• Proceedings of the Korea Information Processing Society Conference
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• 2007.05a
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• pp.741-744
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• 2007

데스크탑 그리드 시스템에서 각 자원에서 수행한 작업 결과에 대한 정확성 검증은 중요한 문제이다. 작업 결과에 대한 정확성을 보장하기 위해서 결과 검증 기법으로 투표기반 기법이나 신뢰기반 기법이 사용되어 왔다. 그러나 이러한 기법들은 동적인 연산 환경에 효과적으로 대처하지 못하여 낮은 확장성과 높은 연산 지연을 초래할 수 있는 단점을 갖고 있다. 이러한 단점을 해결하고자 본 논문에서는 자원제공자에 의해 초래될 수 있는 잘못된 연산 결과에 대해 각 자원제공자의 신용도(credibility)를 동적으로 평가하여 연산 결과의 정확성을 판단하는 적응적 결과 검증 메커니즘(Adaptive Result Verification Mechanism: ARVM)을 제안한다. 또한, 제안하는 ARVM 은 자원제공자의 가용성(availability) 정보를 이용하여 결과 검증 시에 요구되는 연산 지연을 최소화한다.

• 제어로봇시스템학회:학술대회논문집
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• 1994.10a
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• pp.49-53
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• 1994

Advanced Real-Time Satellite Simulator(ARTSS) has been developed to support the telemetry, tracking and command operations of the ETRI satellite control system and to provide satellite engineers a more powerful and informative satellite simulations tool on the desktop. To provide extensive simulation functions for a communication satellite system in the pre-operational and operational missions, ARTSS uses a geosynchronous orbit(GEO) satellite model consisting of the attitude and orbit control subsystem, the power subsystem, the thermal subsystem, the telemetry, command and ranging subsystem, and the communications payload subsystem. In this paper, the system features and functions are presented and the satellite subsystem models are explained in detail.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.4
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• pp.90-97
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• 2014

Context-aware systems provide proper services for the user according to current contexts. However, it is not actively deployed in our daily lives as expected, due to many concerns including occurrences of exceptions. C++/C#/JAVA provide exception handling facilities for desktop computing programs, but context-aware system developers might feel far more difficult to make use of such general facilities, because it is hard to decide the timing and position of exception handling with various devices engaged. In this paper, we propose an exception detection and handling mechanism using device semantics and AspectJ so that it can constantly detect a large number of devices to allow the programmers to detect and handle exceptions with less burden.

• IEMEK Journal of Embedded Systems and Applications
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• v.10 no.3
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• pp.139-150
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• 2015

The major components of IoT(Internet of Things) environment are IoT devices rather than the conventional desktop computers. One of the intrinsic characteristics of IoT devices is diversity in view of data type and data access method. In addition, IoT devices usually deal with real-time data. In order to use such IoT data for internal business or cloud services, an IoT platform capable of easy domain management and consistent data access interface is required. This paper proposes a Linux FUSE-based virtual file system connecting IoT devices on POSIX file system view. It is possible to manage IoT domain with the native Linux utilities such as mkdir, mknod, ls and find in the file system. Also, the file system makes it possible to access or control IoT devices through POSIX interface such as open(), read(), write() or close() without any separate APIs or utilities. A test result shows that the management performance of the file system is lower than that of linux file system negligibly.

• 한국HCI학회:학술대회논문집
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• 2007.02a
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• pp.661-666
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• 2007

최근들어 제품을 개발하는 과정 중, 디자이너와 개발자, 의사 결정권자들이 FEM, CFD 시뮬레이션 결과를 리뷰할 때에 가상현실기술을 도입하는 사례가 늘고 있다. 몰입감을 높여주는 가상현실환경은 모델에 대한 해석 결과물을 정확하고 효과적으로 분석할 수 있도록 돕는다. 데이터의 실제 크기와 같게 혹은 그보다 더 크고 자세한 이미지를 제공하는 가상현실 몰입환경은 사용자가 데스크탑 환경만을 사용할 때 경험할 수 없는 높은 사실감을 제공함으로써 사용자에게 시각적인 만족감을 줄 수 있다. 하지만 데스크탑 환경에 비해 해상도가 낮고, 어두운 곳에서 스테레오 안경이나 HMD(Head Mounted Display), Data glove등을 착용해야 하는 불편함과 멀미, 시각적인 피로, 방향감각 상실로 대표되는 가상멀미 등으로 인해 장시간 사용에 어려움이 있다. 데스트탑 환경에서의 데이터 리뷰는 고해상도 이미지 분석은 가능하지만, 입체감이 떨어지기 때문에 리뷰 데이터의 실제감이 떨어진다. 이와 같은 문제점들을 보완하기 위해서 본 논문에서는 데스크탑 환경과 가상현실 환경 간의 협업이 가능한 FEM/CFD 가시화 시스템을 제시한다. 본 시스템은 가상현실 몰입환경에서 해석 데이터를 단순히 가시화하는 것뿐만이 아니라, 데스크탑 시스템과 동일한 3D 인터페이스 구조를 제공한다. 따라서, 해석 결과 분석을 위한 동일한 post-processing 작업이 네트워크로 연결된 원격 공간의 사용자들이 사용하는 시스템들 사이에서 실시간으로 진행될 수 있다.

• The Journal of Advanced Prosthodontics
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• v.10 no.3
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• pp.245-251
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• 2018

PURPOSE. To evaluate the accuracy of a model made using the computer-aided design/computer-aided manufacture (CAD/CAM) milling method and 3D printing method and to confirm its applicability as a work model for dental prosthesis production. MATERIALS AND METHODS. First, a natural tooth model (ANA-4, Frasaco, Germany) was scanned using an oral scanner. The obtained scan data were then used as a CAD reference model (CRM), to produce a total of 10 models each, either using the milling method or the 3D printing method. The 20 models were then scanned using a desktop scanner and the CAD test model was formed. The accuracy of the two groups was compared using dedicated software to calculate the root mean square (RMS) value after superimposing CRM and CAD test model (CTM). RESULTS. The RMS value ($152{\pm}52{\mu}m$) of the model manufactured by the milling method was significantly higher than the RMS value ($52{\pm}9{\mu}m$) of the model produced by the 3D printing method. CONCLUSION. The accuracy of the 3D printing method is superior to that of the milling method, but at present, both methods are limited in their application as a work model for prosthesis manufacture.

• Journal of Ocean Engineering and Technology
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• v.12 no.3 s.29
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• pp.86-95
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• 1998

CAD/CAM program developers have made substantial progress in enabling engineers to design, analyze, visualize, visualize, and simulate the performance of structures and systems. Many researchers, however, agree that there is still a way to go before the existing commercial computer software can be used in ship structural analysis to their full potential as solvers which can identify opportunities to reduce man-hours and cut costs. CAD systems used for these works in ship yards are general-purposed and not custom-tailored for ship structures, which force end-users to do tiresome and routine works. The new preprocessor "MeshGen" announced in this study can load several ship types and user-friendly generate their FE meshes employing the object-oriented approach based on the parametric and top-down design. Also "MeshGen" reduces dramatically the time required to prepare CAD models under window-based environments on desktop personal computers and makes it much easier and faster for end-users to change topology and material properties.

• KIEAE Journal
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• v.12 no.2
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• pp.25-32
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• 2012

This paper focused on the daylighting performance of residential high-rise buildings in South-Korea. the purpose of this study is to estimate the visual environment of sunlight coming into opening according to sky conditions, orientation of windows and each space of Apartment buildings. Season of the year, weather, and time of day combine with predictable movement patterns of the sun to create highly variable and dynamic daylighting conditions. Daylighting design is usually based on the dominant sky condition and the micro-climate for the building site. There are three common sky conditions: clear sky, overcast sky, and partly cloudy sky. The clear sky includes sunshine and is intense and brighter at the horizon than at the zenith, except in the area around the sun. Daylight received within a building is directly dependent upon the sun's position and the atmospheric conditions. Easily used charts, diagrams, and software programs allow study of solar geometry for any geographic location and time of day. on the other hand, the overcast sky is characterized by diffuse and variable levels of light and has dense cloud cover over 90% of the sky. This paper was calculated by a Desktop Radiance program. The space dimensions were based on a unit module of real constructed apartment having divided into five sections such as living room, room1, room2, room3 and kitchen.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.602-604
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• 2011

Due to wide usage of smartphones and mobile internet, mobile devices are used in various fields such as sending SMS, participating SNS, retrieving information and the number of users taking advantage of them are growing. The keypads of a mobile device are relatively smaller than those of desktop computers. Thus, the user has a difficulty in input sentences quickly and correctly. In this study, we introduce some string recommendation and modification techniques which can be used for helping a user input in mobile devices quickly and correctly. We describe a TRIE dictionary and n-gram language model which are the main technologies of the keyword recommendation applied to the online search engines.

• Journal of the Ergonomics Society of Korea
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• v.32 no.1
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• pp.69-75
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• 2013

Objective: This study proposes an alarm display and compares it with the one(alarm tile display) widely used in main control rooms(MCRs) of nuclear power plants. Background: Catching up with the rapid development of computer technologies, advanced MCRs has been required. Using modern technologies of computers and visual displays, we have a lot of potential to improve user performance and satisfaction as well as safety in MCRs. Method: The alarm bar display has been proposed to reduce some potential problems of the alarm tile display in this study. Human factors evaluations were conducted to compare both types of displays. Two interfaces of bar alarm and tile alarm were simulated on the desktop computer for the user-involved experiment. Eight students participated in the experiment with the within-subject design. Results: The alarm bar was slightly better in terms of situation awareness, and preferred to understand alarm dynamics. The alarm tile was slightly or significantly better in other measures. Conclusion: Both alarm displays have their own advantages and disadvantages. Therefore, combining benefits of both displays can be used to optimize the design of alarm displays. Application: The proposed display is expected to compensate the existing displays for certain purposes.