• Korean Journal of Radiology
• /
• 제24권2호
• /
• pp.155-165
• /
• 2023

Objective: Little is known about the effects of using different expert-determined reference standards when evaluating the performance of deep learning-based automatic detection (DLAD) models and their added value to radiologists. We assessed the concordance of expert-determined standards with a clinical gold standard (herein, pathological confirmation) and the effects of different expert-determined reference standards on the estimates of radiologists' diagnostic performance to detect malignant pulmonary nodules on chest radiographs with and without the assistance of a DLAD model. Materials and Methods: This study included chest radiographs from 50 patients with pathologically proven lung cancer and 50 controls. Five expert-determined standards were constructed using the interpretations of 10 experts: individual judgment by the most experienced expert, majority vote, consensus judgments of two and three experts, and a latent class analysis (LCA) model. In separate reader tests, additional 10 radiologists independently interpreted the radiographs and then assisted with the DLAD model. Their diagnostic performance was estimated using the clinical gold standard and various expert-determined standards as the reference standard, and the results were compared using the t test with Bonferroni correction. Results: The LCA model (sensitivity, 72.6%; specificity, 100%) was most similar to the clinical gold standard. When expert-determined standards were used, the sensitivities of radiologists and DLAD model alone were overestimated, and their specificities were underestimated (all p-values < 0.05). DLAD assistance diminished the overestimation of sensitivity but exaggerated the underestimation of specificity (all p-values < 0.001). The DLAD model improved sensitivity and specificity to a greater extent when using the clinical gold standard than when using the expert-determined standards (all p-values < 0.001), except for sensitivity with the LCA model (p = 0.094). Conclusion: The LCA model was most similar to the clinical gold standard for malignant pulmonary nodule detection on chest radiographs. Expert-determined standards caused bias in measuring the diagnostic performance of the artificial intelligence model.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
• /
• pp.87-90
• /
• 2004

Telematics is an emerging industrial field made up of the convergence of technologies. The key technologies for Telematics are server-side technology, terminal-side technology, communication-related technology, and positioning technology. Standardization in Telematics is now getting more notice these days. Domestic situation is explained for several related facilities such as ETRI, TTA, and Telematics Standardization Forum. In this paper, we will focus especially on the standard reference model that is the most fundamental framework of Telematics technology standardization. In the reference model, the Telematics system is composed of Telematics client part, communication part, and Telematics server part. The Telematics client part consists of terminal, positioning device, and car electronic devices. Communication part can be composed of various telecommunication channels such as CDMA, WLAN, DMB, WiBro, etc. which can guarantee the seamless two-way communication. Telematics server part is composed of TSP(Telematics Service Provider) server and CP(Contents Provider) servers gathering and managing the various Telematics services. This Telematics reference model is expected to be utilized as the base architecture in developing the technology and standards from now on.

• 한국전자거래학회지
• /
• 제1권1호
• /
• pp.159-171
• /
• 1996

Nowadays, multimedia and Hypermedia become hot topics in information industry. Due to high capacity of media storage and fast communication network, it is possible to exchange text data as well as image, moving picture and voice. Especially to apply hypermedia under CALS standard environment, the relation between international standard and CALS standard needs to be considered. This study introduces conceptual background and processing model of HyTime (Hypermedia Time-based Structuring Language) which is a specification of hypermedia exchange, Hyper ODA (Hyper Open Document Architecture) which is a major multimedia communication basis, MMCF (Multimedia Communication Forum), AHM(Amsterdam Hypermedia Model), and DSRM(DAVIC System Reference Model) reference model which helps determination of hypermedia communication specification Although they are international standard, provisional standard or non-standard, it discusses the Possibility of adopting them as CALS standard. Hence, this paper chooses the best recommend for CALS among these models.

• 정보처리학회논문지D
• /
• 제12D권5호
• /
• pp.729-736
• /
• 2005

현재 국방부에서는 국방정보체계간 상호운용성을 보장하기 위해 아키텍처산출물을 쉽고 일관성이 있게 개발할 수 있는 국방아키텍처프레임워크와 개발된 아키텍처산출물을 저장하는 핵심아키텍처데이터모델을 개발하였다. 국방아키텍처프레임워크에 정의된 기술참조모델과 표준프로파일 산출물은 정보기술아키텍처의 핵심 부분이며 상호운용성 보장의 핵심 요소이다. 본 논문에서는 기술참조모델과 표준프로파일의 기술서비스와 표준을 관리하는 알고리즘과 시스템을 개발하였다. 이를 통해 기술참조모델과 표준프로파일 산출물의 효율적인 작성 및 관리와 정보체계간의 상호운용성 보장의 기반을 제공할 수 있다.

• 한국컴퓨터정보학회논문지
• /
• 제17권8호
• /
• pp.71-80
• /
• 2012

최근 클라우드 컴퓨팅을 위한 많은 표준화 연구가 진행되어 왔으나 데이터 공유 및 교환을 위한 표준 연구는 거의 이루어지지 않았다. 무엇보다 해당 표준화 기구에서는 의미 상호운용성 향상을 위한 구체적인 표준화 항목 및 참조 모델을 제시하고 있지 않다. 이 논문에서는 현재까지의 표준화 문제점을 정의하고, 의미 상호운용성 제공을 위한 구체적인 표준화 항목 및 참조 모델을 제안한다. 이를 위해 먼저 클라우드 컴퓨팅을 위한 전반적인 표준화 동향을 분석하고, 특히 데이터의 의미적 상호운용성을 제공을 위한 표준 개발 현황을 기술한다. 또한 다양한 분야의 표준개발에 이용된 데이터 교환 및 관리 분야의 표준 개념을 기반으로 잠재적인 표준화 항목을 정의한다. 마지막으로, 표준화 항목 간의관계성과 전체적인 의미 상호운용성 과정을 보여주기 위해 참조 모델을 기술한다. 이 논문은 표준 개발을 위한 가이드라인으로서 이용될 수 있으며, 아울러 클라우드 컴퓨팅의 표준화를 촉진할 수 있다.

• International Journal of Control, Automation, and Systems
• /
• 제4권1호
• /
• pp.70-76
• /
• 2006

The objective of this paper is to propose a reference model of a fire detection and monitoring system using MS/TP protocol. The reference model is designed to satisfy the requirements of response time and flexibility. The reference model is operated on the basis of BACnet, a standard communication protocol for building automation systems. Validity of the reference model was examined using a simulation model. This study also evaluated the performance of the BACnet-based fire detection and monitoring system in terms of network-induced delay. Simulation results show that the reference model satisfies the requirements of the fire detection and monitoring system.

• 신재생에너지
• /
• 제20권1호
• /
• pp.95-101
• /
• 2024

Since 1990, the Renewable Big Data Research Lab at the Korea Institute of Energy Technology has been observing solar radiation at 16 sites across South Korea. Serving as the National Reference Standard Data Center for Renewable Energy since 2012, it produces essential data for the sector. By 2020, it standardized meteorological year data from 22 sites. Despite user demand for data from approximately 260 sites, equivalent to South Korea's municipalities, this need exceeds the capability of measurement-based data. In response, our team developed a method to derive solar radiation data from satellite images, covering South Korea in 400,000 grids of 500 m × 500 m each. Utilizing satellite-derived data and ERA5-Land reanalysis data from the European Centre for Medium-Range Weather Forecasts (ECMWF), we produced standard meteorological year data for 1,000 sites. Our research also focused on data measurement traceability and uncertainty estimation, ensuring the reliability of our model data and the traceability of existing measurement-based data.

• Korean Journal of Radiology
• /
• 제22권12호
• /
• pp.2017-2025
• /
• 2021

Objective: To evaluate the accuracy and clinical efficacy of a hybrid Greulich-Pyle (GP) and modified Tanner-Whitehouse (TW) artificial intelligence (AI) model for bone age assessment. Materials and Methods: A deep learning-based model was trained on an open dataset of multiple ethnicities. A total of 102 hand radiographs (51 male and 51 female; mean age ± standard deviation = 10.95 ± 2.37 years) from a single institution were selected for external validation. Three human experts performed bone age assessments based on the GP atlas to develop a reference standard. Two study radiologists performed bone age assessments with and without AI model assistance in two separate sessions, for which the reading time was recorded. The performance of the AI software was assessed by comparing the mean absolute difference between the AI-calculated bone age and the reference standard. The reading time was compared between reading with and without AI using a paired t test. Furthermore, the reliability between the two study radiologists' bone age assessments was assessed using intraclass correlation coefficients (ICCs), and the results were compared between reading with and without AI. Results: The bone ages assessed by the experts and the AI model were not significantly different (11.39 ± 2.74 years and 11.35 ± 2.76 years, respectively, p = 0.31). The mean absolute difference was 0.39 years (95% confidence interval, 0.33-0.45 years) between the automated AI assessment and the reference standard. The mean reading time of the two study radiologists was reduced from 54.29 to 35.37 seconds with AI model assistance (p < 0.001). The ICC of the two study radiologists slightly increased with AI model assistance (from 0.945 to 0.990). Conclusion: The proposed AI model was accurate for assessing bone age. Furthermore, this model appeared to enhance the clinical efficacy by reducing the reading time and improving the inter-observer reliability.

• 한국IT서비스학회지
• /
• 제5권1호
• /
• pp.111-128
• /
• 2006

It was on the rise importantly to provide the efficient management process of the organization for dealing with the change about information and business management quickly and consistently. It was suggested with the architectural model on information technology to provide it in theoretically. The Federal Government and budget organization of the USA used it on actual business and the terms of EA (Enterprise Architecture) and are raising the efficiency of management. NCA (National Computerization Agency) of Korea published the book - "The Research about establishing ITA (Information Technology Architecture) and appling the standards". After being applied the model on MOGAHA (Ministry of Government Administration and Home Affairs) and MIC(Minisstry of Information and Communication), the concrete case was made. MOMAF (Ministry of Maritime Affairs and Fisheries) drove the leading model. The report ascertained the basic contents of ITA and researched the case of USA, MOGAHA, MIC, and tried to analyze the contents of appling maritime and fisheries area. The report contained the definition of purpose through analyzing environment and establishing the vision and the principles based on them. The report also contained the contents of architecture based on the standard of NCA - "The Government Standard Meta Model version 2.0" - and researched the MOMAF's Reference model using Government Reference model. The report established the investment architecture and the process of information technology asset management. It ascertained the characteristic of maritime & fisheries area and the subject of developing the MOMAF's ITA sustainably.

• 대한전기학회논문지:시스템및제어부문D
• /
• 제49권3호
• /
• pp.102-110
• /
• 2000

In this paper, Wiener-Hopf design of the two-degree-of-freedom(2DOF) controller configuration is treated for the standard plant model. It is shown that the 2DOF structure makes it possible to treat the design of feedback properties and reference tracking problem separately. Wiener-Hopf factorization technique is used to obtain the optimal controller which minimizes a given quadratic cost index. The class of all stabilizing controllers that yield finite cost index is also characterized. An illustrative example is given for the step reference tracking problem which can not be treated by the conventional H2 controller formula.