changes
A study of volunteer interpreter system in the Taipei Wild Bird Society
No full text民間團體在政府與民眾間扮演著橋樑、媒介的重要角色，發揮傳播、協調、整合的功能，協助各種工作的完成。台北鳥會為國內迭有聲名且具歷史的保育團體，其擁有為數眾多的解說義工，提供解說服務與推廣環境教育工作，在自然保育和環境教育扮演著積極重要的角色。本研究以台北野鳥學會為個案，主要採取質性研究法，以參與觀察、非正式訪談及深度訪談等方式收集資料，並將田野收集到的相關資料譯碼分析，來研究台北鳥會的解說義工制度，以探討瞭解保育團體的義工招募、培育與運用。
本研究義工義工義工義工發現台北鳥會義工透過「帶隊解說」培養實務經驗；參與「鳥會舉辦解說活動」；「野外賞鳥觀察」進行野鳥辨識和生態觀察；持續提供「進修課程」給解說義工進修機會；閱讀書本，自修方式，來養成解說義工的專業能力。義工義工扮演推廣鳥會理念的角色；協助鳥會的代辦解說服務，收集來自民間、政府和企業的資源；同時節省鳥會人力成本；協助組織的義工管理；培育鳥會未來的義工等。而透過團隊職務安排，資深和資淺搭配制度；持續培訓課程和義（志）工經驗分享；刊登解說義工「姓名」，由義工建立自己的解說品牌特色，來控管解說的品質。在義（志）工的組織管理上，台北鳥會每年辦理冠羽班持續培養義（志）工，而以班級為單位除有效推動認養服務工作外，對志（義）工彼此情感的維繫也大有助益。另外，台北鳥會也會適時公開表揚志（義）工，從滿足其成就感與歸屬感需求，來維繫會裡的志（義）工。Non governmental organizations can play as the bridge and medium between the government and the people to communicate and negotiate each other, integrate resources and to make many work done. The Taipei Wild Bird Society is a famous domestic conservation organization of long history, and with plenty of volunteers on interpretation services and environmental education which is very crucial to natural conservation and environmental education in Taiwan. This study uses Taipei Wild Bird Society as a case study to study its volunteer interpreter system. It adopts qualitative methods, such as participant observation, informal interview and deep interview to collect field materials, and reassemble the storyline by coding the materials.
This study finds that the Taipei Wild Bird Society trains the volunteer interpreters by assigning them being the guides of bird watching activities, participating activities, bird watching and ecological observation, joining advanced training courses and self-reading. These volunteers are those who sell the ideas and visions of Taipei Wild Bird Society. They can broaden the collection and competition of resources from the publics, industrial sector and the government for this society, save investments and costs of this society on operation, and assist it with managing and training volunteers. The ways for this society to control the quality of interpretation include, arranging works by groups, mixing senior and junior ones on duty, conducting continuous training courses, experiences sharing and posting names of interpreters on advertisement sheet to build up personal credits. In regards to volunteer organization and management, this society has training courses annually. The volunteers then can work and communicate with each other by the unit of the course. Also this society shall praise volunteers of excellence to satisfy the psychological demands and belongings of volunteers.目錄
第一章 續論 1
第一節 研究動機 1
第二節 研究方法 2
第二章 文獻回顧 9
第一節 保育團體與志願服務 9
第二節 志工管理制度 16
第三章 台北鳥會的介紹 25
第一節 鳥會的發展與組織介紹 25
第二節 解說地點及任務介紹 33
第三節 義工人力配置與分析 39
第四章 台北鳥會解說義工制度 50
第一節 義工的招募 50
第二節 解說義工訓練系統 53
第三節 解說義工運用 64
第五章 結論與討論 76
第一節 關於義工招募和來源 76
第二節 解說義工的培育 77
第三節 解說義工的運用 78
第六章 結論與建議 79
第一節 田野研究發現 79
第二節 研究限制和後續建議 84
引用文獻 86
附錄 9
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
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