• Journal of the Korean Society for Precision Engineering
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• v.19 no.12
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• pp.13-19
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• 2002

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.50 no.3
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• pp.153-160
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• 2024

Objectives: This study identifies factors for differential diagnosis among lesions by retrospectively comparing panoramic and cone-beam computed tomography images and analyzing the characteristics of lesions associated with impacted mandibular third molars (IMTs). Materials and Methods: A retrospective cohort study was conducted in patients who simultaneously underwent IMT extraction surgery and related benign tumor resection or cyst enucleation at our institution from 2017 to 2021. To compare the characteristics of each group, two comparative analyses were conducted. The first comparison considered the most frequently observed lesions associated with IMTs: dentigerous cysts, odontogenic keratocysts (OKCs), and ameloblastoma. The second comparison involved placing dentigerous cysts, which have a relatively low recurrence rate, into group A and placing OKC, ameloblastoma, and odontogenic myxoma, which have high recurrence rates, into group B. Results: Significant differences in the size of the lesion were found in the order of ameloblastoma, OKC, and dentigerous cyst (P<0.05). The buccolingual width of ameloblastoma differed significantly from that of the other groups, with no significant difference observed between the OKCs and dentigerous cysts (P=0.083). Conclusion: Patient age and lesion size differed significantly among lesion types associated with IMTs, with younger age and larger lesions for OKCs and odontogenic tumors. OKCs are likely to have a larger mesiodistal width than dentigerous cysts. The buccolingual width of ameloblastomas was larger than those of dentigerous cysts and OKCs.

• Journal of Educational Research in Mathematics
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• v.9 no.1
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• pp.321-332
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• 1999

This article made overtures of the relationship between interactive mathematics texts nd the prototype design of computer application with Computer Algebra System Math. Engine, linking together in the school mathematics. School teachers and researchers would try to construct mathematical materials with computers in educating students in the middle and high school grades. As the individual users come to manage hyper-media materials, so they meet with the problem of 'Who does control?'A mass user would be concerned with interactive mathematics materials directly or off-line at realtime and manipulate the process of problem-solving symbolically with MathView/sup 11)/ and ON-Math/sup 12)/. Discussion was made in developing the factor in the domestic situation and reaching out their hands for it. In conclusion, a user may reform the information of math-curriculum limitedly.

• Steel and Composite Structures
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• v.50 no.2
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• pp.237-247
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• 2024

Research on interfacial crack formation in orthotropic bi-materials has experienced a notable increase in recent years, driven by growing concerns about structural integrity and reliability. The existence of a crack at the interface of bi-materials has a substantial impact on mechanical strength and can ultimately lead to fracture. The primary objective of this article is to introduce a comprehensive analytical model and establish stress relationships for investigating interfacial crack between two non-identical orthotropic materials with desired crack-fiber angles. In this paper, we present the application of the Interfacial Maximum Tangential Stress (IMTS) criterion, in combination with the Reinforcement Isotropic Solid (RIS) model, to investigate the behavior of interfacial cracks in orthotropic bi-materials under mixed-mode I/II loading conditions. We analytically characterize the stress state at the interfacial crack tip using both Stress Intensity Factors (SIFs) and the T-stress term. Orthotropic materials, due to their anisotropic nature, can exhibit complex crack tip stress fields, making it challenging to predict crack initiation behavior. The secondary objective of this study is to employ the IMTS criterion to predict the crack initiation angle and explore the notable impact of the T-stress term on fracture behavior. Furthermore, we validate the effectiveness of our approach in evaluating Fracture Limit Curves (FLCs) for interfacial cracks in orthotropic bi-materials by comparing our FLCs with relevant experimental data from existing literature.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.4
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• pp.11-20
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• 1996

1994년 9월7일부터 15일까지 9일간 미국 Chicago에서 International Manufacturing Technogy Show(IMTS 94)가 개최되어 수십만명이 Show를 보기 위해서 세계 각국으로부터 모여들고 있었다. 필자도 그 중 한사람이었으며 Gidding & Lewis사의 전시 Booth에 도착했을 때 어떤 기계의 Demo 를 구경하기 위한 인파가 꽉 차 있는 것을 보았다. 먼 곳에서 보니 1969.7.20 미국에서 달에 쏘아올려 Neil Armstrong이 조종한 Apollo ll 우주선과 흡사한 모습의 기계가 보였다. 상하 두 Platform 사이를 6개의 다리로 지지되어 있고 상부 Platform의 하축에 공구의 Spindle이 부착되어 있었다. 이 기계를 VARIAX라고 부르고 미래의 공작기계가 이모양이 될 것이라고 설명하고 있었다.

• Proceedings of the Korea Multimedia Society Conference
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• 1998.04a
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• pp.438-443
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• 1998

최근 멀티미디어 응용 기술을 기반한 컴퓨터 교육 매체 개발이 활발히 진행되어 왔다. 본 연구에서 수준별 개별 학습으로 학습 효과를 극대화하기 위한 지능형 멀티미디어 교습 시스템(IMTS)을 제안한다. 제안하는 시스템은 활발한 상호작용으로 학습자의 상태를 진단하고, 개별 학습자 수준을 고려한 동적인 학습 과정을 능동적으로 수립하면서 교습 활동을 전개해 나간다. 제안하는 시스템은 다양한 학습자 수준과 상태에 따른 적응적 교습 과정을 수행하기 위하여 학습자 모델을 유지 관리한다. 그리고 다수의 학습자를 위한 원격 교습 과정을 수행하기 위하여 학습자 모델을 유지 관리한다. 그리고 다수의 학습자를 위한 원격 교습 시스템을 효율적으로 운영하기 위하여 교습 과정에 필요한 모든 모듈을 에이전트로 대체하여 클라이언트/서버 환경에서 교습 활동을 효율적으로 수행하도록 설계하였다.

• Communications of Mathematical Education
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• v.10
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• pp.505-517
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• 2000

수학 학습에서 컴퓨터와 계산기의 활용은 시각화의 강화로부터 직관력과 사고력의 향상을 가져왔다. 컴퓨터 대수체계(Computer Algebra System)가 탑재된 수학 학습용 컴퓨터 프로그램과 계산기가 활발히 사용되고 있으며, 교수매체로서의 활용은 지식 정보전달 체계와 학습자의 지식 구성방법에 새로운 패러다임을 형성하였다. 특히 수학학습용 그래픽 계산기(Graphing Calculator)는 휴대형(Hand-held Technology)으로 학습공간의 이동(Mobil Education)이 가능하며, 수학학습 전용기라는데 의미를 둘 수 있다. Symbolic Graphing Calculator를 활용한 수업에서 학습자는 계산기를 가지고, 기호연산 실행 조작을 통해 자신의 사고과정을 표현하고, Symbolic Graphing Calculator는 실행 조작에 즉각적으로 과정과 결과를 제공하며, 다른 표상과 상호작용을 함으로써 학습자 스스로의 규제가 강화된 과정을 통해 지식을 구성하게 된다. 이때 교사는 지식 정보전달 체계인 대화형 실행매체(IMTs)를 작성하여 학습자의 지식 형성에 안내자의 역할을 하게 된다. 이번 워크샵에서는 CASIO fx 2.0을 활용한 교실 수업모형을 그래프 표상과 연계한 방정식의 풀이과정을 통해 알아본다.

• Journal of Gastric Cancer
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• v.15 no.1
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• pp.64-67
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• 2015

Inflammatory myofibroblastic tumors (IMTs) of the stomach are extremely rare in adults, and their oncologic prognosis is not well understood. We present a 28-year-old man with a proximal gastric IMT. The patient visited the emergency department of Yeouido St. Mary's Hospital with syncope and hematemesis. Hemoglobin levels were <5.5 g/dl. Gastric fibroscopy showed a protruding mass $4{\times}4cm$ in size, with central ulceration on the posterior wall of the fundus and diffuse wall thickening throughout the cardia and anterior wall of the upper body. Endoscopic biopsy revealed indeterminate spindle cells, along with inflammation. Given the risk of rebleeding, an operation was performed despite the uncertain diagnosis. Because the mass was circumferential, laparoscopic proximal gastrectomy and double-tract anastomosis were performed to ensure a safe resection margin. The pathological diagnosis was consistent with an IMT originating from the stomach, although the tumor was negative for anaplastic lymphoma kinase gene mutation.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.30 no.1
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• pp.57-60
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• 2019

Inflammatory myofibroblastic tumor (IMT) is a rare benign tumor, that is composed of myofibroblastic spindle cells with inflammatory cells. IMTs usually occur in lungs, intestine organs, orbits and paranasal sinuses, however, it may rarely be seen in the larynx. We present two cases of patients with laryngeal IMT that had different causes and prognosis.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.67
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• pp.209-231
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• 2015

The accurate national trade statistics can show the real nation's trade situation, and contribute to setting up the national's trade plans and corporate's strategies. This study researches the differences between trade statistics and actual trade record among the national and international statistics and suggests improvement plans to solve the problems. There are 4 types' differences among the trade statistics as follows; First, a statistical differences between Korea Customs Service and Bank of Korea by yearly US$9.6billions because of standard and boundary of trade statistics. Second, a statistical differences between Ministry of Trade, Industry and Energy and Korea Customs Service because of the time and purpose of trade statistics release. Third, a statistical differences between Korea and counterpart countries because of standard of trade statistics, intermediate countries and rules of origin. Lastly, a statistical differences between nation's statistics and corporate record because of typing errors and indirect export record. The fundamental improvement plans are Korea statistics rules like Korea Foreign Trade Rules and Korea Custom Rules, need to coincide with the international rules like IMTS, MSITS, BPM6 etc. Especially the rules of statistics related to intermediary trade, processing trade and transit trade have to revise with new BPM6 rules. In addition, a reasonable care of trade statistics from accumulation to utilization of trade information is more important than statistical regulation or system, so all persons concerned including exporters, importers, government official pay attention the statistics and cooperate together.