• 전자공학회논문지SC
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• 제47권4호
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• pp.7-14
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• 2010

유한 상태 머신으로 표현되는 비동기 머신의 안정 상태 동작은 피드백 제어를 통해서 원하는 목적에 맞게 교정될 수 있다. 본 논문에서는 불확실한 상태 천이를 가지는 입력/상태 비동기 머신을 위한 상태 피드백 제어기를 제안한다. 비동기 머신은 결정적인 동작 특성을 가지고 있으나 모델 불확실성, 내부 고장 등으로 인해서 일부 영역의 상태 천이 함수가 불확실하다. 교정 제어의 목적은 불확실한 상태 천이를 고려하면서 머신의 폐루프 동작이 주어진 정상적인 모델 동작의 부분 집합이 되도록하는 일이다. 또 제어기는 실제 교정 동작을 수행하면서 획득하는 머신의 정확한 상태 천이를 그 다음 제어 동작에 반영한다. 즉 학습을 통해서 폐루프 시스템이 이룰 수 있는 모델의 부분 동작의 범위가 더 확대된다. 사례 연구를 제안된 제어기의 설계 과정을 예시한다.

• Communications for Statistical Applications and Methods
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• 제20권6호
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• pp.455-466
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• 2013

In nested case-control studies, the most common way to make inference under a proportional hazards model is the conditional logistic approach of Thomas (1977). Inclusion probability methods are more efficient than the conditional logistic approach of Thomas; however, the epidemiology research community has not accepted the methods as a replacement of the Thomas' method. This paper promotes the inverse probability weighting method originally proposed by Samuelsen (1997) in combination with an approximate jackknife standard error that can be easily computed using existing software. Simulation studies demonstrate that this approach yields valid type 1 errors and greater powers than the conditional logistic approach in nested case-control designs across various sample sizes and magnitudes of the hazard ratios. A generalization of the method is also made to incorporate additional matching and the stratified Cox model. The proposed method is illustrated with data from a cohort of children with Wilm's tumor to study the association between histological signatures and relapses.

• Journal of Information Science Theory and Practice
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• 제7권3호
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• pp.21-30
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• 2019

Information about the formation and filling (in 2014 to 2016) of a terminological dictionary on electronics and radioengineering and collective work (in 2017 to 2018) with a data bank "TERMIN" is presented in this article. In purpose of creating an instrument of navigating the modern scientific-technical space a net of terms with set semantic links is described. This set is based on the analysis of terms' definitions (each term is checked for inclusion in the definitions of all other terms; the definitions were borrowed from reputable reference editions: encyclopedias, dictionaries, reference books). The created model of a system that consists of different information sources, in which it (information) is indexed by the terminology of Russian State Rubricator of Scientific and Technical Information rubrics and/or keywords, is described. There is an access for the search in all these sources in the system. Searching inquiries are referred to in the language of these rubrics or formulated by arbitrary terms. The system is to refer to information sources and give out relevant information. In accordance with this model, semantic links of various types, which allow expanding a search at different modalities of query, should be set among data bank terms. Obtained links will have to increase semantic matching, i.e., they can provide actual understanding of the meaning of the information that is being sought.

• Korean Journal of Geomatics
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• 제2권2호
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• pp.131-137
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• 2002

The digital photogrammetric products have been increasingly used as an accurate foundation for representing information associated with infrastructure management. The technological advances in merging raster and vector data within the framework of GIS have allowed for the inclusion of DTMs and digital orthophotos with vector data and its associated attributes. This study addresses not only generating DEMs and digital orthophotos but producing three dimensional building models from aerial photos of an urban area by employing the digital photogrammetric technology. DEMs and digital orthophotos were automatically generated through the process of orientations, image matching and so on, and then the practical problems, which must be solved especially in applying to urban areas, were considered. The accuracy of produced digital orthophotos was derived by using check points. Also three dimensional visualization imagery, which is useful in the landform analysis, and 3D building models were produced. Digital photogrammetric products would be used widely not only as GIS framework data layers by using the GIS link function which links attribute and image information in the database for applying to infrastructure management and but as geospatial data for especially 3D GIS in urban areas.

• Coupled systems mechanics
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• 제8권1호
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• pp.71-93
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• 2019

Finite element simulations of solid mechanics problems often involve the use of Non-Confirming Meshes (NCM) to increase accuracy in capturing nonlinear behavior, including damage and plasticity, in part of a solid domain without an undue increase in computational costs. In the presence of material nonlinearity and plasticity, higher-order variables are often needed to capture nonlinear behavior and material history on non-conforming interfaces. The most popular formulations for coupling non-conforming meshes are dual methods that involve the interpolation of a traction field on the interface. These methods are subject to the Ladyzhenskaya-Babuska-Brezzi (LBB) stability condition, and are therefore limited in their implementation with the higher-order elements needed to capture nonlinear material behavior. Alternatively, the enriched discontinuous Galerkin approach (EDGA) (Haikal and Hjelmstad 2010) is a primal method that provides higher order kinematic fields on the interface, and in which interface tractions are computed from local finite element estimates, therefore facilitating its implementation with nonlinear material models. The inclusion of higher-order interface variables, however, presents the issue of preserving material history at integration points when a increase in integration order is needed. In this study, the enriched discontinuous Galerkin approach (EDGA) is extended to the case of small-deformation plasticity. An interface-driven Gauss-Kronrod integration rule is proposed to enable adaptive enrichment on the interface while preserving history-dependent material data at existing integration points. The method is implemented using classical J2 plasticity theory as well as the pressure-dependent Drucker-Prager material model. We show that an efficient treatment of interface variables can improve algorithmic performance and provide a consistent approach for coupling non-conforming meshes in inelasticity.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1373-1377
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• 2016

Background: We vigorously reviewed patients' operation record who had adhesion of the Denonvilliers' fascia and found out most of these patients had prostatic bleeding after prostatic gland biopsies. We examined the magnitude of prostatic bleeding and frequency after biopsies and the relationship with oncological outcomes. Materials and Methods: A total of 285 patients were selected for the final analyses. Inclusion criteria were as follows: receiving MRI three weeks after biopsiesand laparoscopic radical prostatectomy within 300 days after biopsy. We divided the patients into two groups with (group A) or without (group B) prostatic bleeding. We examined the magnitude of prostatic bleeding after biopsies and the relationship with operation time (OT), positive surgical margin (PSM), biochemical recurrence (BCR) and other factors. Furthermore, we created a logistic-regression model to derive a propensity score for prostatic bleeding after biopsies, which included all patient and hospital characteristics as well as selected interaction terms, and we examined the relationship with PSM and BCR. Results: In all patients, the OT in the group B was shorter than the group A (p < 0.001). Prostatic bleeding was associated with PSM (p=0.000) and BCR (p=0.036). In this propensity-matched cohort, 11 of 116 patients in the group B had PSM as compared with 36 of 116 patients from group A (match-adjusted odds ratio, 4.30; 95%CI confidence interval, 2.06 to 8.96; P=0.000). In addition, eight of 116 patients in group B encountered BCR, as compared with 18 of 116 patients in group A (match-adjusted odds ratio, 2.48; 95%CI, 1.03 to 5.96; P=0.042). Kaplan-Meier analysis in the propensity matching cohort showed a significant biochemical recurrence-free survival advantage for being free of prostate bleeding after biopsies. Conclusions: Our findings in the present cohort should help equip surgeons to pay attention to careful excision especially for those who experienced deferred prostatic bleeding.