중국 인민해방군 항공기의 한국방공식별구역 및 일본방공식별구역 진입양상 및 요인 비교분석

학위논문(석사) -- 서울대학교대학원 : 국제대학원 국제학과(국제협력전공), 2024. 2. Sheen, Seong-Ho.This thesis focuses on analyzing the flight patterns of the Peoples Liberation Army (PLA) within the Republic of Korea and Japan's Air Defense Identification Zones (ADIZs) from the early 2010s, aiming to compare and explain the differences between these two patterns. Furthermore, it seeks to identify the factors leading to such differences. ADIZ possesses a degree of legal ambiguity. In such circumstances, the heightened maritime interests of each state have transformed these zones into proactive means that support not just only airspace defense but also the economic and military security interests of each state. With China's rise, the changes in air defense identification zones (ADIZ) in East Asia and the accompanying military aircraft operations are becoming factors that contribute to more intricate and acute conflicts within East Asia, entangled with historical and territorial issues. The thesis attempts to categorize the entry patterns of Chinese PLA aircraft into the Republic of Korea and Japan's ADIZs based on the dual axis of bilateral relations and core interests. The aircraft's entry patterns into these zones manifest distinct behaviors during escalated tension and relative reconciliation between the states. In the case of KADIZ, PLA aircraft operation occurred around high-level talks before and after a deterioration in relations due to the THAAD issue. During periods of relationship improvement or reconciliation, flights within the KADIZ seemed to occur due to the PLAs planned training and operations. Conversely, PLA aircraft in JADIZ demonstrates flights utilizing increased frequency during times of strained relations, leveraging numerical superiority due to issues regarding the Senkaku/Diaoyu and Guidance for U.S.-Japan Defense Cooperations. Even following relative relationship improvements, PLA maintains flight into JADIZ with sustained frequencies, unlike reductions observed in KADIZ case. This paper argues that these distinctions stem from core interests. Ultimately, JADIZ encompasses more elements of core interests than KADIZ, leading to overwhelming air operations employing fait accompli strategies and salami tactics. Through this research, it asserts that one crucial aspect of China's military actions revolves around the determination of core interests. Furthermore, based on this premise, it is possible to speculate about the tactics China might employ to safeguard these core interests.이 논문은 2010 년대 초반 이후 중국 인민해방군 항공기의 한국방공식별구역(KADIZ) 및 일본방공식별구역(JADIZ) 내 비행 양상을 분석하고 두 양상의 차이점을 비교 설명하는데 초점을 둔다. 더 나아가 그러한 차이점이 발생하게 된 요인을 찾는다. 방공식별구역은 법적 지위의 모호성을 가지고 있다. 이러한 상황에서 더욱 커진 각 국가의 해양 권익은 방공식별구역으로 하여금 영공 방어를 넘어 국가의 경제적, 군사안보적 이익을 뒷받침해주는 적극적 수단으로 자리잡게 하였다. 오랫동안 과거사와 영토 문제로 얽혀 있었던 동아시아 내에서 중국의 부상과 함께 발생한 방공식별구역의 변화들과 이에 수반되는 항공 작전들은 더욱 복잡하고 첨예한 대립을 만들어 낼 수 있는 요소이다. 논문을 통해 중국 인민해방군 항공기의 한국방공식별구역 및 일본방공식별구역 진입 양상을 양자 관계와 핵심 이익이라는 두 축을 기준으로 구분하려고 시도한다. 인민해방군 항공기의 방공식별구역 진입 양상은 양국관계가 악화시기일때와 상대적 회복시기일때 각각 다른 모습으로 나타난다. 한국 방공식별구역 사례의 경우 THAAD 문제로 인한 관계 악화 시 양국의 고위급 회담, 또는 정상회담을 전후로 정치적 의도와 성격을 띈 인민해방군 항공기의 작전이 진행되었다. 상대적 관계 회복 시에는 중국 인민해방군의 계획된 훈련 및 작전을 바탕으로 한국 방공식별구역 내 비행이 진행된 것처럼 보인다. 반면 일본 방공식별구역 사례의 경우 중국 인민해방군은 센카쿠열도 문제 및 신(新) 미일 방위 협력지침 등으로 인한 관계 악화 시 수적 우세를 이용하여 비행 빈도를 증가시키는 방식의 비행양상을 보여준다. 또한 상대적 관계 개선 이후에도 비행 빈도를 크게 감소시키지 않고 유지하는 형태의 모습을 보인다. 이 논문을 통해 위와 같은 이유가 핵심이익 때문임을 주장한다. 결론적으로 일본방공식별구역은 핵심 이익의 요소를 한국방공식별구역 보다 더 많이 포함하고 있으며 이 때문에 기정사실화(Fait accompli) 전략과 살라미(Salami)전술을 이용한 적극적인 비행 활동이 이루어짐을 볼 수 있다. 논문을 통해 중국의 군사적 행위의 중요한 요소 중 하나가 핵심 이익의 여부임을 증명한다. 또한 이를 토대로 중국이 핵심 이익을 수호하기 위해 어떠한 전술을 구사하는지 추측해 볼 수 있다.Chapter Ⅰ. Introduction 1 Chapter Ⅱ. Background Knowledge 6 1. Definition and Origin of ADIZ 6 2. Lawful status of ADIZ 8 3. ADIZ in Contemporary Japan, China, and Korea 11 4. PLA aircraft Entering neighboring ADIZ 14 Chapter Ⅲ. Literature Review 17 Chapter Ⅳ. Methodology and Theoretical Framework 22 1. Methodology 22 A. Collecting Data 22 B. Assembling Data 27 2. Framework for analysis 29 A. Major events amidst Bilateral Relationship 30 B. Core Interest 32 Chapter Ⅴ. Patterns of PLA Air Operation in KADIZ and JADIZ 33 1. Total Number of PLA Aircraft entering KADIZ/JADIZ 33 2. "Unusual Flights" with details reported through the press and its implication 36 A. Number of times PLA aircraft entering KADIZ/JADIZ in detailed data (By year, month, and day) 38 B. Types of PLA aircraft entering KADIZ/JADIZ in detailed data 45 C. Routes of PLA aircraft entering KADIZ/JADIZ in detailed data 52 3. Summary and Questions 58 A. Summary 58 B. Questions 58 Chapter Ⅵ. Bilateral Relationship and PLA Aircraft Operations 61 1. Korea-China Bilateral Relationship in 2013-2022 61 2. Correlation Between Bilateral Relations and Operations of PLA Aircraft in KADIZ 73 3. Japan-China Bilateral Relationship in 2010-2020 81 4. Correlation Between Bilateral Relations and Operations of PLA Aircraft in JADIZ 91 Chapter Ⅶ. Chinas Core Interest 97 1. Remain Questions 98 2. Chinas Core Interest 99 3. Analysis 111 Chapter Ⅷ. Conclusion 117 Bibliography 120 Abstract in Korean 134 Acknowledgements 136석

수직 낸드 플래시 시냅스 배열을 이용한 정확하고 효율적인 스파이킹 뉴럴 네크워크

학위논문(박사) -- 서울대학교대학원 : 공과대학 전기·정보공학부, 2024. 2. 김재준.인공 신경망은 비선형 계산 능력을 이용하여 컴퓨터 비전, 음성 인식 및 자연어 처리와 같은 다양한 분야에서 상당한 성능을 보여주고 있다. 최근 몇 년간의 인공 신경망 규모는 1000억개 이상의 시냅틱 매개변수를 이용할 정도로 거대해졌으나, 기존의 폰 노이만 구조는 시냅스 가중치 데이터의 저장 및 순차적인 이동으로 인해 최신 인공 신경망을 구현하는데 제약이 있다. 이러한 병렬성의 부재는 시냅틱 매개변수의 수가 증가하면서 중대한 문제가 된다. 이러한 기억장치 병목 현상을 극복하기 위해 메모리 내에서 연산을 수행하는 인메모리 컴퓨팅이 대두되고 있으며, 이는 메모리 내에서 직접 병렬 계산을 수행하여 메모리 간 혹은 연산장치 간의 데이터 이동량을 최소화한다. 특히 인메모리 컴퓨팅을 이용한 스파이킹 뉴럴 네트워크는 단일 스파이크 입력으로 아날로그 곱-누적 연산을 수행하여 낮은 전력 소비를 가지며, 생물학적 호환성이 높아 다음 세대의 인메모리 컴퓨팅이 될 수 있다. 스파이킹 뉴럴 네트워크는 시냅스로서 전하 트랩 플래시, 멤리스터를 비롯한 다양한 비휘발성 메모리 장치를 활용할 수 있으며, 이 중 전하 트랩 플래시는 다단계 가중치를 안정적으로 구현하며 삼단자 특성에 의한 높은 설계 유연성을 제공한다. 인공 신경망의 가중치를 고집적으로 저장하기 위해서는 셀 면적이 최소화된 수직 적층 낸드 플래시가 가장 적합한 선택지이다. 그러나 수직 적층 낸드 플래시는 읽기 동작 중에 여러 워드 라인을 선택할 수 없어서 이를 스파이크 신경망 방식으로 활용하기 위해서는 혁신적인 방법론이 필요하다. 본 논문에서는 수직 적층 낸드 플래시 기반의 스파이킹 뉴럴 네트워크를 구현하기 위한 새로운 가중치 매핑과 동작 방법을 제안한다. 제안된 스파이킹 뉴럴 네트워크는 기존의 상업용 수직 적층 낸드 플래시를 활용한다. 이는 노어 배열 또는 크로스바 배열과 유사하게 모든 네트워크 층에서 동시 신호 처리를 가능하게 하여 낸드 구조에서 비다중 워드 라인 선택에 의한 제약을 효과적으로 해결한다. 스파이킹 신경망의 기본적인 곱-누적 동작은 제작된 평면 낸드 플래시 배열을 이용하여 검증되었다. 추가적으로, 스파이킹 뉴럴 네트워크의 효율 및 정확도를 높이기 위한 추가적인 방법론들이 소개된다. 스파이킹 뉴럴 네트워크의 인메모리 컴퓨팅 동작은 다른 인메모리 컴퓨팅 동작과 다르며 시간순 입력에 의해 계산 처리량을 높이는 다양한 기술을 활용할 수 없는 문제가 있다. 본 논문은 가중치 공유 접근방식을 활용하여 이 문제를 해결하고 에너지 및 면적 효율적인 수직 적층 낸드 플래시 기반 스파이킹 뉴럴 네트워크를 가능하게 하였다. 마지막으로, 스파이킹 뉴럴 네트워크는 시냅스 배열의 저항-커패시터 성분에 의한 순시 전류발생 문제가 있으며, 본 논문에서는 국부 동기화 방법을 통해 이를 해결하여 정확한 스파이킹 방식의 인메모리 컴퓨팅이 가능하도록 한다. 제안하는 기술들에 의한 수직 적층 낸드 플래시 스파이킹 인메모리 컴퓨팅의 성능 향상은 파이썬 시스템 시뮬레이션으로 검증 되었다. 제안한 가중치 매핑 방법은 수직 적층 낸드 플래시를 이용하여 동시다발적인 처리를 가능하게 하였으며, 기존의 메모리들 중 최대 셀 밀도를 갖는 수직 적층 메모리를 이용하여 효율적이고 안정적인 대규모 인공 신경망을 구현할 수 있는 가능성을 보여준다.Artificial Neural Networks (ANNs) have exhibited remarkable performance in diverse domains such as computer vision, speech recognition, and natural language processing, thanks to their capacity for non-linear computations. In recent years, the scale of ANNs has grown exponentially with over one hundred billion synaptic parameters. However, the conventional von Neumann architecture faces limitations in implementing modern ANNs due to the sequential movement of synaptic weights between storage and computation units. This lack of parallelism becomes a significant issue as the number of synaptic parameters increases. To overcome this memory bottleneck, the neuromorphic system with a compute-in-memory (CiM) approach is emerging. CiM performs parallel computation directly within the memory, thereby minimizing the data transfer between different storages or computation units. In particular, the spiking neural network (SNN) using the CiM approach has the potential to become the next-generation CiM owing to its low power consumption and biologically plausible nature, achieved by performing analog multiply-accumulate (MAC) operations using a single bias input. The SNN can utilize various non-volatile memory devices such as charge trap flash (CTF) and memristors as a synapse. Among these, CTF allows stable implementation of multi-level weights and offers high design flexibility due to its three-terminal nature. To densely store the massive weights of ANNs, the vertically stacked (3-D) NAND-type flash array is the most suitable option with its minimized (<4F2) cell area. However, 3-D NAND flash cannot select multiple word lines (WLs) during read operations, requiring the need for a novel methodology to leverage it for SNNs. In this dissertation, a novel weight mapping method and operation method for accelerating SNN using 3-D NAND flash are proposed. The proposed SNN utilizes the existing commercial 3-D NAND flash array. Additionally, it enables simultaneous signal processing across all network layers akin to NOR-type or two-dimensional (2-D) crossbar arrays, thereby effectively addressing the constraint of non-multiple WL selection in NAND structures. The basic MAC operation for SNNs is validated using the fabricated planar NAND array. Furthermore, various methodologies are introduced to enhance the accuracy and efficiency of the SNN. The SNN-type CiM operation differs from other CiMs because of the time-series input, which prevents the utilization of various techniques to enhance computational throughput. In this dissertation, this issue is resolved by employing a weight-sharing approach, enabling the realization of an energy and area-efficient 3-D NAND flash-based SNN accelerator. Lastly, SNN has the issue of current overshooting caused by the resistive and capacitive components of the synaptic array during the spike input. In this dissertation, this issue is resolved by implementing a local synchronous approach, thereby improving the inference accuracy of the SNN inference. The performance enhancements of 3-D NAND flash-based SNN achieved by the proposed techniques are verified with Python-based system-level simulation. The proposed weight mapping method on 3-D NAND flash memory enables simultaneous processing utilizing 3-D NAND flash. The potential of efficient and stable large-scale ANN implementation is demonstrated by leveraging the highest cell density offered by 3-D NAND flash among existing memory devices.Abstract i Contents iv List of Tables vii List of Figures viii Chapter 1 Introduction 1 1.1 Compute-in-Memory 1 1.2 Spiking Neural Networks 7 1.3 Candidates for High Bit-Density Synapse 11 1.4 Outline of the Dissertation 15 Chapter 2 Simultaneous Processing of 3-D NAND Flash Synapses 16 2.1 Limitations of Multi-WL NAND Read Operation 16 2.2 Layer-to-BL Mapping in 3-D NAND Flash Synapses 22 2.3 Synaptic Array Operation for Simultaneous Processing 28 2.4 SPB Validation using Planar NAND Array 35 2.4.1 NAND Array Fabrication 35 2.4.2 NAND Array Measurement 36 2.4.3 SNN System-Level Simulation 38 2.5 Confirming Compatibility with 3-D NAND Flash 46 Chapter 3 Enhancement Methods of SNNs 49 3.1 Limitations for Efficient and Accurate SNNs 49 3.2 Multi-Input Processing SNN 52 3.2.1 Processing Flow of MSS 52 3.2.2 MSS Validation 54 3.3 Efficient Convolutional Processing of SNN 61 3.3.1 Processing Flow of ECL 61 3.3.2 ECL Validation 63 3.4 Accurate and Stable SNN inference 70 3.4.1 Operation of LS-SNN 70 3.4.2 LS-SNN Validation 72 3.5 Integration of Proposed Methods to 3-D NAND Flash Based SNN 76 3.5.1 Integration of MSS and ECL 76 3.5.2 Integration of LS-SNN 78 Chapter 4 System-Level Simulation 82 4.1 3-D NAND Flash Measurement 82 4.1.1 Measurement Setup and Basic Cell Characteristics 82 4.1.2 Cell Reliability Characteristics 86 4.1.3 Cell Area Estimation 87 4.2 Evaluation Setup 90 4.3 Simulation and Evaluation Results 93 4.3.1 Accuracy and Latency 93 4.3.2 Quantitative Comparison of Efficiency 94 4.3.3 Result Summary 100 Chapter 5 Conclusion 109 Bibliography 112 초록 124박

Concomitant Right Ventricular Outflow Tract Cryoablation during Pulmonary Valve Replacement in a Patient with Tetralogy of Fallot

A 38-year-old female patient with a history of tetralogy of Fallot repair at 10 years of age underwent pulmonary valve replacement with a mechanical prosthesis, tricuspid annuloplasty, and right ventricular outflow tract cryoablation due to pulmonary regurgitation, tricuspid regurgitation, and multiple premature ventricular contractions with sustained ventricular tachycardia. After surgery, she had an uneventful postoperative course with arrhythmia monitoring. She was discharged without incident, and a follow-up Holter examination showed a decrease in the number of ventricular ectopic beats from 702 to 41.ope

Results of Extracorporeal Cardiopulmonary Resuscitation in Children

Background : Survival of children experiencing cardiac arrest refractory to conventional cardiopulmonary resuscitation (CPR) is very poor. We sought to examine current era outcomes of extracorporeal CPR (ECPR) support for refractory arrest. Methods : Patients who were <18 years and underwent ECPR between November 2013 and January 2016 were including in this study. We retrospectively investigated patient medical records. Results : Twelve children, median age 6.6 months (range, 1 day to 11.7 years), required ECPR. patients’ diseases spanned several categories: congenital heart disease (n=5), myocarditis (n=2), respiratory failure (n=2), septic shock (n=1), trauma (n=1), and post-cardiotomy arrest (n=1). Cannulation sites included the neck (n=8), chest (n=3), and neck to chest conversion (n=1). Median duration of extracorporeal membrane oxygenation was five days (range, 0 to 14 days). Extracorporeal membrane oxygenation was successfully discontinued in 10 (83.3%) patients. Nine patients (75%) survived more than seven days after support discontinuation and four patients (33.3%) survived and were discharged. Causes of death included ischemic brain injury (n=4), sepsis (n=3), and gastrointestinal bleeding (n=1). Conclusion : ECPR plays a valuable role in children experiencing refractory cardiac arrest. The weaning rate is acceptable; however, survival is related to other organ dysfunction and the severity of ischemic brain injury. ECPR prior to the emergence of end-organ injury and prevention of neurologic injury might enhance survival.ope

Usefulness of 3-Dimensional Body Surface Scanning in the Evaluation of Patients with Pectus Carinatum

Background: Radiographic modalities have been commonly used to evaluate pectus carinatum (PC), and compressive orthotic bracing is the most widely accepted treatment method. The aim of this study was to determine the efficacy of 3-dimensional (3D) body surface scanning as an alternative modality for the evaluation of PC. Methods: The medical records of 63 patients with PC who were treated with compressive orthotic bracing therapy between July 2017 and February 2019 were retrospectively analyzed. Using both 2-view chest radiography (posteroanterior and lateral view) and 3D body scanning, the height of maximal protrusion of the chest wall was measured both before and after 2 weeks of bracing therapy. The difference between the pre- and post-treatment measurements was calculated for both modalities, and these differences were compared and analyzed. Results: Based on the comparison between the pre- and post-treatment radiographs, bracing therapy produced favorable outcomes in all patients (p<0.001). The measurements obtained via 3D scanning were strongly correlated with those obtained via chest radiography (r=0.60). Conclusion: Based on the findings of this study, 3D body surface scanning appears to be an effective, radiation-free, and simple method for the post-treatment follow-up evaluation of PC, and thus can be considered an alternative to radiography.ope

Adult Kidney Transplantation of Pediatric En bloc Kidneys Using a Partial Bladder Wall

Kidney transplantation is a treatment of choice which improves survival and quality of life for patients with end-stage renal disease. Due to the growing waiting list for kidney transplantation, expansion of the donor pool to use of deceased pediatric kidneys is of critical importance. However, the use of pediatric kidneys has been limited due to concerns about early graft failure, hyperfiltration injury, and technical difficulties. Performing ureteroneocystostomy using small pediatric en bloc kidneys is sometimes difficult due to the small diameter and short length of the ureter in the adult kidney recipient. We hereby report on a partial bladder wall transplantation using pediatric en bloc kidneys. Pediatric en bloc kidneys and partial bladder wall from a 12-month-old female donor who weighed 9.13 kg was transplanted into a 49-year-old male recipient. The urinary tract was reconstructed with a partial bladder wall of the donor. At 12 months post-transplantation, Doppler ultrasonograpy and renogram showed stable graft renal function without urological complications. Pediatric en bloc kidney transplantation with a partial bladder wall can be a safe and feasible surgical technique to reduce urological complications.ope

Intracardiac Thrombosis Involving All Four Cardiac Chambers after Extracardiac Membranous Oxygenation Associated with MTHFR Mutations

A 4-month-old boy diagnosed with acute myocarditis was treated with extracorporeal membrane oxygenation (ECMO). Follow-up echocardiography eight hours after ECMO revealed intracardiac thrombosis involving all four heart chambers. Because of the high risk of systemic embolization due to a pedunculated thrombus of the aortic valve, we performed an emergency thrombectomy. After the operation, the patient had a minor neurologic sequela of left upper arm hypertonia, which had almost disappeared at the last outpatient clinic two months later. He was diagnosed with a major mutation in MTHFR (methylenetetrahydrofolate reductase), which is related to thrombosis.ope

Two Cases of Antibody-Mediated Rejection Following Kidney Transplantation due to HLA-DQB1 Allele-Specific and DQ Alpha Protein-Specific HLA Antibodies

ope

Sirolimus Combination with Tacrolimus in Kidney Transplant Recipients at High Immunological Risk: Observational Results 3 Years after Transplantation

Background : The optimal immunosuppressive strategy for renal transplant recipients at high immunological risk requires clarification. We compared the 3 year outcomes of a sirolimus group (tacrolimus plus sirolimus) to those of a control group (tacrolimus plus mycophenolate mofetil). Methods : This observational study was an extension of a prospective pilot study. We assessed acute rejection, glomerular filtration rate, adverse events, graft, and patient survival. Results : Overall, 43% of the sirolimus group versus 78% of the control group were still on the initial immunosuppressive regimen at 3 years (P=0.005), and most discontinuations in each group were due to adverse events. No differences were observed between two groups with respect to acute rejection. The mean glomerular filtration rate at 36 months was greater in the sirolimus group than in the control group, but this was not statistically significant (64.0±6.8 mL/min/1.73 m2 vs. 61.8±17.1 mL/min/1.73 m2,P=0.576). Graft and patient survival were similar in both groups. Importantly, mean tacrolimus through levels were significantly lower in the sirolimus group than in the control group at each time point. No neoplasm was reported in the sirolimus group. In the control group, three cases of neoplasms developed during the study period. Conclusions : The sirolimus group had a greater number of discontinuations, particularly related to adverse events. Nevertheless, optimal concentration of sirolimus allowed reduced calcineurin inhibitor exposure in high immunologic risk patients, without increasing the risk of acute rejection and graft failure.ope

The role of postoperative radiotherapy in stage II and III thymoma: a Korean multicenter database study

Background: Complete resection is a standard treatment for patients with Masaoka-Koga stages II and III thymoma, however the role of postoperative radiotherapy (PORT) is controversial. We analyzed data collected from 4 Korean hospitals to determine the effectiveness of PORT in stage II and III thymoma patients. Methods: Between January 2000 and December 2013, 1,663 patients underwent surgery for thymic tumors at the 4 hospitals. Among them, 668 patients (527 with stage II and 141 with stage III) were investigated, among whom, 443 received PORT (335 with stage II and 108 with stage III). Propensity score matching (PSM) was performed, and 404 patients (346 with stage II and 58 with stage III) were selected. Results: Perioperative characteristics were similar in the PORT and non-PORT groups after PSM. On survival analysis of stage II patients, the PORT and non-PORT groups showed no difference in either 5-year recurrence-free survival (RFS) (96.3% vs. 96.6%, P=0.622) or 5-year overall survival (OS) (94.6% vs. 93.8%, P=0.839). However, among stage III patients, the PORT group showed significantly better 5-year RFS (75.7% vs. 50.1%, P=0.040) and 5-year OS (86.5% vs. 54.7%, P=0.001). On multivariate Cox regression analysis, PORT was a significant positive prognostic factor in terms of both RFS (P=0.005) and OS (P=0.004) in patients with stage III thymomas, but not in those with stage II disease (P=0.987 and 0.968, respectively). Conclusions: PORT improved the RFS and OS in stage III thymoma patients, but showed no survival benefit in stage II patients.ope