• Journal of Information Processing Systems
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• 제20권3호
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• pp.317-327
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• 2024

Along with the rapid development of the database technology, as well as the widespread application of the database management systems are more and more large. Now the data mining technology has already been applied in scientific research, financial investment, market marketing, insurance and medical health and so on, and obtains widespread application. We discuss data mining technology and analyze the questions of it. Therefore, the research in a new data mining method has important significance. Some literatures did not consider the differences between attributes, leading to redundancy when constructing concept lattices. The paper proposes a new method of uncertain data mining based on the concept lattice of connotation difference degree (c_diff). The method defines the two rules. The construction of a concept lattice can be accelerated by excluding attributes with poor discriminative power from the process. There is also a new technique of calculating c_diff, which does not scan the full database on each layer, therefore reducing the number of database scans. The experimental outcomes present that the proposed method can save considerable time and improve the accuracy of the data mining compared with U-Apriori algorithm.

• 한국산림과학회지
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• 제83권2호
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• pp.229-238
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• 1994

세계 여러지역에서 임목생장과 활력감소가 커다란 문제점으로 대두되고 있는 바, 이 논문은 북미, 유럽 그리고 동아시아에서 대기오염으로 인한 삼림피해에 관해 현재까지 알려진 바를 요약하고 있다. 오염원 주변에서의 삼림쇠퇴는 상당히 오랫동안 인지되어 왔으나, 오염원으로부터 먼거리에 이르기까지 광범위하게 피해를 준 경우는 그리 흔치 않다. 북미지역의 경우, Los Angeles와 Mexico City 주변에서 고농도의 오존으로 인해 삼림쇠퇴가 일어나고 있고, 미국 동부의 고산지대에서는 강산성의 안개에 의한 가문비나무의 내동성 감소로 피해가 있음이 밝혀지고 있다. 유럽의 경우 독일가문비나무가 Mg 결핍과 N 과다공급이 원인이 되어 피해를 입고 있는 것으로 보이며, 지역적으로 삼림쇠퇴현상이 보이기는 하지만 전체적인 임분생장량이나 현존 biomass가 1970년에 비해 1990년에 증가되었다. 동아시아의 경우, 이에 관한 연구가 초기단계에 있는 바, 중국의 여러 공업지대에서 강산성 강우현상을 보이고 삼림쇠퇴의 주원인이 대기오염일 것으로 사료되는 예가 보고되고 있으며, 한국의 대도시와 공단주변에서 대기오염에 의한 삼림피해 현상을 보이고 있다. 전체적으로 볼 때 온대림에서 광범위한 삼림쇠퇴 현상은 보이지 않고 있으며, 지역별로 상이하게 나타나는 삼림쇠퇴의 정확한 원인을 밝혀내기 쉽지 않다. 대면적에 걸쳐 나타날 수 있는 삼림피해에 대비하는 계속적인 감시와 연구가 앞으로의 과제로 남아있다.

• 대한지리학회지
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• 제33권3호
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• pp.447-454
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• 1998

24,000에서 25,000년 전 무렵 일본 구주의 아이라화산에서 분출한 아이라Tn화산재. 즉 AT는 동북아시아 플라이스토세 말의 중요한 층준이 되는 광역화산재이다. AT는 색상과 형태에 있어서의 특징, 특히 소위 bubble-wall구조라 불리는 형태적 특징에서 쉽게 확인할 수 있으며, 한국에서는 1983년 처음 발견되었다. 전국각지의 구석기퇴적층에 대한 조사 결과 모두 7 지점에서 AT를 발견할 수 있었다. 이러한 발견과 더불어, 몇몇 저명한 플라이스토세 퇴적층의 연대와 기원은 재고되어야 한다고 보인다. 널리 알려진 구석기유적인 전곡리에서의 AT 발견은 어째서 다른 지역에서는 이미 오래 전에 사라진 유물이 이곳에서는 플라이스토세 말기까지 계속 만들어졌는가 하는 새로운 질문을 던져 주고 있다. 또한, 동해안 정동진 남쪽 일대에 발달한 해안단구의 상부퇴적층에서도 AT가 발견되었다. 이곳의 해안단구는 플라이스토세 전기 초에 해수면변화로 형성된 지형이라고 여겨지고 있기 때문에 이러한 발견은 매우 충격적이라 할 만하다. 이러한 발견례들은 한반도 제4기 층서의 이해를 위한 새로운 틀이 필요하며 나아가 제4기와 관계된 여러 분야의 연구에서 광역화산재에 대한 고려가 필요함을 보여준다.

• 한국도서관정보학회지
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• 제31권1호
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• pp.63-86
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• 2000

This essay traces the paths in which the writers have involved themselves in developing 'the studies of the present developmental stage' in their own field of studies, an by extension have become aware of the widespread presence of the discussion of decolonization in fields of social sciences. The present essay takes communication studies for a case of an indepth analysis of the effort toward academic self-reliance.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제3권2호
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• pp.5-16
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• 1999

We introduce a new projector for accelerating convergence of a symmetric eigenvalue problem Ax = x, and devise a power/Lanczos hybrid algorithm. Acceleration can be achieved by removing the hard-to-annihilate nonsolution eigencomponents corresponding to the widespread eigenvalues with modulus close to 1, by estimating them accurately using the Lanczos method. However, the additional Lanczos results can be obtained without expensive matrix-vector multiplications but a very small amount of extra work, by utilizing simple power-Lanczos interconversion algorithms suggested. Numerical experiments are given at the end.

• Journal of Chest Surgery
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• 제17권1호
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• pp.89-93
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• 1984

These two pulmonary actinomycosis cases had undergone right upper lobectomy and left lower lobectomy individually under the diagnosis of lung cancer and lung abscess. Recently pulmonary actinomycosis is very rare by the widespread use of antibiotics. In addition to clinical similarity to lung cancer and pulmonary tuberculosis, lack of suspicion and difficulty in obtaining adequate culture material also hamper the precise preoperative diagnosis. The purpose of this report is to review of our experiences and to enhance consideration of pulmonary actinomycosis.

• Journal of Chest Surgery
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• 제24권5호
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• pp.480-484
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• 1991

Traumatic rupture of the main bronchus is comparatively very rare. With the advent of widespread mechanization and high-speed era, the incidence of traumatic rupture of the tracheobronchial tree has been increased considerably. Rupture of the bronchus is an unusual result of nonpenetrating trauma to the chest. Early recognition of bronchial rupture and emergency thoracotomy and management is essential for reducing of morbidity, mortality and late complications. We experienced 3 cases of bronchial rupture caused by nonpenetrating chest trauma with or without rib fracture. Patients were suffered from dyspnea and chest pain. After closed thoracostomy, corrective surgery was performed. Postoperative courses were uneventful and discharged without any complication.

• 한국문헌정보학회지
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• 제20권
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• pp.297-330
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• 1991

The work presents the theoretical background and methodology to network analysis. This approach to information network has been widespread use in many researches of social science. Theoretically based idea of structural analysis of information flow were reviewed and the major perspective and the practical aspects of the analysis were discussed. To show an approach of the methodology to library environment, HISP project which analyzed the network structure of a health information dissemination to a health community was demonstrated.

• 산업공학
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• 제13권3호
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• pp.288-295
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• 2000

As the industrial environment becomes more competitive, supply chain management(SCM) has become recognized as a major strategy in the business world. Despite its current widespread popularity, its basic concepts are confused with those of other exiting logistic tools and not clearly understood. This paper introduces the current status of SCM in terms of physical logistics, interrelationship with other logistic tools as well as the general history and definitions of SCM. Researches are categorized into deterministic models, stochastic models, simulation models, and several future research areas are discussed in this paper.

• Journal of information and communication convergence engineering
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• 제8권1호
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• pp.116-121
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• 2010

New teaching and studying methods using educational contents are gradually widespread with the advancement of information and communication technology. As educational contents, in this paper, we design and implement linguistic contents for studying essential expressions applied to various situations of real life. In detail, the linguistic contents are run on web environments, and have suitable animations for learning essential expressions based on several foreign languages in contextual dialogues. Also, useful functions are included in contents to reinforce what users have learned.