• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권5호
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• pp.1489-1515
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• 2022

The number of interconnected real-world devices such as sensors, actuators, and physical devices has increased with the advancement of technology. Due to this advancement, users face difficulties searching for the location of these devices, and the central issue is the findability of Things. In the WoT environment, keyword-based and geospatial searching approaches are used to locate these devices anywhere and on the web interface. A few static methods of indexing and ranking are discussed in the literature, but they are not suitable for finding devices dynamically. The authors have proposed a mechanism for dynamic and efficient searching of the devices in this paper. Indexing and ranking approaches can improve dynamic searching in different ways. The present paper has focused on indexing for improving dynamic searching and has indexed the Things Description in Solr. This paper presents the Things Description according to the model of W3C JSON-LD along with the open-access APIs. Search efficiency can be analyzed with query response timings, and the accuracy of response timings is critical for search results. Therefore, in this paper, the authors have evaluated their approach by analyzing the search query response timings and the accuracy of their search results. This study utilized different indexing approaches such as key-words-based, spatial, and hybrid. Results indicate that response time and accuracy are better with the hybrid approach than with keyword-based and spatial indexing approaches.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.496-500
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• 2015

International construction projects are inherently more risky than domestic projects with multi-dimensional uncertainties that require complementary risk management at both the country and project levels. However, despite a growing need for systematic country evaluations, most studies have focused on project-level decisions and lack country-based approaches for firms in the construction industry. Accordingly, this study suggests data-driven approaches for evaluating countries using two quantitative models. The first is a two-stage country segmentation model that not only screens negative countries based on country attractiveness (macro-segmentation) but also identifies promising countries based on the level of past project performance in a given country (micro-segmentation). The second is a multi-criteria country segmentation model that combines a firm's business objective with the country evaluation process based on Kraljic's matrix and fuzzy preference relations (FPR). These models utilize not only secondary data from internationally reputable institutions but also performance data on Korean firms from 1990 to 2014 to evaluate 29 countries. The proposed approaches enable firms to enhance their decision-making capacity for evaluating and selecting countries at the early stage of corporate strategy development.

• Korean Journal of Radiology
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• 제22권10호
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• pp.1697-1707
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• 2021

The recent introduction of various high-dimensional modeling methods, such as radiomics and deep learning, has created a much greater diversity in modeling approaches for survival prediction (or, more generally, time-to-event prediction). The newness of the recent modeling approaches and unfamiliarity with the model outputs may confuse some researchers and practitioners about the evaluation of the performance of such models. Methodological literacy to critically appraise the performance evaluation of the models and, ideally, the ability to conduct such an evaluation would be needed for those who want to develop models or apply them in practice. This article intends to provide intuitive, conceptual, and practical explanations of the statistical methods for evaluating the performance of survival prediction models with minimal usage of mathematical descriptions. It covers from conventional to deep learning methods, and emphasis has been placed on recent modeling approaches. This review article includes straightforward explanations of C indices (Harrell's C index, etc.), time-dependent receiver operating characteristic curve analysis, calibration plot, other methods for evaluating the calibration performance, and Brier score.

• Earthquakes and Structures
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• 제26권5호
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• pp.363-382
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• 2024

In India's north-eastern region, low-strength autoclaved aerated concrete (AAC) blocks are widely used for constructing masonry structures, making them susceptible to lateral forces due to their low tensile and shear strengths and brittleness nature. The absence of earthquake-resistant attributes further compromises their resilience during seismic events. An economically viable solution to enhance the structural integrity of these masonry structures involves integrating steel wire mesh within the masonry mortar joints. This study investigates the in-plane shear behaviour of AAC masonry by employing two approaches: incorporating steel wire mesh within the masonry bed joint "BJ" and the masonry bed and head joint "BHJ". These approaches aim to augment strength and ductility, potentially serving as earthquake-resistant attributes in masonry structures. Three distinct variations of steel wire mesh and three reinforcing arrangements, i.e. (-), (L) and (Z) arrangement were employed to reinforce the two approaches. The test result reveals a significant enhancement in structural performance upon inclusion of steel wire mesh in both reinforcing approaches, with the "BHJ" approach outperforming the "BJ" approach and the unreinforced masonry, along with increase in capacity as the wire mesh size increases. Furthermore, the effectiveness of the reinforcing arrangement is ranked with the (Z) arrangement showing the largest performance, followed by the (L) and (-) arrangement.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2024년도 춘계학술발표대회
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• pp.53-56
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• 2024

Though lots of approaches to develop mobile apps are suggested up to now, developers have difficulties selecting a right one. This study compares native and cross-platform application development approaches, particularly focusing on the shift in preference from Java to Kotlin and the increasing use of Flutter. This research offers practical insights into factors influencing developers' choice of programming languages and frameworks in mobile application development by creating identical applications using Java, Kotlin, and Dart (Flutter). Furthermore, this study explores the best practices for development by examining the quality of code in 45 open-source GitHub repositories. The study evaluates LOC and code smells using semi-automated SonarQube assessments to determine the effects of selecting a specific language or framework on code maintainability and development efficiency. Preliminary findings show differences in the quality of the code produced by the two approaches, offering developers useful information on how to best optimize language and framework selection to reduce code smells and improve project maintainability.

• 보건교육건강증진학회지
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• 제28권2호
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• pp.1-13
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• 2011

Objectives: This study investigated beliefs of Koreans on the usefulness of various resources they use to alleviate depressive symptoms and to identify factors affecting the beliefs on different approaches to depressive symptoms. Methods: A household survey was conducted on a stratified sample of adults of age 18~74 (N=1,607) in 2009. The participants were asked to read a case vignette of depression and to provide their opinion about usefulness of 39 types of resources as ways of addressing the symptoms. Factors affecting opinions on usefulness of various resources were examined with logistic regression. Results: The three approaches identified via factor analysis were believed to be useful in the order of 'psychological/relational/activity-oriented', 'lifestyle/cultural', and 'physical/medical' approaches. The logistic regression analyses revealed that correct recognition of symptoms increased the likelihood of positive opinion about psychological and physical approaches, and so did having current symptoms about physical and popular approaches. Past help-seeking experience increased the likelihood of negative opinion about physical approach, however. Conclusions: Strategies to adopt various types of resources need to be developed, including rigorous use of psychosocial methods, mechanisms to control service quality, and the integration of diverse resources into the current community mental health services.

• 한국전산유체공학회지
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• 제20권3호
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• pp.79-86
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• 2015

A blood pump is an important part of a cardiac assist device. Since the shear rate in blood is known to be a primary factor on hemolysis generation, it has been very important to evaluate hemolysis inside blood pumps for understanding performance and reliability of cardiac assist devices. In this study, hemolysis generation inside blood pumps is analyzed using CFD with power-law based models for the blood damage index(BDI), in order to overcome difficulties in measuring hemolysis by experiment. The BDI values in blood pumps can be evaluated using Lagrangian or Eulerian approaches. In this study, several Lagrangian and Eulerian approaches are compared to estimate the efficiency of the numerical methods in a practice sense. It is found that the Eulerian approaches are advantageous in terms of the efficiency and robustness. Two different Eulerian approaches are used to evaluate the BDI values of a few commercial blood pumps. For the conditions of extracorporeal membrane oxygenator(ECMO) and ventricular assist device(VAD), local generation of hemolysis is analyzed using divided regions of blood pumps, in order to investigate the effects of the pump geometry.

• Journal of Korean Neurosurgical Society
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• 제29권1호
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• pp.44-50
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• 2000

Objective : A few anecdotal cases of mesenchyme-derived tumors which grow into a cranial cavity have been reported that disclosed a dismal prognosis, due to their critical location, aggressive biological behavior, and high rate of surgical morbidity. The aim of this study is to search clinical factors related to these tumors. Methods : Eight patients who underwent surgical removal of intracranial mesenchymal tumors between January 1993 and December 1997 were studied retrospectively. The tumors included are three chordomas, two chondrosarcomas, two rhabdomyosarcomas, and one hemangiopericytoma. Authors compared clinical features, treatment, and results of our cases with reported cases. The mean follow-up period was 20.5 months. Results : All cases showed nonspecific, location-related clinical findings and arose from sphenopetroclival region. Single stage operation was performed in 4 cases, and skull base approaches in 3 cases. Adjuvant therapies were done in 2 cases. Recurrence was seen in 3 cases(37.5%), and 3 patients died. Interdisciplinary approach with otologic surgeon was done in 2 cases. Conclusion : Recent advancement of refined tactics has made these tumors amenable and provides prolongation of progression-free survival. These are modified skull base approaches, multi-modality treatment options, and inter-disciplinary team approaches. Good results may be expected for these mesenchymal tumors by aggressive resection and adjuvant therapies according to their biological nature.

• 한국학교ㆍ지역보건교육학회지
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• 제7권
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• pp.19-32
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• 2006

성공적이고 효과적인 학교 성교육을 위하여 참여형 기법의 중요성이 부각되고 있는 가운데, 지역사회 참여형 연구 기법이 주목받고 있다. 지역사회 참여형 기법은 피교육자가 교육프로그램의 기획, 수행, 평가 전 과정에 동등한 협력자로서 적극적으로 참여할 수 있도록 여건을 구비하고 제공하는 것이 그 목적이자 방법이다. 사회생태학 모델은 이러한 참여형 기법을 적용할 때 유용한 도구로서, 사전조사 및 교육 프로그램 기획 뿐 아니라 평가도구로서의 가능성도 가지고 있다. 학교 성교육의 과제 중 하나인 교육요구와 실제 간의 간극 해소를 위한 시도의 일환으로, 본 논문은 지역사회 참여형 연구의 주요 개념과 원칙, 사회생태학 모델의 원리를 설명하고, 실제 학교 성교육 평가 사례에 입각한 사회생태학 모델의 용례를 제시하였다. 아울러, 학교 성교육 현장에서 프로그램 기획 및 평가에 참여형 기법을 통하여 사회생태학 모델을 적용하는 방안을 논의하였다.

• Journal of Korean Neurosurgical Society
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• 제44권1호
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• pp.1-7
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• 2008

Objective : The purpose of this study was to investigate the factors affecting the surgical outcome and to compare the surgical results between transsylvian and transcortical approaches in patients with putaminal hematomas. Methods : Retrospective review of charts and CT scan images was conducted in 45 patients (20 transsylvian and 25 transcortical approaches) who underwent open surgical evacuation of putaminal hematomas. Mean Glasgow coma scale (GCS) score and hematoma volume were $7.5{\pm}3.2$ and $78.1{\pm}29.3\;cc$, respectively. The factors affecting the functional mortality were investigated using a multivariate logistic regression analysis. In addition, surgical results between transsylvian and transcortical approaches were compared. Results : None of the patients had a good recovery after the surgery. Overall functional survival rate and mortality were 37.7% and 31%, respectively. The only risk factor for functional mortality was GCS motor score after controlling age, history of hypertension, side of hematoma, hematoma amount midline shift, presence of intraventricular hemorrhage and surgical approach (p=0.005). Even though a transcortical approach was shorter in operative time (4.4 versus 5.1 hour) and showed a higher mortality rate (40% versus 20%) and lower functional survival (45% versus 35%) compared to the transsylvian approach, the differences were not statistically significant between the two groups. Conclusion : In patients who have large amounts of hematoma and require open surgical evacuation, the only significant risk factor for functional survival is the preoperative GCS score. Cortical incision methods such as transsylvian and transcortical approaches have no influence on the surgical outcome. To decompress the swollen brain rapidly, transcortical approach seems to be more suitable than transsylvian approach.