• 한국정보과학회논문지:소프트웨어및응용
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• 제31권12호
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• pp.1611-1620
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• 2004

MPEG-4는 객체의 삽입/삭제/교체 또는 객체의 속성 변경을 통하여 동적인 장면 구성을 지원한다. 기존의 MPEG-4 재생기들은 MPEG-4 표준에 따라 멀티미디어 데이타를 전송하고 재생하는데 치중하여 MPEG-4의 특징인 다양한 객체의 지원이나 동적인 장면 구성의 지원이 미흡했다 본 논문에서는 MPEG-4 재생기의 핵심 구성요소인 효율적인 장면 구성기를 제안한다. 장면 구성기는 장면 그래프를 효율적으로 탐색하고, 자료구조를 생성하여 객체 정보를 그 특성에 맞게 관리하며, 상호작용 처리 능력을 향상시킨 최적의 처리기이다. 장면 구성기는 장면 기술 정보를 충분히 지원하며, 구성요소 확장과 모바일 환경에 적용하기 위해 재생기에서 독립적으로 관리된다.

• Journal of Power Electronics
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• 제12권6호
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• pp.886-894
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• 2012

This paper presents a secondary-side, dual-mode feedback LLC resonant controller IC with dynamic PWM dimming for LED backlight units. In order to reduce the cost, master and slave outputs can be generated simultaneously with a single LLC resonant core based on dual-mode feedback topologies. Pulse Frequency Modulation (PFM) and Pulse Width Modulation (PWM) schemes are used for the master stage and slave stage, respectively. In order to guarantee the correct dual feedback operation, Phased-Locked Loop (PLL)-based automatic duty control circuit is proposed in this paper. The chip is fabricated using $0.35{\mu}m$ Bipolar-CMOS-DMOS (BCD) technology, and the die size is $2.5mm{\times}2.5mm$. The frequency of the gate driver (GDA/GDB) in the clock generator ranges from 50 to 425 kHz. The current consumption of the LLC resonant controller IC is 40 mA for a 100 kHz operation frequency using a 15 V supply. The duty ratio of the slave stage can be controlled from 40% to 60% independent of the frequency of the master stage.

• Journal of Information Processing Systems
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• 제1권1호
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• pp.41-48
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• 2005

This paper presents the development of a morphological processor for the Mongolian language, based on the two-level morphological model which was introduced by Koskenniemi. The aim of the study is to provide Mongolian syntactic parsers with more effective information on word structure of Mongolian words. First hand written rules that are the core of this model are compiled into finite-state transducers by a rule tool. Output of the compiler was edited to clarity by hand whenever necessary. The rules file and lexicon presented in the paper describe the morphology of Mongolian nouns, adjectives and verbs. Although the rules illustrated are not sufficient for accounting all the processes of Mongolian lexical phonology, other necessary rules can be easily added when new words are supplemented to the lexicon file. The theoretical consideration of the paper is concluded in representation of the morphological phenomena of Mongolian by the general, language-independent framework of the two-level morphological model.

• Transactions on Electrical and Electronic Materials
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• 제12권6호
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• pp.241-244
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• 2011

An isolator transmits light in the forward direction and blocks light from passing in the reverse direction. It is regarded an essential optical component in medical, industrial, and research lasers for blocking reflection beams that cause optical damage and noise. It is also used as a communicative light intensifier to expand the lifespan of devices and enhance transmission quality. This study analyzed the characteristics of the core components in the construction of a polarization-independent isolator, namely, the walk-off polarizer and the Faraday rotator. Measurement of the extinction ratio of the resultant walk-off polarizer revealed that the ratio between the vertical and horizontal rays was 1,050:1 with a laser output of 0.032 W and 1,010:1 with a laser output of 2.68 W, thus presenting ratios similar to 1,000:1. In addition, the walk-off polarizer and Faraday rotator constructed in this study were used to compare output changes according to changes in power of input light and to check the penetration ratio. Results from the study presented variations in output value according to changes in power of input light. However, the average penetration ratio remained relatively consistent (~81.4%).

• Journal of Photoscience
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• 제9권3호
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• pp.65-70
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• 2002

In the rice leaves treated with methyl viologen (MV), the photochemical efficiency of PSII (or $F_{v/}$F $m_{m}$) was significantly decreased, and significant portion of the photoinactivation process was reversible during the dark-recovery. The dark-reactivation process was relatively slow, reaching its plateau after 2-2.5 h of dark incubation. The damaged portion of functional PSII was 13％, based on the value of I/ $F_{o}$- I/ $F_{m}$ after this dark-recovery period. The reversible photoinactivation process of PSII function in the MV-treated leaves consisted of a xanthophyll cycle-dependent development of NPQ and a xanthophyll cycle-independent process. The latter process was reversible in the presence of nigericin. As well as the increase in the values of Chl fluorescence parameters, the epoxidation process during the dark-recovery after the MV-induced photooxidation was very slow. These results suggest that the photooxidative effect of MV is partly protected by the down-regulation of PSII before inducing physical damages in core proteins of PSII.I.I.I.I.

• 한국정밀공학회지
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• 제33권9호
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• pp.739-744
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• 2016

The truck that is used as running equipment for tank freight car support is a core structural part that supports the load of the car body and significantly influences the safety of freights and vehicles, as well as their running performance. Running equipment is composed of truck frames, wheels and wheel axles, independent suspensions, and brakes. Among these components, the truck frame supporting the load of the vehicles and freights may be the most important component. This study was carried out to analyze the structure of truck frames and to determine whether they are safe when the maximum vertical load, braking part load, and the front and rear load are applied to truck frames. This was achieved by subjecting the truck frames to stress tests and then measuring the stress on each part. The results of the stress tests showed that truck frames have a safe vehicle load design.

• 제어로봇시스템학회논문지
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• 제11권2호
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• pp.152-159
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• 2005

This paper describes the application of a model-based system design method critical to complex intelligent systems, PSARE, to a welding robot development to define its top level architecture. The PSARE model consists of requirement model which describes the core processes(function) of the system, enhanced requirement model which adds technology specific processes to requirement model and allocates them to architecture model, and architecture model which describes the structure and interfaces and flows of the modules of the system. This paper focuses on the detailed procedure and method rather than the detailed domain model of the welding robot. In this study, only the top level architecture of a welding robot was defined using the PSARE method. However, the method can be repeatedly applied to the lower level architecture of the robot until the process which the robot should perform can be clearly defined. The enhanced data flow diagram in this model separates technology independent processes and technology specific processes. This approach will provide a useful base not only for improvement of a class of welding robots but also for development of increasingly complex intelligent real-time systems.

• 한국압력기기공학회 논문집
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• 제15권1호
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• pp.33-39
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• 2019

An 1,500MW advanced power reactor required the standard design approval by a Korean regulatory body in 2014. The reactor has been designed to have a 4-train independent safety concept and a passive auxiliary feedwater system (PAFS). The full power risk or core damage frequency (CDF) of 1,500MW advanced power reactor has been reduced more than that of APR1400. However, the risk during the low power and shutdown (LPSD) operation should be reduced because CDF of LPSD is about 4.7 times higher than that of internal full power. The purpose of paper is to analysis design alternatives to reduce risk during the LPSD. This paper suggests design alternatives to reduce risk and presents sensitivity analysis results.

• 천문학회보
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• 제43권2호
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• pp.33.2-33.2
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• 2018

Fossil galaxy cluster has a dominant central elliptical galaxy (${\Delta}M12$ >2 in 0.5Rvir) embedded in highly relaxed X-ray halo, which indicates dynamically stable and passively evolved system. These features are expected as a final stage of the cluster evolution in the hierarchical structure formation paradigm. It is known that Abell 2261(A2261 hereafter) is classified as a fossil cluster, but has unusual features such as a high central X-ray entropy (i.e., non-cool core system), which is not expected in normal fossil clusters. We perform a kinematic study with a spectroscopic data of 589 galaxies in the A2261 field. We define cluster member galaxies using the caustic method and discover a new second bright galaxy at ~1.5 Rvir (nearly the splash-back region). It implies the current fossil state of the cluster can break in the near future. In addition, with three independent substructure finding methods, we find that A2261 has many substructures within 3 Mpc from the center of the cluster. These findings support that A2261 is not in a dynamically stable state. We argue that A2261 is in a transitional phase of dynamical evolution of the galaxy cluster and maybe previously defined fossil cluster does not mean the final stage of the evolution of galaxy clusters.

• Mycobiology
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• 제49권1호
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• pp.24-45
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• 2021

The occurrence of Austroboletus subflavidus and Fistulinella gloeocarpa is documented from the Dominican Republic. The latter species is reported for the first time outside its original locality in Martinique, extending the geographic range for this uncommon pinkish-spored bolete. A detailed morphological description is provided for each species and accompanied by color pictures of fresh basidiomes in habitat and line drawings of the main anatomical features. Both species represent independent lineages within their respective genera based on phylogenetic inference. In addition, A. subflavidus clusters in a sister lineage to the core Austroboletus clade (Austroboletus clade I) here named as Austroboletus clade II. In order to confirm the accuracy of species identification, their identity and relationships were subjected to multilocus phylogenetic analyses of three gene markers (ITS, nrLSU, RPB2) including genetic material already available in public databases. Austroboletus subflavidus is a widely distributed species in North and Central America, whereas F. gloeocarpa is apparently highly localized and seems to appear sparingly in the Dominican Republic, Martinque, and southern Florida. Comparisons with morphologically similar and molecularly inferred allied species are also presented and discussed.