마이크로미터 이하 패턴 제작을 위한 디지털 포토리소그래피 기술

학위논문(박사) -- 서울대학교대학원 : 자연과학대학 물리학과, 2021.8. 권여리.Digital photolithography based on digital micromirror device (DMD) is considered the next-generation low-cost lithographic technology. However, DMD-based digital photolithography has been implemented only for micrometer-scale pattern generation, whereas sophisticated photonic devices require feature sizes of submicron. In this thesis, we adopt a high-magnification imaging optical system for a custom-built digital photolithography system to generate submicron-scale patterns. We propose techniques to enhance the versatility of the digital photolithography, pattern tilting and grayscale exposure. We demonstrate that photonic crystal band-edge lasers of various lattice structures and periods can be quality-assessment testbeds. We also tried to enhance pattern uniformity. The experimentally determined pixel spread function predicted the exposure result well, which means that we can improve the pattern quality through preliminary correction.디지털 미세거울 장치에 기반한 디지털 포토리소그래피는 차세대 저비용 리소그래피 기술로 여겨진다. 그러나 디지털 미세거울 장치 기반 디지털 포토리소그래피는 주기가 1 마이크론 이상인 패턴 제작시에만 사용되었다. 광자결정레이저 등의 광소자 제작을 위해서는 패턴의 주기가 수백나노미터 수준이어야 하는데, 아직 디지털 포토리소그래피로 이러한 광소자를 제작한 사례는 없었다. 회절 한계를 계산해 보았을 때, 1 마이크론 이하 주기의 패턴 제작이 충분히 가능할 것으로 판단되어, 고배율 결상광학계를 활용하여 디지털 포토리소그래피 시스템을 구축하였다. 구축된 시스템을 사용하여 감광액이 코팅된 시편에 노광을 진행하였으며, 1 마이크론 이하 주기의 패턴 제작이 가능함을 보였다. 마이크로미터 이하 주기의 패턴을 제작할 때, 디지털 포토리소그래피의 패턴 설계 자유도를 향상시키기 위한 두 가지 방법인 패턴 기울임, 회색조 노광을 제안하였으며 실험적으로 시연하였다. 디지털 리소그래피 시스템의 검증에는 광자결정 띠 가장자리 레이저가 주로 사용되었는데, 레이저 발진 여부를 통해 노광 패턴의 품질을 파악할 수 있고 레이저 파장을 통해 노광 패턴의 주기를 파악할 수 있기 때문이다. 또한 픽셀 분산 함수를 도입하여 이미지의 회절 계산 및 패턴 품질 향상을 위한 밝기 보정을 제안하였다. 보정에 의해 패턴의 품질이 크게 향상되어, 전자빔 리소그래피로 제작한 것과 비교할 수 있는 수준이 되었다.Chapter1 Introduction 1 1.1. Photonic crystals 1 1.1.1. Introduction 1 1.1.2. Photonic crystal band-edge laser 4 1.1.3. Photonic crystal cavity laser 6 1.2. Conventional lithography techniques 8 1.3. Alternative lithography technique: digital photolithography 10 1.4. Outline of the manuscript 12 Chapter2 Submicron-scale digital photolithography 14 2.1. Introduction 14 2.1.1. Schematic of digital photolithography system 14 2.1.2. Proposed digital photolithography system 16 2.1.3. Pixel pitch at image plane 17 2.1.4. Resolving power of proposed digital photolithography system 19 2.2. Fabrication process of air-bridge photonic crystal 21 2.3. Square-lattice photonic crystal laser device 22 Chapter3 Fine-tuning the lattice constant: pattern tilting 26 3.1. Introduction 26 3.1.1. Wavelength division multiplexing application 26 3.1.2. Pattern tilting 28 3.1.3. All possible tilting configurations 30 3.2. Result and discussion 31 3.2.1. Tilting square-lattice 31 3.2.2. Tilting hexagonal-lattice 33 Chapter4 Fine structural tuning: grayscale exposure 36 4.1. Introduction 36 4.1.1. Implementation of gray pixel 36 4.2. Result and discussion 38 4.2.1. Grayscale exposed squre-lattice 38 4.2.2. Grayscale exposed hexagonal-lattice 41 Chapter5 Enhancing pattern uniformity 42 5.1. Introduction 42 5.1.1. Airy disk point spread function 42 5.1.2. Broadening factor and exposure dose profile 47 5.1.3. Experimental determination of broadening factor 49 5.2. Result and discussion 51 5.2.1. Diffraction simulation based on pixel spread function 51 5.2.2. Correction strategy 56 5.2.3. Analysis of correction result 58 Chapter6 Conclusion and perspective 61 References 63 Abstract in Korean 70박

Direct exfoliation of graphite using non-ionic polymer surfactant for fabrication of transparent and conductive graphene film

학위논문 (석사)-- 서울대학교 대학원 : 재료공학부, 2013. 2. 조원호.A high-yielding dispersion of graphene at high concentration in solvent is critical for practical applications. Herein, we demonstrate the formation of stable dispersion of pristine graphene in ethanol by exfoliating graphite flakes into individual graphene layers using a non-ionic polymer surfactant under bath-type sonication. Oligothiophene-terminated poly(ethylene glycol) was synthesized and used as a non-ionic and amphiphilic surfactant for exfoliating graphite into graphene. High-quality graphene film was fabricated from the exfoliated graphene solution by the vacuum filtration method. TEM and SEM reveal that the size of exfoliated graphene flake is larger than 1 m. When the graphene film was treated with nitric acid and thionyl chloride after washing with solvent, the film showed high performance with a sheet resistance of 0.3 kΩ sq−1 and a transparency of 74% at 550 nm.Chapter 1 Introduction 1 Chapter 2 Experimental 6 2.1 Materials 6 2.2 Synthesis 6 2.2.1 Synthesis of (2, 5-dibromo-thiophene-3-yl)-acetic acid (2Br-1TN) 6 2.2.2 Synthesis of 2Br-1TN-PEG 7 2.2.3 Synthesis of quinquethiophene-PEG (5TN-PEG) 7 2.3 Preparation of graphene solution 9 2.4 Fabrication of graphene film 9 2.5 Measurements 10 Chapter 3 Results and Discussion 12 3.1 Exfoiation and dispersion of graphene 12 3.2 Fabrication of graphene film 16 3.3 Chemical treatment of graphene film 23 3.4 Comparison of electro-optical property of our graphene film with other works reported in the literature 30 Chapter 4 Conclusions 37 Bibliography 38 Korean Abstract 43Maste

Fabrication of Transparent and Conductive Graphene Film from Graphite by Using Non-Ionic Polymer Surfactant

Graphene, a new material with 2-dimensional nanostructure consisting of a single layer of sp2 network of carbon atoms, has distinctive electronic properties such as room temperature quantum effects, arnbipolar electric field effects, and high carrier mobility. It is, however, difficult to fabricate graphene film from graphite via a solution process using organic solvent, though it is a cheap and convenient way compared to the CVD method. In this study, we report a new method to fabricate graphene film using a polymer surfactant to disperse homogeneously graphene sheets in ethanol. The surfactant consists of oligothiophene, which is strongly adsorbed onto the graphene surface, and polyethylene glycol, which interacts with ethanol. Hence, the surfactant is expected to effectively disperse graphene sheets in ethanol. Graphene film with a sheet resistance of 300 0/sq at 72% transmittance at 550 nrn was fabricated by vacuum filtration. When the film quality and thickness of graphene sheets are measured by Raman spectroscopy and transmission electron microscope, it reveals that our films have better quality as compared to graphene films reported previously.OAIID:oai:osos.snu.ac.kr:snu2012-01/104/0000001236/20SEQ:20PERF_CD:SNU2012-01EVAL_ITEM_CD:104USER_ID:0000001236ADJUST_YN:NEMP_ID:A004558DEPT_CD:445CITE_RATE:0FILENAME:2012추계학술대회_강민수.pdfDEPT_NM:재료공학부EMAIL:[email protected]:

원자계와 광학계에서의 거시 양자 상태 생성과 정량화

학위논문(박사)--서울대학교 대학원 :자연과학대학 물리·천문학부,2015. 2. 정현석.We discuss a classification of quantum effects based on possibility of emergence in macroscopic scales. We regard a certain phenomena as a genuine macroscopic quantum effect, if it cannot be described by any classical physics nor an accumulation of microscopic quantum effects. A quantum state corresponding to such effect is called a macroscopic quantum state. One prominent aspect among various quantum effects is quantum entanglement. We investigate possibilities of generating macroscopic entanglement between an atom and a thermal state or even between multiple thermal states. We found entanglement is always risen for an arbitrarily large temperature of the thermal states. This indicates importance of coherent interactions rather than the necessity of initial purities. We also propose a generation scheme for hybrid entanglement, which is comprised of classical and quantum states, based on single–photon addition technique. The key idea is that adding a single photon into a coherent state makes another approximate coherent state with a larger amplitude. Since it does not require in–line nonlinear interactions, it is experimentally feasible compared to traditional schemes. Besides generating entanglement, we also attempt to quantify the macroscopic quantumness for arbitrary quantum states of spins. We construct a measure of macroscopic quantumness by counting oscillations of interference fringes in phase space. We apply the measure to typical and intuitive macroscopic quantum states and verify that the measure works properly. Remarkably, we show that quantum phase transition is a naturally occurring genuine macroscopic quantum effect in the spirit of Schr¨odingers cat.Abstract I. Introduction II. Macroscopic Quantum Effects 2.1 Accumulation of microscopic quantum effects 2.2 Genuine macroscopic quantum effects III. Generating Entanglement from High Temperature Thermal States 3.1 Quantum entanglement 3.2 Thermal states 3.3 Entanglement of thermal states 3.3.1 Entangling microscopic system and thermal state 3.3.2 Entangling two thermal states 3.4 Macroscopic quantumness of entangled thermal states 3.5 Remarks IV. Generating Hybrid Entanglement via Photon Addition Scheme 31 4.1 Concept of hybrid entanglement 4.2 Amplifying coherent state by photon addition 4.2.1 Photon addition scheme iii4.2.2 Coherent state amplification 4.3 Generating hybrid entanglement 4.4 Macroscopic quantumness of hybrid entanglement 4.5 Remarks V. Quantifying Macroscopic Quantumness of Spin States 5.1 Introduction 5.2 Review of macroscopic quantumness for optical states 5.3 Macroscopic quantumness of spin states 5.3.1 Wigner distribution of spin states 5.3.2 Measure of macroscopic quantumness of spin states 5.3.3 Comparison to existing measures 5.4 Applications 5.5 Quantum phase transition 5.5.1 Quantum phase transition of Ising model 5.5.2 Macroscopic quantumness of quantum phase transition 5.6 Remarks VI. Conclusion Bibliography 국문초록Docto

천초근(Indian madder color)의 F344 랫드에서 104 주 경구투여에 의한 발암성 연구

학위논문 (박사)-- 서울대학교 대학원 : 수의학과 수의병리학전공, 2013. 2. 김대용.천초근(Indian madder color, IMC), 즉 Rubia cordifolia Linne의 뿌리는 식용 색소와 섬유의 염색, 그리고 전통약재로 사용되었다. 그러나, 다른 천초근(Madder color, MC)의 추출물의 연구에서 랫드 간세포와 신장 세뇨관 상피세포에 대한 발암성이 보고되었다. IMC와 MC, 두 종은 유사하므로 IMC 발암성의 가능성이 제기되었으므로 이에 대한 평가가 필요하게 되었다. 그러므로 IMC의 발암성평가를 위해서, F344 rat를 이용한 104 주 발암성 연구를 수행하였다. 40, 200 및 1,000 mg/kg의 투여용량으로 104주 동안 일주일에 다섯 번씩 IMC추출물을 경구 투여하였다. 생존 분석에서 수컷 1,000 mg/kg 투여 그룹에서 비록 빈사동물의 수는 유의성있게 증가되었으나(P<0.05), 폐사와 빈사를 합친 개체 수의 변화는 유의성이 없었다. 투여 77 주 이전에 체중과 사료섭취량은 일부 변화가 관찰되었으나(P<0.05) 용량상관성을 보이지는 않았다. 부검 시 관찰된 대퇴골, 두개골의 뼈에서 주로 관찰된 분홍색으로의 변색은 암수1,000 mg/kg 투여 그룹에서 유의성(P<0.01)있게 증가되었다. 간세포의 난원세포증식은 수컷 40, 200, 그리고 1,000 mg/kg 투여 그룹에서 증가하였다. 그리고 신장 유두부위 광물화(mineralization)는 수컷 1,000 mg/ kg 투여 그룹에서 증가하였으나 수질부의 광물질화(mineralization)는 암컷 1,000 mg/kg 투여 그룹 (P<0.01)에서 감소하였다. 대조군에 비해 암수의 1,000 mg/kg 투여 그룹에서 종양성(neoplastic) 병변은 큰 차이를 보여주지 않았다. 그러므로 본 연구은 104 주 동안 IMC의 투여에 의한 발암성이 없는 것으로 나타났다. 이러한 결과에서 IMC의 NOAEL은 1,000 mg/kg 이었다.Indian madder color (IMC), one of Radix Rubiae in herbal medicine, has been used for food coloring, and dye of textiles. However, madder color, another kind of Radix Rubiae, has been reported to have carcinogenicity in the liver and kidney of laboratory animals. So a carcinogenicity evaluation of IMC was needed because they are close-related species. For the risk assessment of IMC, 104-week carcinogenicity study was carried out. F344 rats were treated with hydrothermal extract of IMC for five times per week during 104 weeks by oral gavage at dose levels of 40, 200 and 1,000 mg/kg. In survival analysis, the number of overall unscheduled dead rats was not significantly changed, though the number of moribund rats in male 1,000 mg/kg dose group was significantly increased (P<0.05). The body weight and food consumption were changed significantly until 77 weeks (P<0.05), but the changes did not show dose-dependency. Macroscopically, cases with pink discoloration of bone, mainly in femur and skull was significantly increased in male and female 1,000 mg/kg dose groups (P<0.01). Microscopically, hepatic oval cell hyperplasia was significantly increased in male 40, 200 and 1,000 mg/kg dose groups. And renal papillary mineralization and pigmentation was significantly increased in male 1,000 mg/kg dose group (P<0.01). And no significant difference in neoplastic lesions was in male and female 1,000 mg/kg dose groups compared to control. These results do not show that IMC had a toxic effect at 1,000 mg/kg dose. From these results, oral treatment of IMC for 104 weeks in F344 rats had no carcinogenicity and the no-observed-adverse-effect level of IMC was 1,000 mg/kg dose.Abstract i Table of Contents ii Literature Review 1 Carcinogenicity study 1 Carcinogenicity study of herbal medicine 3 Indian madder color (IMC) 4 Chemical constituents of IMC 4 Pharmacological effect of IMC 6 Carcinogenicity study of Rubiae Radix 8 Chapter 1. A 104-week carcinogenicity study of Indian madder color by gavage in F344 rats 9 Introduction 10 Materials and Methods 12 Chemicals 12 Experimental animals 12 Study design overview 13 Administration 14 Clinical signs 14 Body weight 14 Food consumption 14 Ophthalmic examination 15 Hematology 15 Serum biochemistry 15 Necropsy findings and organ weights 16 Histopathology 16 Statistical methods 17 Results 19 Chemicals 19 Survival analysis 19 Body weight 20 Clinical sign and ophthalmological results 20 Hematological and serum biochemistry results 21 Organ weights 21 Necropsy findings 21 Cause of death 21 Histopathological findings 22 Discussion 24 Chapter 2. Histopathological analysis in the IMC carcinogenicity study 27 Introduction 28 Methods 30 Histopathology 30 Statistical methods 31 Results 32 Scheduled dead rats 32 Unscheduled dead rats 33 Scheduled and unscheduled rats 37 Discussion 39 Conclusions 45 References 46 국문초록 120 Figures and Tables Figure 1. Flower, leaves, stalk and root of Rubia cordifolia Linne (left) and dried roots (right). 50 Figure 2-1. LuP metabolism in the rats. 51 Figure 2-2. AlP metabolism in the rats. 52 Figure 3. Kaplan-Meier survival curves (male). Survival curve of 1,000mg/kg dose group (G4), were dropped rapidly but the survival rate are insignificant by log-rank test. 53 Figure 4. Kaplan-Meier survival curves (female). There is no dose-dependent change in the graph and have no statistical significance by log-rank test. 54 Figure 5. Body weight graph of males and females. Body weight of treatment groups increase similarly with control group. 55 Figure 6. Average food consumption of males. Food consumption in male has significant changes in the graph, but they are fluctuating. 56 Figure 7. Average food consumption of females. Graph show the food consumption per day in females and is fluctuating but they have similar pattern. 57 Figure 8. Organ distribution of LGL leukemia/lymphoma in males. In male incidence of LGL leukemia/lymphoma is high over 60% and all of them can be recognizable by spleen suggesting primary site. 58 Figure 9. Organ distribution of LGL in females. In females, incidences of LGL leukemia/lymphoma are also high in the spleen and liver. 59 Figure 11. Spleen, LGL leukemia/lymphoma. Neoplastic round cells are abundant in red pulp with prominent congestion. 60 Figure 12. Liver, LGL leukemia/lymphoma. Neoplastic round cells are infiltrating into the sinusoid and the hepatic parenchyma. The cells tend to be pleomorphic and large, with round to irregular-shaped nuclei and cytoplasmic granules. 61 Figure 13. Testes, interstitial cell adenoma. Tumors are composed of neoplastic cells compressing adjacent tubules, abundant finely vacuolated/granular eosinophilic cytoplasm. 62 Figure 14. Adrenal gland, pheochromocytoma. Note the large mass of proliferating cells which has cytology variable range from small, dark, lymphocyte-like cells to plump pale basophilic cells. 63 Figure 15. Pituitary gland, the pars distalis adenoma. Note the well delineated mass of cells that compresses the surrounding parenchyma. The neoplastic cells are arranged in compact branching cords with marked hemangiectasis. 64 Figure 16. Thyroid gland, follicular adenoma. Neoplastic cells are monomorphic and arranged in the prominent tubular structures at the margin of the mass. 65 Table 1. Alizarin, lucidin and rubiadin concentration using the water-based or ethanol-based extract methods (Kim et al., 2007) 66 Table 2. Guidelines of carcinogenicity and chronic study by regulatory agencies 67 Table 3. Survival table 68 Table 4. Summary of hematological test 69 Table 5. Summary of clinical biochemistry test 71 Table 6. Significant changes of absolute and relative testis weights (scheduled sacrificed rats, Absolute (g) & relative (%) organ weights) 73 Table 7. Necropsy findings with significant changing when compare dose groups to control group 74 Table 8. Cause of death summary in all examined rats 76 Table 9-1. Group percent of neoplasm incidences (scheduled dead rats) 77 Table 9-2. Group percent of neoplasm incidences (unscheduled dead rats) 78 Table 9-3. Group percent of neoplasm incidences (unscheduled dead rats, week 81-105) 79 Table 10-1. Incidences of all lesions of unscheduled dead rats (week 51-80) 80 Table 10-2. Incidences of all lesions of unscheduled dead rats (week 81-105) 81 Table 11. Incidences of histopathological lesions in the liver of scheduled dead rats 82 Table 12. Incidences of histopathologic lesions in the kidney of scheduled dead rats 83 Table 13. Statistically significant neoplasm in unscheduled female groups with Fishers exact test 84 Table 14. LGL leukemia/lymphoma in the all examined rats with poly-3 test 85 Table 15. Nonneoplastic lesion incidence in selected organs (all examined rats) 86 Table 16. Summary table of increased lesions from the results of poly-3 test. 87 Table 17. Pathological findings with grade in the adrenal gland 88 Table 18. Pathological findings with grade in the kidney 89 Table 19. Pathological findings with grade in the preputial gland 90 Table 20. Pathological findings with grade in the lung 91 Table 21. Pathological findings with grade in the sternum (bone marrow) 92 Table 22. Pathological findings with grade in the spleen 93 Table 23. Pathological findings with grade in the liver 94 Table 24. Incidences of neoplastic and other proliferative lesions in all examined rats (in life time) 97 Table 25. Histopathology summary in the scheduled dead rats 104Docto

우리나라 歷代 國務總理의 政治的 位相에 관한 硏究

학위논문(석사)--서울大學校 行政大學院 :行政學科 行政學專攻,1995.Maste

Bicameralism Debate during the Syngman Rhee Regime

학위논문(석사) -- 서울대학교대학원 : 인문대학 국사학과, 2023. 8. 이동원.This thesis examines the debate on the adoption and realization of bicameralism during the Syngman Rhee regime (the first Republic of Korea, 1948-1960). Previous studies have regarded this debate as trivial because a bicameral legislature was never realized before the collapse of the regime. Certain evidence, however, point to the opposite direction. The bicameralism argument continued for the entire duration of the regime, and involved major political entities, including Syngman Rhee himself. This thesis summarizes the development and key issues of the bicameralism debate, and thus sheds a light on the relevant political dynamics and conflict of interests during the first Republic of Korea. In 1948, the Constituent National Assembly rejected bicameralism. Although the reference draft had adopted it, the constitution drafting committee and assemblymen of plenary sessions rejected the idea. Rhee insisted on adopting bicameralism alongside the presidential system. This failed, however, because it presupposed an initially unicameral legislature, which figured as a threat to the legitimacy of the nascent Republic of Korea. After the establishment of ROK, Rhee again suggested a bicameral system to overpower the opposition, then the majority. The opposition threatened Rhees administration with a parliamentary cabinet system. Rhee proposed direct presidential election and bicameralism as a countermeasure. With the latter, Rhee aimed to offset pressure from the lower house and block the passage of constitutional amendments potentially weakening presidential power, such as one towards a parliamentary system. Rhee began pushing his plan for direct election and a bicameral system after the Korean War broke out. The majority of the Second National Assembly opposed, favoring a parliamentary cabinet system and single chamber. Rhee's first attempt of constitutional amendment was overwhelmingly voted down in January 1952. Subsequently, when parliamentary cabinet system advocates proposed a bill for constitutional amendment in April 1952, Rhee proposed his own bill and instigated the Pusan Political Crisis to press the Assembly. The purpose of the Pusan Political Crisis was to introduce a government-appointed upper house that would neutralize the Assembly, as well as to legislate direct presidential election. The upper house, one-third of which would be designated by the government, could fundamentally block attempts of the lower house to pass the parliamentary constitutional amendment and to override the presidential veto of bills. Rhee's idea was deleted from the compromise amendment, however, because this conflicted with the interests of assemblymen who were pro-Rhee but sought compromise. Rhee rejected this version of the compromise amendment and insisted on his original idea. The intervention of the UN and the United States stopped him, however, as he could not risk further aggravating the political crisis. The first constitutional amendment was made based on the compromise bill, and a bicameral system was adopted. Still, Rhee had failed to neutralize the Assembly via constitutional amendment. As an alternative, he tried to pass an election law on the House of Councillors (upper house), expected to bias election results to his side. Rhee's first draft of this election law as of October 1953 included several devices limiting candidates autonomy. This caused an overall resistance in the National Assembly regardless of party membership in November the same year. So the Assembly passed the election law only after neutralizing all the restrictive devices that Rhee proposed. Rhee vetoed this election law. Failing to adopt a bicameral system in his favor, Rhee proposed another constitutional amendment. The constitutional amendment bill that Rhee and the Liberal Party proposed in 1954 allowed the incumbent president to run indefinitely, and legislated the presidential succession of the vice president. As this second constitutional amendment granted Rhee greater authority and a lifetime presidency, he did not pursue bicameralism with as much vigor as before. Rhee again proposed a bill for the establishment of an upper house in 1955, but it was not seriously taken up by either Rhee or the assemblymen of both parties. Bicameralism resurfaced after the presidential election in 1956, when Liberals faced public resentment and Democrats achieved victory on vice-presidency. The Liberal Party attempted to nullify bicameralism, and proposed a parliamentary amendment in order to prevent the Democrat vice president from succeeding the regime. In reaction, Democrats argued for its reinstatement, accusing Liberals of 'unconstitutional' nullification of bicameralism. Rhee also made use of bicameralism to reject Liberals' amendment and to press them. Liberals ended up dropping the parliamentary amendment. The Liberal Party then concentrated on election law revision. Through negotiation, Liberals and Democrats enacted an election law for both the lower and upper houses. But after their defeat in the general election of 1958, Liberals claimed the futility of bicameralism, and Rhee also abandoned his support for it. Democrats, on the other hand, urged the organization of an upper house, convinced of their victory in the upper house election. A massive dispute broke out in the second half of 1958. Liberals put a violent end to this debate when they caused another political crisis on December 24th, neutralizing the enforcement deadline of the election law of the upper house. No further debate on bicameralism ensued in any degree of seriousness, and a bicameral system was not realized in ROK until the April Revolution of 1960 leading to the collapse of the Syngman Rhee regime.본 연구에서는 이승만 정권기(1948-1960) 양원제 논의의 전개 과정과 그 성격을 고찰하였다. 양원제는 1952년 제1차 개헌을 통해 도입되었으나 제1공화국기에 실현되지 않았으며, 따라서 기존 연구에서 거의 주목받지 못했다. 그러나 양원제 채택 및 실현 논의는 제1공화국 거의 전 시기에 걸쳐 진행되었으며, 이승만을 포함한 제반 정치세력들이 양원제를 두고 각축을 벌였다. 본 연구에서는 양원제 논의의 전 과정과 주요 쟁점을 정리하고, 이를 통해 제1공화국기 주요 정치세력의 이해관계 충돌 및 대립 양상을 조명했다. 1948년 제헌헌법 논의 당시 양원제는 채택되지 못했다. 참고자료로 활용된 헌법안에서는 양원제를 채택했지만, 헌법기초위와 국회 본회의 논의에서 양원제는 거부당했다. 이승만은 자신의 구상인 대통령중심제·양원제를 관철하려 했으나, 단원제 국회로 정부를 먼저 수립할 것을 전제로 한 그의 양원제 구상은 신생 정부의 안정성과 국제적 승인 가능성에 악영향을 줄 수 있었기에 수용되지 않았다. 정부수립 이후 여소야대의 상황이 조성되고 일각에서 내각책임제 개헌이 논의되자 이승만은 이에 대응해 양원제 도입론을 다시 제기했다. 특히 1950년 초 한민당-민국당이 야당을 자임하며 내각책임제 개헌을 제출하자, 이승만은 이를 반대하면서 대통령직선제·양원제 개헌을 자신의 정치적 목표로 내세웠다. 이승만은 양원제 도입을 통해 하원의 견제를 무력화하고 내각책임제 개헌 시도를 차단함으로써 자신의 권력을 강화하고자 했다. 이승만은 직선제·양원제 개헌을 전쟁 발발 이후 임시수도에서 본격적으로 추진했다. 개헌안 관철을 위해 이승만은 원내 여당을 만들려 했으나 실패했다. 원내 정치세력 다수는 오히려 내각책임제와 단원제를 선호했다. 직선제·양원제 구상과 내각책임제·단원제 구상이 충돌하는 상황에서 이승만은 첫 번째 개헌안을 제출했고, 이는 압도적으로 부결되었다. 내각책임제 개헌 지지 세력이 1952년 4월에 내각책임제 개헌안을 제출하자 이승만은 5월에 다시 개헌안을 제출했고, 정치파동을 일으켜 국회를 무력으로 압박했다. 이승만은 정치파동을 통해 대통령 직선제뿐 아니라 입법부를 무력화하는 양원제를 도입하고자 했다. 상원의 1/3을 이승만이 임명하여 하원의 활동을 제약하고, 주요 의결을 원천적으로 차단하도록 했다. 이승만의 구상은 그를 지지하면서도 타협을 모색하는 의원들의 이해관계와 충돌했다. 따라서 타협 의원들은 관선의원 규정을 삭제했다. 이승만은 관선제를 포함한 원안을 관철하고자 했으나, 미국과 유엔이 본격적으로 개입한 상황에서 정치파동 상황을 더 이상 악화시킬 수 없었기에 타협안을 받아들였다. 제1차 헌법 개정은 발췌 타협안을 바탕으로 이루어졌으며, 직선제와 양원제가 헌법에 도입되었다. 이승만은 직선제 개헌과 대통령 재선에 성공했지만, 국회를 무력화한다는 목표는 달성하지 못했다. 이승만은 차선책으로 선거의 변수를 줄이는 선거법 제정을 추진했다. 정부가 작성하여 제출한 참의원선거법에는 이승만이 의도한 각종 제한 규정이 포함되었다. 1953년 11월의 선거법 논의에서 원내 정치세력은 여야를 가리지 않고 자신들의 이해관계와 충돌하는 제한 규정을 대부분 삭제하거나 무력화시켰다. 이승만은 자신의 의도와 많이 달라진 선거법을 공포하지 않고 거부하여 폐기했다. 자신에게 유리한 양원제 도입에 실패한 이승만은 권력 강화를 위해 새로운 개헌을 추진했다. 1954년 이승만과 자유당은 자신에 대한 중임 제한 철폐와 국무총리제 삭제, 부통령 계승권 법제화 등을 골자로 한 개헌안을 제출했다. 제2차 개헌을 통해 이승만은 대통령제 강화와 종신 집권이라는 목표를 달성했기에, 이전처럼 양원제에 대한 강한 의지를 보이지 않았다. 1955년 이승만은 다시 참의원선거법을 제출했으나, 이승만뿐 아니라 여야 의원들 또한 참의원 구성에 적극적이지 않았기에 선거법은 제대로 논의되지 않았다. 1956년 대통령 선거에서 이승만의 득표 비율이 줄어들고 부통령 선거에서 이기붕이 패배하면서, 참의원 구성 문제는 이승만과 여당, 야당의 이해관계가 엇갈리는 쟁점이 되었다. 자유당은 이전의 소극적인 정도를 넘어서 아예 양원제 구상 자체를 백지화하려 했다. 나아가 정국을 전환하고 야당의 권력 승계를 막기 위해 내각책임제 개헌을 추진했다. 민주당은 자유당의 개헌 시도를 비판하면서 현행 헌법의 준수, 즉 참의원의 조속 구성을 주장했다. 이승만 또한 자유당의 내각책임제 개헌을 수용하지 않았으며, 자유당 압박을 위해 참의원 구성 문제를 활용했다. 결국 자유당은 개헌을 포기했다. 자유당은 또 다른 당면 문제인 선거법 개정에 집중했고, 야당과의 합의를 통해 민의원·참의원 선거법을 제정했다. 그러나 자유당은 여전히 참의원을 구성할 생각이 없었다. 1958년 민의원선거에서 실질적으로 패배한 후 자유당은 본격적으로 양원제 회의론을 주장했으며, 이승만 또한 양원제 실현을 포기했다. 반대로 민주당은 참의원 선거에서도 약진할 것을 확신하고 현행법에 따른 참의원 조속 구성을 주장했다. 1958년 하반기 민주당은 양원제 실현을 당론으로 내세우고 강력한 대정부·여당 공세를 취했다. 여야가 첨예하게 충돌한 양원제 문제는 결국 자유당이 또 다른 정치파동을 통해 참의원 선거 법정 기일을 무력화하는 파국적인 방식으로 종결되었다. 이후 4월혁명 직전의 개편 시도를 제외하면 참의원 구성 문제는 더 이상 진지하게 논의되지 못했으며, 결국 이승만 정권이 무너지기까지 양원제는 실현되지 못했다.머 리 말 1 一. 단원제 국회 구성과 이승만의 양원제 개헌론 8 1. 제헌헌법 논의와 대통령중심제-단원제 채택 8 2. 이승만의 양원제 개헌론 제기와 국회와의 갈등 15 二. 양원제 채택과 이승만 구상의 굴절 27 1. 발췌개헌 논의와 직선제-양원제 채택 27 2. 참의원선거법 제정 시도와 무산 42 三. 국회 주도의 양원제 논의와 양원제 실현의 좌절 50 1. 여당의 개헌 제기와 야당의 양원제 논의 활용 50 2. 참의원선거법 제정과 여야의 입장 전환 65 맺 음 말 81 참고문헌 86 Abstract 91석

Theoretical study on dielectric slab optical interconnects between distanced plasmonic waveguides

학위논문(석사) --서울대학교 대학원 :전기. 컴퓨터공학부,2010.2.Maste

상완 근지구력 검사의 준거지향기준 설정에 관한 연구

학위논문(석사)--서울대학교 대학원 :체육교육과,1997.Maste

어머니와 자녀의 정서지능 관계연구

학위논문(석사)--서울대학교 대학원 :교육학과 교육학전공,2001.Maste