사회 인지와 상식을 갖춘 대화형 인공지능을 위한 연구

학위논문(박사) -- 서울대학교대학원 : 공과대학 컴퓨터공학부, 2023. 8. 김건희.As conversational agents become increasingly popular for their ability to provide abundant factual knowledge, it is important that those agents also possess the capability to process rich social information. In this dissertation, we work towards improving conversational agents' social cognition and their awareness of various social commonsense. In the first part, we introduce methods for improving the response generation of machine agents by drawing inspiration from social cognition and pragmatics. We propose novel decoding methods based on the Rational Speech Acts framework, which enable existing conversational agents to become more consistent and focused on the interlocutor's utterances. In the second part, we demonstrate how to construct conversation datasets infused with social commonsense knowledge. In particular, we examine the positivity bias in existing dialogue datasets and introduce ProsocialDialog to counterbalance it and make conversational agents more prosocial against problematic user inputs. Additionally, we present SODA to significantly improve the quality and scale of existing dialogue datasets using a large language model and a commonsense knowledge graph. We conclude this thesis by discussing the contributions and promising future directions towards improving the social competence of conversational agents.최근 대화형 인공지능이 사용자에게 보다 넓은 범위의 사실적 지식을 적확하게 전 달할 수 있게 되면서 그 사용처가 확대되고 있다. 이에 따라, 다양한 사회적 상호 작용에서 발생하는 정보를 처리하는 능력을 갖추는 것 또한 중요해지고 있다. 본 학위 논문에서는 대화형 인공지능으로 하여금 더 나은 사회 인지 기제와 다 양한 사회적 상식을 갖추도록 하는 여러가지 방법들을 소개한다. 본론 1부에서 는 사회 인지와 화용론에서 착안하여 대화 인공지능의 답변 생성 결과를 개선하 는 기법들을 제안한다. 구체적으로, 제 3 장에서는 대화 인공지능의 생성된 답변 이 보다 자신의 페르소나에 일관될 수 있도록 Rational Speech Acts 프레임웍에 기 반한 새로운 디코딩 방법을 소개한다. 제 4 장에서는 대화에서 상대방의 감정의 원 인과 관련된 단어를 약지도학습(weakly supervised learning)으로 파악하는 기법 을 제안한다. 그리고 답변 생성 시 그러한 특정 단어에 초점을 맞출 수 있도록 하 는 디코딩을 위해 제 3 장의 내용을 보다 발전시킨다. 2부에서는 사회적 상식을 결합한 대화 데이터셋을 구축하는 방법론들을 살펴 본다. 제 5 장에서는 기존 대화 데이터셋들이 지닌 긍정성 관련 편향을 분석하고 이 를 상쇄하여 대화형 인공지능을 보다 친사회적으로 만들기 위해 사회 규범을 반영 한 ProsocialDialog 데이터셋을 소개한다. 제 6 장에서는 사전 훈련된 언어 모델 과 상식 지식 그래프(commonsense knowledge graph)를 사용하여 기존 대화 데 이터셋의 품질과 규모를 크게 개선하는 SODA 데이터셋을 제안한다. 그리고 이 를 학습시킨 대화 모델 COSMO가 기존 대화 모델들에 비해 유의미하게 성능이 뛰 어나다는 점을 보인다. 마지막으로, 제 7 장에서는 향후 대화형 인공지능 분야에 서 유망한 연구 방향을 다루며 본 학위 논문을 마무리한다.Abstract Acknowledgements 1 Chapter 1 Introduction 3 1.1 Thesis Overview 4 Chapter 2 Background 8 2.1 Preliminary 8 2.1.1 The Sub-fields of Machine Dialogue 8 2.1.2 Types of Neural Dialogue Models 10 2.1.3 Training and Response Generation 10 2.1.4 Evaluation of Conversational Agents 11 2.2 Related Work 11 2.2.1 Applying Pragmatics to Text Generation 11 2.2.2 Endowing Persona and Improving Consistency 12 2.2.3 Displaying Empathy and Recognizing Emotion Causes 13 2.2.4 Ensuring Dialogue Safety 14 2.2.5 Methods for Creating Dialogue Datasets 15 Part I Social Cognition-inspired Response Generation 17 Chapter 3 Improving Persona Consistency via Pragmatic Self-Consciousness 18 3.1 Introduction 18 3.2 Insensitivity to Contradictory Words in Existing Persona-based Agents 21 3.2.1 Analysis of Contradictory Utterances 23 3.3 Approach 24 3.3.1 Modeling the Public Self-Consciousness 24 3.3.2 Learning to Select Distractors 26 3.4 Experiments 29 3.4.1 Datasets 29 3.4.2 Experimental Setting 29 3.4.3 Quantitative Results 30 3.4.4 Human Evaluation 33 3.4.5 Consistency for Dialogue Context 34 3.4.6 Controlling the Self-Conscious Agent 35 3.5 Summary 36 Chapter 4 Improving Empathy by Focusing on Emotion Causes via Perspective-taking 39 4.1 Introduction 39 4.2 Identifying Emotion Cause Words with Generative Emotion Estimation 41 4.2.1 Why Generative Emotion Estimator 42 4.2.2 Training to Model Emotional Situations 43 4.2.3 Recognizing Emotions 44 4.2.4 Weakly Supervised Emotion Cause Word Recognition 44 4.3 Controlling the RSA framework for Focused Empathetic Responses 45 4.3.1 The Rational Speech Acts Framework 45 4.3.2 Endowing Word-level Control for RSA toFocus on Targeted Words in Context 46 4.4 EmoCause: Emotion Cause Words Evaluation Set 49 4.4.1 Collecting Annotations 49 4.4.2 Analysis 50 4.5 Experiments 51 4.5.1 Datasets and Experiment Setting 51 4.5.2 Weakly-Supervised Emotion Cause Word Recognition 53 4.5.3 Empathetic Response Generation 54 4.6 Summary 58 Part II Social Commonsense-infused Dataset Construction 59 Chapter 5 Improving Prosociality with Constructive Negative Feedback based on Social Norms 60 5.1 Introduction 60 5.2 Prosociality and Receptiveness in Conversational Agents 63 5.2.1 Prosocial Responses with Rules-of-thumb 63 5.2.2 Improving Receptiveness in Dialogues 64 5.2.3 Fine-grained and Inclusive Safety Labeling 64 5.2.4 Whose Prosociality Is It Anyway 65 5.3 ProsocialDialog 66 5.3.1 Collecting Problematic Situations 66 5.3.2 Collecting Dialogues 67 5.3.3 Collecting Dialogue Safety Labels 69 5.3.4 Analysis of ProsocialDialog 69 5.4 Building Socially Responsible Dialogue Agents with ProsocialDialo 71 5.4.1 Canary: A Dialogue Safety Detection Model Generating RoTs 72 5.4.2 Prost: A Prosocial Dialogue Agent Grounded in RoTs 72 5.5 Experiments on ProsocialDialog 74 5.5.1 Dialogue Safety Classification & Rule-of-thumb Generation 74 5.5.2 Response Generation via Prost 75 5.6 Generalizability of Prost and Canary 77 5.6.1 Generalizing to Real-world Toxic Phrases 77 5.6.2 Improving Prosociality of Pre-trained Language Models with Canary 78 5.7 Societal and Ethical Considerations 80 5.8 Limitations 83 5.9 Summary 84 Chapter 6 Improving Generalizability via Million-scale Dialogue Distillation with Social Commonsense 85 6.1 Introduction 85 6.2 CO_3: A Contextualization Framework for Conversation Distillation using Commonsense 88 6.2.1 Inspiration Behind CO_3 88 6.2.2 Commonsense Knowledge Graph 89 6.2.3 Commonsense Knowledge Narrative 89 6.2.4 Narrative Conversation 90 6.3 Soda: A Million-scale Social Dialogue Dataset 92 6.3.1 Post-processing the Conversations 92 6.3.2 Comparing Soda with Human-authored Dialogues 94 6.3.3 Do We Need Contextualization 99 6.4 Cosmo: A Socially Situated Conversation Model 99 6.5 Generalizability of Cosmo 100 6.5.1 Out-of-domain Setting 101 6.5.2 One-sided Out-of-domain Setting 102 6.5.3 In-domain Setting 103 6.6 Limitations 104 6.7 Summary 106 Chapter 7 Conclusion 108 7.1 Summary of Contributions 108 7.2 Future Directions 109 요약 112 Appendix A Supplementary Details for Improving Persona Consistency 113 A.1 Results on Variants of Distractor Selection 113 A.2 Implementation Details 114 A.3 Dialogue Examples 116 Appendix B Supplementary Details for Improving Empathy 118 B.1 Implementation Details 118 B.2 Emotion Classification 120 B.3 Details of EmoCause Evaluation Set 120 Appendix C Supplementary Details for Improving Prosociality 123 C.1 Details of Constructing ProsocialDialog 123 C.1.1 Collecting Problematic Situations 123 C.1.2 Drafting Dialogue Openers 125 C.1.3 Collecting Dialogues 126 C.1.4 Collecting Dialogue Safety Labels 127 C.1.5 Additional Dataset Statistics 129 C.1.6 Worker Statistics 131 C.2 Details of Model Training 132 C.2.1 Canary 132 C.2.2 Prost 133 C.2.3 Details of Training Computation 134 C.3 Details of Experiments 134 C.3.1 Dialogue Safety Classification 134 C.3.2 Rule-of-thumb Generation 134 C.3.3 Response Generation 135 C.4 Details of zero-shot experiments 136 C.4.1 Generalizing to Real-world Toxic Phrases via Prost 136 C.4.2 Improving Prosociality of Pre-trained Language Models with Canary 137 C.5 Dialogue Dataset Descriptions 137 Appendix D Supplementary Details for Improving Generalizability 143 D.1 Details of CO_3 143 D.1.1 Commonsense Knowledge Narrative 143 D.1.2 Narrative Conversation 144 D.2 Details of Soda 144 D.2.1 Post-processing the Conversations 144 D.2.2 Comparing Soda with Human-authored Dialogues 148 D.3 Details of Cosmo 149 D.4 Experiment Details 149 D.5 Dialogue Dataset Descriptions 152박

Concomitant Talocalcaneal Coalition as a Risk Factor for Early Relapse Following Ponseti Treatment of Idiopathic Clubfoot

Concomitant talocalcaneal coalition (TCC) in idiopathic clubfeet is not well documented in the literature. The purpose of this study was to describe our experience with very early relapsing idiopathic clubfeet associated with TCC. Although cases have been successfully treated with the Ponseti casting method, all recurred within 2 months of removing the final cast. A single-centre cohort of twelve feet in eight patients treated by a single surgeon between 2006 and 2020 was investigated retrospectively. Recurred cavus with variable degrees of equinus was the earliest findings noted. TCC was incidentally detected during the open reduction of the earliest three feet in our series. Afterwards, ultrasonography was advised as a screening tool for detecting an associated anomaly; however, only the use of magnetic resonance imaging (MRI) was 100% accurate in diagnosing concurrent TCC. All coalitions were cartilaginous and the posterior facet was most commonly involved facet. The average age was 18 months for the coalition resection and open reduction of a dislocated talonavicular joint, and the average duration of follow-up was 52 months. None of the patients showed clinical signs of relapse at the latest follow-up. We recommend that an associated TCC should be considered in very early relapsing idiopathic clubfoot cases.ope

Use of Allograft in Dega Acetabuloplasty

Purpose: Use of auto-iliac bone in acetabuloplasty in children is the standard method, however this has some problems such as the possibility of injury to the iliac apophysis, potential iliac deformity after operation, and the difficulty in getting enough size of bone. The purpose of this study was to examine the results of use of allobone in Dega osteotomy in children. Materials and Methods: 13 hips in 12 children with acetabular deficiency were included for the study. The mean age at the time of the operation was 7+3 years (range, 4~10+6 years). 7cases were of acetabular dysplasia associated with cerebral palsy and 6 cases were of developmental acetabular dysplasia. Acetabular index (AI) and center-edge angle (CEA) were measured before operation, after immediate operation, postoperative 6 months and postoperative 1 year. Results: There were no postoperative complications, such as deep infection, nonunion, delayed union, graft loss during the follow-up period. The average AI after immediate operation was 2 3 . 1°and CEA was 12.5°. The average AI at postoperative 1 year was 26.6°and CEA was 14.3°. There were no significant differences after immediate operation, postoperative 6 months and postoperative 1 year. Conclusion: Allobone graft in the acetabular reconstruction is thought to be useful for children whose enough bone can not be obtained.ope

Outcome of Femoral Varus Derotational Osteotomy for the Spastic Hip Displacement: Implication for the Indication of Concomitant Pelvic Osteotomy

No previous studies have suggested a reliable criterion for determining the addition of a concomitant pelvic osteotomy by using a large patient cohort with quadriplegic cerebral palsy and a homogenous treatment entity of femoral varus derotational osteotomies (VDRO). In this retrospective study, we examined our results of hip reconstructions conducted without a concomitant pericapsular acetabuloplasty in patients with varying degrees of hip displacement. We wished to investigate potential predictors for re-subluxation or re-dislocation after the index operation, and to suggest the indications for a simultaneous pelvic osteotomy. We reviewed the results of 144 VDROs, with or without open reduction, in 72 patients, at a mean follow-up of 7.0 (2.0 to 16.0) years. Various radiographic parameters were measured, and surgical outcomes were assessed based on the final migration percentage (MP) and the Melbourne Cerebral Palsy Hip Classification Scale (MCPHCS) grades. The effects of potential predictive factors on the surgical outcome was assessed by multivariate regression analysis. A receiver operating characteristic (ROC) curve analysis was also performed to determine whether a threshold of each risk factor existed above which the rate of unsatisfactory outcomes was significantly increased. In total, 113 hips (78.5%) showed satisfactory results, classified as MCPHCS grades I, II, and III. Thirty-one hips (21.5%) showed unsatisfactory results, including six hip dislocations. Age at surgery and preoperative acetabular index had no effects on the results. Lower pre- and postoperative MP were found to be the influential predictors of successful outcomes. The inflection point of the ROC curve for unsatisfactory outcomes corresponded to the preoperative MP of 61.8% and the postoperative MP of 5.1%, respectively; these thresholds of the pre- and postoperative MP may serve as a guideline in the indication for a concomitant pelvic osteotomy. Our results also indicate that the severely subluxated or dislocated hip, as well as the hip in which the femoral head is successfully reduced by VDRO but is still contained within the dysplastic acetabulum, may benefit from concomitant pelvic osteotomy.ope

Changes in Gait Pattern After Surgeries for Equinus Gait in Cerebral Palsy Spastic Hemiplegia

Purpose: To evaluate the effects of surgery for an equinus gait on the kinematic and kinetic parameters of ankle and proximal joints in cerebral palsy spastic hemiplegics. Materials and Methods: Sixteen spastic hemiplegic patients who had undergone a surgical correction for equinus were enrolled in this study. The kinematic and kinetic parameters during gait were assessed using computed gait analysis before and after surgery. Results: Postoperatively, the ankle range of motion was significantly improved and the temporospatial parameters were not significantly changed. The angular movement of the ankle joint and pelvis were improved. However, the kinetic parameters of the ankle joint were unaffected. In patients with a recurvatum knee gait pattern prior to surgery, the kinematic and kinetic parameters of the knee joint were significantly improved. The angular movements of pelvis after surgery were improved in patients with pelvic external rotation preoperatively. Conclusion: Genu recurvatum and pelvic external rotation during the gait in spastic hemiplegic CP might be improved by a surgical correction of the equinus deformity.ope

Architecture of the Triceps Surae Muscles Complex in Patients with Spastic Hemiplegia: Implication for the Limited Utility of the Silfverskiöld Test

The Silfverskiöld test has long been used as an important tool for determining the affected muscles of the triceps surae in patients with equinus deformity. However, the test may not reflect the altered interactions between the muscles of the triceps which are affected by spasticity. The purpose of this study was to compare the architectural properties of the triceps surae muscles complex using ultrasonography, between hemiplegic patients and typically-developing children. Specifically, we wished to examine any differences in the architecture of the three muscles with various angle configurations of the knee and ankle joints. Ultrasound images of the medial gastrocnemius, lateral gastrocnemius, and soleus were acquired from paretic (group I) and non-paretic (group II) legs of ten patients and the legs (group III) of 10 age-matched normal children. A mixed model was used to evaluate the differences in the measurements of muscle architecture among the groups and the effects of various joint configurations on the measurements within the muscles. Compared to the results of measurements in groups II and III, the fascicle length was not different in the medial gastrocnemius of a paretic leg but it was longer in the lateral gastrocnemius and shorter in the soleus; the pennation angle was smaller in both medial and lateral gastrocnemii and was not different in the soleus; and the muscle thickness was found to be reduced in the three muscles of the paretic leg. Contrary to the observations in both the medial and lateral gastrocnemii, the fascicle length was increased and the pennation angle was decreased in the soleus with an increase of knee flexion. Through the current simulation study of the Silfverskiöld test using ultrasonography, we found that the changes detected in the architectural properties of the three muscles induced by systematic variations of the position at the ankle and the knee joints were variable. We believe that the limited utility of the Silfverskiöld test should be considered in determining an appropriate operative procedure to correct the equinus deformity in patients with altered architecture of the muscles in conditions such as cerebral palsy, as the differing muscle architectures of the triceps surae complex may affect the behavior of the muscles during the Silfverskiöld test.ope

Hip-Spine Syndrome in Patients With Spinal Cord Injuries: Hyperlordosis Associated With Severe Hip Flexion Contracture

Aim: Spinal cord injury (SCI)-related flaccid paralysis may result in a debilitating hyperlordosis associated with a progressive hip flexion contracture. The aim of this study was to evaluate the correction of hip flexion contractures and lumbar hyperlordosis in paraplegic patients that had a history of spinal cord injuries. Methods: A retrospective review was performed on 29 hips of 15 consecutive patients who underwent corrective surgeries for severe hip flexion deformity from 2006 to 2018. The mean age at surgery was 10.1 years (2.7 to 15.8), and the mean follow-up was 68 months (7 to 143). Relevant medical, surgical, and postoperative information was collected from the medical records and radiographs. Results: Improvements were seen in the mean hip flexion contracture (p < 0.001) with 100% hip correction at surgery and 92.1% at the latest follow-up. Mean lumbar lordosis decreased (p = 0.029) while the mean Cobb angle increased (p = 0.001) at the latest follow up. Functional score subdomains of the Spinal Cord Independence Measure, Functional Independence Measure, and modified Barthel activities of daily living (ADL) scores remained the same at the final follow-up. Conclusion: For paraplegic SCI patients, we found an association between treating the hip flexion contracture and indirect correction of their lumbar hyperlordosis. We recommend the surgeon carefully examine the hip pathology when managing SCI-related spinal deformities, especially increased lumbar lordosis.ope

서울·경기지역을 중심으로

학위논문(박사) -- 서울대학교대학원 : 인문대학 고고미술사학과(고고학전공), 2023. 2. 김장석.Unified Silla strengthened management and control of the state in various sectors of society by establishing a highly centralized system. As part of this, it has been suggested that the production and distribution of pottery were managed or controlled centrally by Unified Silla, and the spread and standardization hypothesis of Unified Silla pottery has been used to support this view archaeologically. However, this explanation is excessively state-centric, overlooking the diverse ways in which various economic agents may have produced and distributed pottery. As it is expected that highly complex societies will be characterized by varied and complicated forms of economic organization, it is necessary to consider actors other than the state in order to understand the political economy of Unified Silla. Therefore, this study focuses on the private sector as a major economic agent in comparing and reviewing the production and distribution of pottery by the state and within the private sector in order to infer the political and economic implications of pottery production and distribution in Unified Silla. In this study, the excavation patterns of Unified Silla pottery were identified in Seoul and Gyeonggi province, the level of morphological variation was compared with that of Gyeongju, and the distribution range of pottery was investigated through geochemical analysis (INAA and pXRF). The results of these analyses confirm that stamped-design pottery, which is considered a representative type of Unified Silla pottery, was excavated almost exclusively at fortress sites in Seoul and Gyeonggi province and only one production site has been discovered thus far. This pattern is thought to reflect the special function and characteristics of stamped-design pottery in Unified Silla pottery. Considering its highly decorative form and limited production-consumption patterns, stamped-design pottery likely held a higher social value than Mumun pottery, which was widely used in everyday life. More specifically, it is proposed that stamped-design pottery may have been used as utilitarian, serving, and ritual vessels by local officials in fortresses. As a result of reviewing the chronology of Unified Silla pottery in Gyeongju and comparing it with pottery excavated from fortresses in Seoul and Gyeonggi province, Unified Silla pottery in Seoul and Gyeonggi shows a relatively similar shape to those in Gyeongju. On the other hand, in the case of settlements, the level of morphological variation is much more diverse than in the Gyeongju area, and in particular, in the case of bowls or jars, morphological variation is observed among each site. The results of geochemical analysis of Unified Silla pottery in Seoul and Gyeonggi province support the results of the morphological analysis. Pottery from Sadang-dong, Seoul and pottery from Hoamsan Fortress and Achasan Fortress were not distinguishable geochemically, suggesting that pottery produced at Sadang-dong was widely distributed. On the other hand, analysis of pottery from settlement sites reveals that pottery clearly differentiated at the site level. Taken together, it is suggested that a government production-distribution system, centered on fortresses, and a private production-distribution system, centered on settlements, coexisted in Seoul and Gyeonggi province during the Unified Silla Period. This dual distribution network was likely the result of decision-making by the state and private sector producers/consumers that took into consideration their respective needs, objectives, and economic levels. In the case of the state, it is suggested that a small number of base facilities produced pottery for official use and distributed it to fortresses in order to stably supply high-quality pottery needed for fortresses and achieve economies of scale. Since there was a water transportation system in place for tax collection and transportation, it is possible that the cost of long-distance transportation was not high. On the other hand, in the private sector, production-distribution patterns of settlement units may have appeared because transportation costs acted as the biggest constraint in the procurement of daily-use pottery. Consumers at the individual household level would have likely preferred to avoid high transport costs associated with procuring pottery from distant locations, unless the pottery held a special function or was a luxury item. Excessively state-centric interpretations are highly likely to result in incomplete understandings of the complexly differentiated Unified Silla society. The more complicated society was, the more diverse avenues of production and distribution coexisted, and in the case of Unified Silla, there were major differences in production and distribution modes between the state and the private sector. As these systems of production and distribution likely emerged as a result of both the function of pottery and its basic physical properties, it is thought that different types of goods would have been produced and distributed in different ways, and thus, will likely leave other varied traces on the material culture.통일신라는 고도의 중앙집권적 체제를 구축함으로써 이를 바탕으로 사회 여러 부문에 국가의 관리와 통제를 강화하였다. 그러한 맥락에서 토기 또한 통일신라에 의해 생산과 유통이 관리 또는 통제되었던 것으로 추정되었으며, 통일신라토기의 확산과 규격화 가설은 이를 고고학적으로 뒷받침해왔다. 그러나 이는 과도한 국가중심적 설명으로, 다양한 경제주체가 다양한 방식으로 토기를 생산하고 유통하였을 가능성을 간과한 것이다. 고도로 복합화된 국가단계의 사회에서는 다종다양한 경제적 양상이 복잡하게 개재되어 있을 것으로 예상되는 만큼, 통일신라의 정치경제를 이해하기 위해서는 국가가 관장하는 영역 외의 양상을 함께 살펴보는 것이 필요하다. 따라서 본 연구는 주요 경제주체 중 하나로 민간부문에 주목하여 국가와 민간에서의 토기생산과 유통을 비교검토하고 그 정치경제적 의미를 추론하고자 하였다. 이를 위해 가장 자료가 풍부한 서울·경기지역을 대상으로 통일신라토기의 출토 양상을 파악하고, 형태적 변이의 수준을 경주지역과 비교하였으며, 지구화학적 분석(INAA 및 pXRF)을 통해 토기의 유통범위를 검토하였다. 그 결과, 통일신라토기를 대표하는 것으로 알려진 인화문토기는 서울·경기지역에서 산성유적으로 출토가 제한되었고, 현재까지 알려진 생산유적도 단 한 곳에 불과한 것으로 확인되었다. 이것은 통일신라토기 중 인화문토기의 특수한 기능과 성격을 반영한 결과라고 할 수 있다. 높은 장식성과 제한된 생산-소비양상을 고려하면 일상적으로 광범위하게 사용되었던 무문양토기에 비해 인화문토기는 사회적으로 보다 높은 가치를 가지고 있었을 것으로 생각되며, 구체적으로는 산성유적을 중심으로 출토된다는 점에서 지방관의 생활용기, 접대용기, 의례용기 등으로 사용되었던 것으로 추정된다. 경주지역 통일신라토기 편년을 재검토하고 이를 서울·경기지역의 토기상과 비교한 결과, 서울·경기지역의 통일신라토기 중 산성유적 출토품은 경주지역과 상대적으로 유사한 형태를 보이는 편이다. 반면, 취락유적 출토품의 경우 경주지역에 비해 형태적 변이의 수준이 훨씬 다양하고, 특히 완이나 호류는 유적별로 뚜렷한 형태적인 차이가 확인되었다. 서울·경기지역 통일신라토기에 대한 지구화학적 분석결과는 형태분석 결과를 뒷받침한다. 서울 사당동 토기와 호암산성 및 아차산성 토기는 지구화학적으로 변별되지 않아 사당동 토기가 분배되었을 가능성을 시사하지만, 취락유적에 대한 분석에서는 유적 단위로 뚜렷하게 변별되는 양상이 확인되었기 때문이다. 이를 종합하면 통일신라시대 서울·경기지역에는 산성을 중심으로 한 관영생산-분배체제와 취락을 중심으로 한 민영생산-유통체제가 공존하고 있었던 것으로 추정된다. 국가와 민간이라는 경제주체에 의한 이러한 이중의 유통망은 각자의 필요와 목적, 경제수준 등을 고려한 의사결정의 결과일 것이다. 국가의 경우, 산성에 필요한 양질의 토기를 안정적으로 공급하고, 규모의 경제를 달성하고자 소수의 거점시설에서 관용토기를 생산하고 산성으로 분배하였던 것으로 추정된다. 여기에 조세운반을 위한 수운체제가 마련되어 있었기 때문에 장거리 운반에 따른 비용문제도 크지 않았을 가능성이 있다. 반면 민간부문은 일상용토기의 조달에서 운반비용이 가장 큰 제약조건으로 작용하여 유적 단위의 생산-유통양상이 나타난 것으로 여겨진다. 특수한 기능이나 사치품이 아닌 이상, 개별 가구 수준에서 높은 운반비용을 감수하면서 원거리에서 토기를 조달하였을 가능성은 낮기 때문이다. 복잡하게 분화되었을 통일신라사회에서 과도한 국가중심적 해석은 당시 사회에 대한 불완전한 이해를 야기할 수 있다. 복잡한 사회일수록 다층적인 생산과 유통망이 다양하게 공존하기 때문이다. 통일신라의 경우에는 국가와 민간에서 생산과 유통방식에서 큰 차이가 있었다. 여기에는 토기의 물리적 특성을 비롯하여 용도와 성격이 반영된 것으로 판단되는 만큼, 재화에 따라 토기와는 또다른 다양한 방식으로 생산 및 유통되었을 것이며, 이러한 양상은 물질문화에 복잡하게 개재되었을 것이다.I. 서론 1 II. 연구목적과 방법론 8 1. 연구목적과 이론적 검토 8 1) 연구목적 8 2) 토기의 교환에 대한 이론적 검토 11 2. 한국고고학의 통일신라토기에 대한 인식 18 1) 통일신라토기와 인화문토기 19 2) 통일신라토기의 편년과 지역성 25 3) 통일신라토기의 생산과 유통 35 3. 연구방법론 39 1) 분석대상 39 2) 연구방법론 53 III. 통일신라토기 출토양상: 인화문토기와 무문양토기의 비교 65 1. 서울·경기지역 통일신라토기의 출토양상 65 2. 서울·경기지역 인화문토기 출토 주거지의 특징 73 3. 소결 79 IV. 경주지역 토기의 편년 81 1. 토기편년의 전제와 방법 81 1) 생활유적 토기의 시간적 위치에 개입된 변수들 81 2) 방사성탄소연대의 활용 가능성 84 3) 편년 방법 86 2. 경주지역 토기의 변화상 88 1) 대부완 88 2) 개 97 3) 완 104 4) 단경호류 108 5) 단경병류 118 6) 기종별 병행관계 122 3. 경주지역 인화문의 변화상 124 1) 시기별 대부완의 인화문 분포 양상 124 2) 시기별 개의 인화문 분포 양상 126 3) 경주지역 인화문의 변화상 127 V. 경주지역 토기편년으로 본 서울·경기지역 통일신라토기 128 1. 기종별 양상 129 1) 식기류 129 2) 저장용기류 172 2. 문양 구성: 인화문과 선각문 181 3. 소결 186 1) 서울·경기지역 토기의 지역성 186 2) 형태와 문양으로 본 서울·경기지역 토기의 생산과 유통 188 VI. 지구화학적 분석을 통해 본 통일신라토기의 유통 191 1. 한강유역 통일신라토기에 대한 INAA 분석 193 2. 경기 남부 통일신라토기에 대한 pXRF 분석 199 1) INAA와 pXRF 분석결과 비교 201 2) 경기 남부 통일신라토기의 수계에 따른 변별 양상 207 3) 유적별 변별 기준: 판별분석 분류정확도 210 4) pXRF를 통해 본 경기 남부 통일신라토기의 유적별 변별 양상 212 3. 소결 218 VII. 통일신라토기의 생산과 유통 222 1. 통일신라 인화문토기의 성격 223 2. 통일신라토기 생산과 유통의 다양성 228 1) 서울·경기지역 지방거점(산성)에서 소비된 토기의 생산과 유통 229 2) 서울·경기지역 일반취락에서 소비된 토기의 생산과 유통 231 3) 토기생산과 유통의 경제적 의사결정 233 4) 수공업생산과 유통의 다양성 237 VIII. 결론 241 참고문헌 245 Abstract 303박

국내 흰줄숲모기의 분포, 발생 및 흡혈행동 연구

학위논문 (박사)-- 서울대학교 대학원 : 농생명공학부, 2017. 2. 이시혁.Aedes albopictus is an invasive mosquito that can be found in all continents. This species, considered as a secondary vector of Dengue virus, has recently been suggested to play a role in the transmission of Zika virus in several countries bordering Brazil. This mosquito originated in the forests of Southeast Asia. However, this species has spread throughout the world by increased intercontinental trade during the 20th century. In this study, I surveyed the distribution, abundance and main micro habitats of Ae. albopictus in Korea. Ae. alobpictus accounted for 4% of a total of 99,625 mosquitoes examined. Ae. albopictus was first collected in May, its number increased slowly throughout August and reached the greatest number in September, then followed by rapid decrease in number during October. The larval habitats were found within 500 m distance from the bamboo forest. Most larvae were found mainly in tires (44.4% in Iksan-si, 63.6% in Damyang-gun) and artificial containers (55.6% in Iksan-si, 45.5% in Damyang-gun) including a plastic wash basin, bowl, can, styrofoam-box within the range of adult mosquito activity. Ae. albopictus activity began around sunrise with peaks in late morning (08:00–09:00) and early evening (16:00–19:00) and ended with sunset. Light intensity appears to be a major factor affecting mosquito activity: if light intensity is over some threshold, Ae. albopictus activity decreased. The main bloodmeal source of Ae. albopictus was mammals (71%) followed by birds (26%), amphibians (2%) and fish (1%). The main mammalian blood source was human (86%). This results showed that Ae. albopictus feed exclusively on human, representing the potential of this mosquito as a major vector of dengue virus, once this virus becomes domestic. In flavivirus detection, no virus was detected in the specimens of Ae. albopictus, but a total of six Japanese encephalitis virus (JEV)-positive pools were detected from Culex orientalis and Cx. pipiens except Cx tritaeniorhynchus, the main vector mosquitos of JEV. All the detected JEVs were identified as genotype V by phylogenetic analysis of the envelope gene. Our findings confirmed that a new genotype of JEV was introduced into Korea and suggested that the two mosquito species may play a role in JEV transmission. To investigate the possibility of using Wolbachia, as one of biological control strategy, I investigated the distribution of Wolbachia infection in Ae. albopictus according to geographical distribution in Korea. Over 99% of the collected mosquitoes harbored Wolbachia, and the sequence homologies of the WSP gene showed more than 98% similarity within the mosquito species. Ae. albopictus was found to be infected with two Wolbachia strains, wAlbA and wAlbB. Regional distribution analysis indicated that the wAlbA strain of Wolbachia showed more than 98% sequence similarity among Ae. albopictus collected from different regions. This study would support further functional and biocontrol-related studies of Wolbachia. Additionally, I also investigated the mosquito species composition by employing the DNA barcoding method based on the mitochondrial cytochrome c oxidase subunit I (mtCOI) gene sequence. To this end, mtCOI genes from individual mosquitoes of 25 species were sequenced, and their phylogenetic relationship was analyzed. Phylogenetic analysis showed that most mosquito species were clustered according to morphological characteristics, except for certain Anopheles species. DNA barcoding using mtCOI genes successfully identified mosquito species, and it can be used as an effective technique to complement morphological identification.Introduction 1 CHAPTER I. Abundance and distribution of Aedes albopictus 6 I-1. Distribution and Abundance of Aedes albopictus in Korea 7 Abstract 7 1. Introduction 9 2. Materials and method 11 2.1. Seasonal prevalence of Ae. albopictus 11 2.1.1. Mosquito collecting 11 2.1.2. ArcGIS geographical analysis 13 2.2. Survey of main breeding habitats of Ae. albopictus 13 2.2.1. Study sites 13 2.2.2. Mosquito collection 13 3. Results 25 3.1. Seasonal prevalence of Ae. albopictus 25 3.2. Survey of main breeding habitats of Ae. albopictus 36 4. Discussion 47 CHAPTER II. Blood-feeding behavior of Aedes albopictus: host searching activity, host preference, virus infection rate and Wolbachia infection rate 49 II-1. Daily activity of Aedes albopicus for searching hosts 50 Abstract 50 1. Introduction 51 2. Materials and Methods 53 2.1. General Description of Study Site 53 2.2. Mosquito collection 55 3. Results 56 3.1. Mosquito collecting 56 3.2. Activity of Ae. albopictus 56 3.3. The effect of light intensity on Ae. albopictus activity 59 3.4. The effect of temperature on Ae. albopictus activity 64 4. Discussion 66 II-2. Host feeding patterns of Aedes albopictus in an urban park 69 Abstract 69 1. Introduction 71 2. Materials and Methods 73 2.1. Study sites 73 2.2. Mosquito collection and identification 73 2.3. Blood meal analysis 74 2.4. Dengue virus detection 75 3. Results 76 3.1. Mosquito collection 76 3.2. Bloodmeal source identification 79 3.3. Dengue virus detection 82 4. Discussion 83 II-3 Detection of Japanese encephalitis virus (JEV) in Aedes albopictus collected from the high risk area 86 Abstract 86 1. Introduction 88 2. Materials and Methods 91 2.1. Mosquito collection 91 2.2. Virus detection 93 2.3. Nucleotide sequencing and phylogenetic analysis 94 3. Results 98 3.1. Mosquito collection 98 3.2. Virus detection and phylogenetic analysis 101 4. Discussion 110 II-4. Wolbachia infection rate in Aedes albopictus collected from different geographical locations in Korea 114 Abstract 114 1. Introduction 116 2. Materials and Methods 119 2.1. Mosquito collection 119 2.2. DNA extraction and Polymerase Chain Reaction (PCR) 122 2.3. Nucleotide sequencing and phylogenetic analysis 122 3. Results 125 3.1. Survey of Wolbachia in Ae. albopictus using the WSP gene 125 3.2. Classification of Wolbachia in Ae. albopictus according to geographical distribution 127 4. Discussion 131 Literatures Cited 133 Appendix 148 Abstract in Korean 157Docto