• 한국산학기술학회논문지
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• 제10권8호
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• pp.1843-1849
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• 2009

실시간 3D 그래픽에서 렌더링 성능을 향상시키는 기법 중 하나로 파이프라인 최적화가 있다. 파이프라인 최적화는 버퍼 재 정렬 문제로 볼 수 있다. 그러나 이는 NP-hard이다. 따라서 최적의 해를 근사하며 실시간 3D 그래픽에 적합한 알고리즘 개발이 필요하다. 본 논문은 이를 위해 실시간 3D 그래픽의 렌더링 상태 변화 비용의 패턴을 분석하였다. 그리고 분석된 패턴을 기반으로 렌더링 상태 변화 비용이 큰 것에 대하여 우선적으로 정렬하는 알고리즘을 제시한다. 제안 기법의 우수함을 보이기 위해, 상태비용을 정렬하지 않는 알고리즘과 성능을 평가한다. 제안 방법은 상태비용을 정렬하지 않는 알고리즘에 비해 약 2.5배-4배 정도 비용이 감소되며. 특정 렌더링 상태의 변화 비용이 크게 증가할수록 우수함을 보인다.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.150-153
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• 2015

The construction industry is an integral part of any nation's economy, whether measured by dollar volume or workforce size. In spite of its strong influence, there has been very little specifically aimed at evaluating the current industry performance. This research investigates the macroeconomic performance of the construction industry by accounting for crucial performance affecting factors such as labor productivity and gross margin. A clustering analysis, followed by a series of statistical analyses, yielded a notable finding that labor productivity is the most important factor that affects industry's profitability. The results of the analysis also revealed that the states with the strongest labor productivity show the highest level of profitability in terms of gross margin. This study should be of value to decision-makers when plotting a roadmap for future growth and rendering a strategic business decision.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.58-58
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• 2010

Reactive or unstable adsorbates are often difficult to study spectroscopically. They may have, for instance, resonance states lying close to the Fermi level, inducing them to desorb or decompose by the probe itself, low-energy tunneling electrons. In order to overcome this limitation, we developed a novel method, which we call x-ramp scan. The method sweeps the bias voltage, with the simutaneous scan along the imaging direction, in a constant current mode. This mapping yields the tip-height variation as a function of bias, or Z(V), at nominally always fresh surface. We applied this method to the investigation of methanol-induced molecular features, attributed to methoxy, found on NiAl(110) surface. These were produced by methanol molecules deposited by a pulse injection method onto the metallic surface. Our study shows adsorbed methoxy are very reactive to the bias voltage, rendering the standard spectroscopy useless. Our new x-ramp scan shows that the decomposition of adsorbates occurs at the sample bias of 3.63 V, and proceeds with the lifetime of a few milliseconds. The details of the method will be provided at the discussion.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권4호
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• pp.189-197
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• 2003

The problem of designing a parallel feedforward compensator (PFC) is considered for a class of non-square linear systems such that the closed-loop system is strictly passive. If a given square system has (vector) relative degree one and is weakly minimum phase, the system can be rendered passive by a state feedback. However, when the system states are not always measurable and the given output is considered, passivation (i.e. rendering passive) of a non-minimum phase system or a system with high relative degree cannot be achieved by any other methodologies except by using a PFC. To passivate a non-square system we first determine a squaring gain matrix and design a PFC such that the composite system has relative degree one and is minimum phase. Then the system is rendered strictly passvie by a static output feedback law. Necessary and sufficient conditions for the existence of the PFC and the squaring gain matrix are given by the static output feedback formulation, which enables to utilize linear matrix inequality (LMI). As an application of the scheme, an alternative way of replacing the role of velocity measurements is provided for the PD-control law of a convey-crane system.

• Environmental Engineering Research
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• 제10권1호
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• pp.38-44
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• 2005

Electro-thermal production of white phosphorus(WP, P4) generates substantial amount of highly toxic phossy water and sludges. Because of their high phosphorus contents and lack of reliable processing technology, large tonnages of these hazardous wastes have accumulated from current and past operations in the United States. In this study, two different methods for treatment of phosphorus sludge were investigated. These were bulk removal of WP by physical separation(froth flotation) and transformation of WP to oxyphosphorus compounds by air oxidation in the sludge medium. Kerosene, among other collectors, resulted in selective flotation of WP from the associated mineral gangue. Solvent action of kerosene occurring on the WP surface(by rendering WP particles hydrophobic) might produce the high selectivity of WP. The WP recovery in the froth was 79.3% from a sludge assaying 34.2% of WP. In the oxidation study, air gas was dispersed in the sludge medium by the rapid rotation of the impeller blades. The high level of sludge agitation intensity caused a fast completion of the oxidation reactions and it resulted in the high percentage conversion of WP to PO4-3 with PO3-3 making up almost all portion of oxyphosphorus compounds. The WP analysis on the treated sludge showed that supernatant solution and solid residue contained an average of 4.2 μg/L and 143 ppm respectively from the sludge containing about 26 g of WP. Further investigation will be required on operational factors to better understand the processes and achieve an optimum condition.

• 한국정보통신학회논문지
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• 제19권1호
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• pp.119-126
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• 2015

본 논문에서는 항만컨테이너 운영 모니터링 및 계획 시뮬레이션의 결과를 3차원으로 정적 동적 개체를 포함하는 주변 환경의 거동을 시각적으로 표현하고 실제 작업이 이루어지는 애니메이션을 통해 운영모델을 직관적으로 평가가 가능한 시뮬레이션 가시화 시스템을 제안한다. 제안한 항만 시뮬레이션 가시화 시스템(PSVS)은 객체의 상태를 XML기반으로 설계하여 기존의 항만 운영 시뮬레이션(CATOS)과 상호운용성에 있어서 연동성을 극대화하고 실시간으로 대규모 객체에 대한 애니메이션 표현이 가능하도록 구현하였다. 본 논문에서는 PSVS시스템의 설계 방법에 대해서 설명하고 실험을 통해 PSVS의 타당성을 검토하였다.

• 한국정보통신학회논문지
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• 제12권3호
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• pp.438-444
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• 2008

본 논문에서는 애니메이션 캐릭터의 표정 연출의 효율성을 높이기 위해 정서 상태의 변화에 따라 다양하고 주어진 상황에 부합하는 표정을 쉽게 구현할 수 있는 표정생성 프로그램을 제안하고자 한다. 이를 위해 우선, Russell의 내적 정서 상태의 차원 모형을 근거로 쾌-불쾌, 각성-비각성의 내적 정서 상태 정보를 포함한 9가지 표정을 정의하였다. 그리고 각각의 표정에 대해 본 연구에서 제안한 표정생성 프로그램을 이용하여 두 차원의 중앙에 위치하는 무표정 자극을 8가지의 가능한 표정 변화 방향으로 이동시킴으로써 정서 차원에서의 미묘한 위치 변화에 따라서도 다양한 표정 생성이 구현될 수 있음을 확인하였다. 향후 이러한 프로그램은 복잡한 정서를 가진 표정을 쉽고 다양하게 구현할 수 있는 표정 자동생성 시스템 설계의 기초적 프로그램으로 활용될 수 있을 것이다.

• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.269-278
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• 2007

Nighttime construction is being adopted by many state DOT's as a way to mitigate the impact of construction operations on the traveling public. Although a number of states have developed standard specifications for nighttime lighting, these standards are usually in the form of generic requirement statements that only specify minimum illuminance levels. The lighting standards do not include specific ways to achieve this illuminance level such as lighting arrangements and configurations for various work zone plans and construction operations. This leaves confusion between the traffic engineers and the contractors and does not guarantee consistency in those plans, thus affecting productivity and safety (lighting conditions account for 18% to 28% of work zone accidents). The main objective of this study is to utilize three dimensional animation and lighting analysis software to study and model lighting conditions of a construction site. This is expected to increase the safety and productivity of construction operations by achieving consistency in work zone lighting schemes. A computerized model was developed, called Nitelite. Various lighting schemes can be studied using the software to provide for typical applications including lighting fixture's locations, luminance, mounting height, tilt angle, and fixture type. The results from the developed software tool were validated through comparisons with previous research conducted using field measurements.

• 영어영문학
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• 제57권3호
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• pp.413-428
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• 2011

Compared with Cathy Song and Myung-Mi Kim, Suji Kwock Kim is yet to be known in Korea, even though she won prestigious American literary awards like the Walt Whitman Award from the Academy of American Poets and the Addison Metcalf Award from the American Academy of Arts and Letters for her debut book of poems, Notes from the Divided Country. Although she was born and raised in the United States and had little knowledge of Korean at first, she came to recognize her identity and be familiar by and by with Korean history. The knowledge of the facts that Korea had been ravaged by foreign forces and suffered from the Japanese colonization and the Korean War aches her soul, and this soul-aching is aggravated by her ancestors' direct experiences of those Korean historical tragedies. But this book of poems does not contain poems regarding Korean history alone. The first part shows her guilty consciouseness for her brother and sister, who are suggested to be physically abnormal or mentally retarded. The third and fourth parts are filled with poems of very diverse subject matters, tones, and themes. Of those poems, "Monologue for an Onion" is probably most worthy of special attention. It is not only a searing indictment for human folly but also a very intriguing poetic rendering of Nietzschean ultimate lessson. Her achievement in the first book of poems makes us eagerly wait for the second one, which is, reportedly, forthcoming sooner or later.

• Strategy21
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• 통권41호
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• pp.5-29
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• 2017

The Mahan's seapower theory has been the basis of US Navy to date as it can enjoy the supremacy status in all of the seas of the world. His theory is very straightforward. A nation can be a great country in the world just through the use of maritime commerce that could be protected by a strong and powerful navy. Mahan's theory on seapower was substantiated in the Spanish-American War with respect to how important the naval power is. The best thing to make US a great nation was to make sure that flow of international trade is smooth, and the unhindered trade could be made possible only by the destruction of enemy's fleet that may obstruct the SLOCs. That's why Mahan insisted that a strong navy was needed and a decisive battle by the navy's fleet at sea should be encouraged as a way of ensuring the safety of the SLOCs. The newly-arrived Trump administration seems to be in line with the Mahan's theory seapower in its policy on naval forces structure. It is expected that US will continue to support the Pivot to Asia policy that has been adopted by the previous administration through an increase in its naval fleet forces. The number of US navy ships will be 355 in 2030, rendering it much more powerful navy than before. The catch phrase "3rd Fleet Forward" proposed by the president Trump indicates that two carrier strike groups will be present in the Asia Pacific region, being able to make the confrontation between US and China more tense than before. The presence of the US naval forces in the area may function as some sort of pressure against China that Trump insisted had been responsible for the closure of 60,000 factories and the loss of 3,000,000 jobs in the United States.