• Journal of Educational Research in Mathematics
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• v.13 no.2
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• pp.159-178
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• 2003

This study analyzes on the reasoning in the process of justification and mathematical problem solving in our primary mathematics textbooks. In our analyses, we found that the inductive reasoning based on the paradima-tic example whose justification is founnded en a local deductive reasoning is the most important characteristics in our textbooks. We also found that some propositions on the properties of various quadrangles impose a deductive reasoning on primary students, which is very difficult to them. The inductive reasoning based on enumeration is used in a few cases, and analogies based on the similarity between the mathematical structures and the concrete materials are frequntly found. The exposition based en a paradigmatic example, which is the most important characteristics, have a problematic aspect that the level of reasoning is relatively low In Miyazaki's or Semadeni's respects. And some propositions on quadrangles is very difficult in Piagetian respects. As a result of our study, we propose that the level of reasoning in primary mathematics is leveled up by degrees, and the increasing levels are following: empirical justification on a paradigmatic example, construction of conjecture based on the example, examination on the various examples of the conjecture's validity, construction of schema on the generality, basic experiences for the relation of implication.

• Journal of Chest Surgery
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• v.31 no.4
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• pp.380-387
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• 1998

We evaluated CT findings of bronchial carcinoid and accuracy of preoperative pathological diagnosis according to two subtypes. The subjects were 10 cases(typical;5, atypical;5), confirmed by surgery and tissue pathology. Sputum cytology(n=10), percutaneous aspiration(n=1) and bronchoscopic biopsy (n=8) were performed, preoperatively. The CT findings were analysed according to two subtypes. Typical carcinoid shows central location in all, and bronchial lumens just proximal to tumor were widened in two, whereas atypical carcinoid presented as peripheral leison in two. Among central atypical carcinoid, two cases showed flat meniscus appearance of lumen. Remaining one showed diffuse wall thickening. Intratumoral low density by necrosis was noted in one. Both subtypes show contrast enhancement. For preoperative diagnosis, sputum cytology & percutaneous aspiration were not conclusive at all. As for bronchoscopic biopsy, only 3 cases were accurately diagnosed as typical carcinoid. Typical carcinoid presented as endobronchial mass in all, whereas atypical carcinoid presented in various appearance. In all atypical & some typical carcinoid were misdiagnosed as primary lung cancer, preoperatively. However, in typical carcinoid, conservative surgery was possible. In conclusion, if there is discrepancy between CT findings & preoperative pathological diagnosis, full understanding of CT findings of bronchial carcinoid is imperative to choose appropriate surgical modality.

• Journal of The Korean Association For Science Education
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• v.28 no.6
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• pp.579-591
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• 2008

Recently, there have been studies about Typically- Perceived-Situations (TPSs) and about critical examples as a way to understand students' preconceptions with context. TPS is a situation arising immediately in one's mind when he or she thinks about the concept, while a critical example is an example that becomes the most helpful in learning the concept. We might explore how the context is involved in the process of students' conceptual understanding by examining TPSs and critical examples together. This study analyzed, through questionnaires and interviews, the characteristics of TPSs and those of critical examples that secondary students hold about 'force' and 'mechanical energy conversion.' Students' TPSs and critical examples showed different characteristics according to the concept. In a case of force that is related to everyday life, there were various situations as TPSs and critical examples. Unlike force, there were a few situations as TPSs and critical examples such as a falling ball in the case of mechanical energy conversion. Students tended to regard situations that are usually experienced and understood easily as TPSs or critical examples. On the basis of the results of this study, it is concluded that it would be a good strategy to teach science concepts for teachers to start with the TPS of a concept, to introduce the concept, and then to expose the attributes of the concept with critical examples.

• Journal of Yeungnam Medical Science
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• v.18 no.2
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• pp.239-245
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• 2001

Background: Acute idiopathic thrombocytopenic purpura(ITF) is one of the common hematologic disorders in children. Bone marrow aspiration (BMA) is often performed in children with acute ITP to rule out leukemia, aplastic anemia or other hematologic diseases. However, whether BMA is needed in children with typical clinical and hematological features of acute ITP have been questioned. This study was performed to examine the proper indication of BMA in acute childhood ITF. Materials and Methods: The medical records and BMA reports of children with the provisional diagnosis of acute ITP were reviewed from January 1984 to December 2000. Patients were divided into two groups, one with typical and another with atypical clinical and hematological features of acute ITP. Typical acute ITP group was characterized by the history of previous viral infection, well being appearance, no hepatosplenomegaly, no lymphadenopathy, normal Hb, WEC, neutrophil count and peripheral blood smear except thrombocytopenia. A platelet count of $50{\times}l0^9/L$ or lower was the cutoff level. Results: Total 120 children with the provisional diagnosis of acute ITP were included. One hundred eighteen of them were confirmed to have acute ITP by BMAs. Of these, 66 had typical and 54 had atypical features. All of typical features and 52 of 54 with atypical features of acute ITP were confirmed to have acute ITP by BMAs. Two patients with atypical features of acute ITP were diagnosed as aplastic anemia and myelodyspalstic syndrome, respectively, by BMAs. Conclusion: This study concludes that BMA is not needed for the children with typical features of acute ITP but it is needed for the children with atypical features of acute ITP to rule out other hematologic disorders.

• Journal of Chest Surgery
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• v.35 no.5
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• pp.381-386
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• 2002

Background: Bronchial carcinoids account for approximately 2% of all pulmonary tumor and consist of typical carcinoids and atypical carcinoids. An atypical carcinoids is considered to be an intermediate form of tumor between a low-grade malignant typical carcinoid and a high-grade malignant small cell lung carcinoma. There is still controversy with regard to the extent of resection and the value of systemic adjuvant therapy in atypical carcinoids. We performed a retrospective review of our experiences at Severance Hospital. Material and Method: Between 1990 and 2000, 15 patients with bronchial carcioids were operated, and 5 of these had atypical carcinoids. Histologic diagnosis was established un the criteria of WHO/IASLC(1999). Result: There were 3 pneumonectomies, 11 lobectomies, and 1 segmentectomy. In typical carcinoids, one patient had regional lymph node metastasis, and 3 patients in atypical carcinoids had mediastinal lymph node metastases. Distant metastases developed in one patient of typical carcinoid, but developed in 4 patients of atypical carcinoids(p=0.0017). The 5-year survival rate in patients with atypical carcinoids was 20%, versus the 100% 5-year survival rate observed in patients with topical carcinoids(p=0.0039). Conclusion: In atypical carcincids, because of many lymph node metastases on diagnosis and a low long-term survival rate, lobectomy constitutes a mininal procedure. Adjuvant systemic therapy is recommended fur patients with lymph node and distant metastasis.

• Journal of the Korea Computer Graphics Society
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• v.3 no.2
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• pp.65-76
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• 1997

본 논문은 인체의 최종효과기 (예: 손)가 주어진 공간상의 목표위치를 성취하도록 새로운 동작을 다수의 기존 동작을 혼합하여 생성하는 동작혼합기법을 제시한다. 전형적인 동작혼합기법에서는 동작들을 구성하는 관절커브들에 사용자가 적절한 가중치를 주고 이들의 가중치 합을 구하여 새로운 동작의 관절커브로 삼는다. 그러나 생성될 동작이 특정 제약조건 (예: 손의 최종위치)를 만족해야 될 경우에는 사용자가 성분동작에 적절한 가중치를 부여하는 것이 쉽지 않다. 따라서 본 논문은 원하는 동작의 타입 (예: 걷기, 손 뻗기) 과 동작의 최초 및 최종상태가 주어지연, 주어진 최초 및 최종상태를 만족하는 새로운 동작을 기존동작들을 혼합하여 자동적으로 생성하는 기법을 제안한다. 이 기법은 성분동작들의 집합을 연속적이고 완만한 곡면으로 표현하고 사용자가 생성하기 원하는 동작의 최초 및 최종상태를 정하면 이 곡면상에 있으면서 주어진 최초 및 최종상태를 만족하는 특정 동작을 구하여 원하는 동작으로 삼는다.

• Parasites, Hosts and Diseases
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• v.21 no.1
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• pp.87-94
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• 1983

Kala-azar는 우리나라에는 분포하지 않는 것으로 인정되고 있으나 과거 중국에서 감염되어 국내에서 관찰된 보고가 있는 질병이다. 최근에 중동 지방에서 감염되어 귀국하고 발병하였다고 생각되는 예를 보고한다. 서울에 주소를 둔 26세의 한국인 남자가 1년간 사우디 아라비아에서 건설기능공으로 근무하고 1981년 9월 귀국하여 약 8개월 후인 1982년 5월 경부터 심한 피로감, 전신쇠약, 복부의 수물등을 느끼기 시작하였다. 환자가 국립서울병원을 거쳐 서울대학교병원에 1982년 9월 17일 입원할 당시에는 간과 비장이 모두 14cm정도 만져질 만큼 부어있었고, 심한 체중 감소(4개월간 14kg의 감소), 적혈구, 백혈구, 혈소판등 모든 혈구의 감소등이 관찰되었다. 간생검을 통해 amastigote가 관찰되고 이는 투사전자현미경을 통해서 전형적인 amastigote형으로 확인되었다. 환자는 국외에서 구한 약제인 sodium antimony gluconate(Pentostam )와 각종 보조요법에 의해 치료를 받았다. 퇴원 직전에 시행한 간생검에서 괴사된 간 조직이 섬유화로 대치된 것이 확인되었고 충체는 관찰되지 않았다. 이 Kala-azar 에는 1952년 만주에 유입되어 보고된 3예 이후로는 처음 관찰된 것으로 중동에서 유입된 것으로는 첫번째 보고례이다. 최근 급격히 늘어난 해외 인력진출을 감안하면 해당 지역의 열대 풍토병에 대한 다각적인 대책이 절실히 요청된다.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.270-274
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• 2010

Purpose: Here we present tardy ulnar nerve palsy cases that were caused by the anconeus epitroch-learis muscle. Materials and Methods: A 37 year old female patient presented with tardy ulnar nerve palsy findings for the elbow. During surgery, an atypical anconeus epitrochlearis muscle was observed, which originated from the triceps aponeurosis and inserted into the medial intermuscular septum. Muscle resection, nerve decompression and ulnar nerve anterior transposition were done. A 35 year old male patient presented with tardy ulnar nerve palsy findings for the elbow. During surgery, a typical anconeus epitrochlearis muscle was found. Muscle resection, nerve decompression and ulnar nerve anterior transposition were done. Results and Conclusion: Tardy ulnar nerve palsy can be associated with and caused by either an atypical or a typical anconeus epitrochlearis muscle.

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.38-45
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• 1996

Background: Diagnosis of subpulmonary effusion is thought to be somewhat difficult more than pulmonary effusion. Clinical course and pathophysiology are thought to be different from typical pulmonary effusion. This study was done for increasing high suspicious index and early diagnosis of subpulmonary effusion. Method: Among the patients at dept. of chest medicine, National Medical Center from January 1990 to Dec. 1993, 232 cases of typical pulmonary effusion and 42 cases of subpulmonary effusion were studied. Result: 1) The ratio of subpulmonary effusion and typical pulmonary effusion was about 1:5. 2) Male to Female ratio was 1:1 in both effusion. 3) Rt. side pleural and subpleural effusion were slightly predominant. 4) Subjective symptoms are chest pain, cough and exertional dyspnea. There is no difference between subpulmonary and typical pulmonary effusion. 5) Duration of symptom was slightly longer in subpulmonary effusion. 6) The most common cases of pleural effusion is tuberculosis in both subpulmonary & typical pulmonary effusion. Non-specific pleuritis was more common in subpulmonary effusion. 7) Pleural effusion was recurred about one fifth in both subpulmonary & pulmonary effusion. Conclusion: We studied clinical course and laboratory findings between subpulmonary & pulmonary effusion. However there are no definite difference between subpulmonary & pulmonary effusion. Duration of symptom was slightly longer in subpulmonary effusion. Most common cause was tuberculosis. Non specific pleuritis was more prevalent in subpulmonary effusion.

• Nuclear Engineering and Technology
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• v.23 no.3
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• pp.285-298
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• 1991

An example application of the fuzzy set theory is first made to a simple portion of a given accident progression event tree with typical qualitative fuzzy input data, and thereby computational algorithms suitable for application of the fuzzy set theory to the accident progression event tree analysis are identified and illustrated with example applications. Then the procedure used in the simple example is extended to extremely complex accident progression event trees with a number of phenomenological uncertainty issues, i.e., a typical plant damage state‘SEC’of the Zion Nuclear Power Plant risk assessment. The results show that the fuzzy averages of the fuzzy outcomes are very close to the mean values obtained by current methods. The main purpose of this paper is to provide a formal procedure for application of the fuzzy set theory to accident progression event trees with imprecise and qualitative branch probabilities and/or with a number of phenomenological uncertainty issues.