• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2001년도 추계학술발표회
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• pp.137-144
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• 2001

A Plankton ecosystem model was developed to investigate effects of hydrodynamic processes including advection and diffusion on size-structured phytoplankton dynamics in the mesohaline zone of the York River estuarine system, Virginia, USA. The model included 12 state variables representing the distribution of carbon and nutrients in the surface mixed layer. Groupings of autotrophs and heterotrophs were based on cell site and ecological hierarchy Forcing functions included incident radiation, temperature, wind stress, mean How and tide which includes advective transport and turbulent mixing. The ecosystem model was developed in FORTRAN using differential equations that were solved using the 4th order Runge-Kutta technique. The model showed that microphytoplankton blooms during winter-spring resulted from a combination of vertical advection and diffusion of phytoplankton cells rather than in-situ production in the lower York River estuary.

• The Korean Journal of Ceramics
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• 제1권1호
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• pp.29-34
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• 1995

Theoretical predictions were made for thermodynamically stable phases which formed when alkali(sodium and Potassium) vapors reacted with the 90% $Al_2O_3$-10% $Cr_2O_3$ refractory under coal gasifying atmosphere using the computer program of SOLGASMIX-PV. The calculation results showed that the stable compounds that formed were $X_2O$.$Al_2O_3$ and $X_2O$.$llAl_2O_3$(X=$Na^+$ or $K^+$), depending upon the alkali concentration. The presence of sulfur in gasifying atmospheres did not appear to affect the species of alkali reaction products. Alkali attack at high temperatures is likely to cause serious degradation at the hot face of the refractory, indicating that the alkali concentration is an important factor to affect the degradation of the refroctory.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제23권2호
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• pp.113-133
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• 2020

Pre-service teachers (PST) are students who are developing their mindset, persistence, instructional practices, and perception of tasks from two perspectives: as current students and as future teachers. As part of a larger study with PSTs engaged in a mindset intervention, this study quantitatively investigated PSTs mindset and persistence. During professional development (PD), PSTs engaged in multiple strategies (MS) tasks that promoted changes to PSTs mindset and persistence. PSTs' mindset pre- and post- PD were categorized after attending at least 4 interventions as fixed, mixed, or growth using the theory of intelligence, and their persistence as high or low using the Grit-S. Changes in categorization were noticed and explored for reasons of what could be done to make mindset interventions more effective such as consistently using challenging mathematics tasks with more open ended answers and focusing on discussion based mathematical lessons.

• 한국농공학회지
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• 제44권3호
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• pp.65-72
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• 2002

Rainfall and runoff data from a forested watershed and irrigated rice paddies at the Bal-an experimental watershed were monitored and analyzed to investigate the variations of runoff characteristics with different land use. The comparisons were conducted fourteen storm events ranging 21.8∼190.2 mm of rainfall. Field data showed that direct runoff from paddies and forested watershed are not significantly different in volume. The peak discharge from forest watershed was less than that from paddies far lighter storms, but became greater fur heavier storms. The peak runoff from the forest watershed was 39 percent greater than from the paddies. The results demonstrate that paddies play an important role to reduce peak discharge from heavy storms as compared to forest.

• Journal of Computing Science and Engineering
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• 제6권4호
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• pp.267-278
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• 2012

The state-of-the-art techniques in multicore timing analysis are limited to analyze multicores with shared instruction caches only. This paper proposes a uniform framework to analyze the worst-case performance for both shared instruction caches and data caches in a multicore platform. Our approach is based on a new concept called address flow graph, which can be used to model both instruction and data accesses for timing analysis. Our experiments, as a proof-of-concept study, indicate that the proposed approach can accurately compute the worst-case performance for real-time threads running on a dual-core processor with a shared L2 cache (either to store instructions or data).

• 한국시뮬레이션학회논문지
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• 제8권4호
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• pp.33-51
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• 1999

In this study, the system level network simulation is considered with adaptive array antenna in CDMA mobile communication system. A network simulation framework is implemented based on IS-95A/B system to consider dynamic handoff, system level network behavior, and deploying strategy into the overall CDMA mobile communication network under adaptive array algorithm. Its simulation model, such as vector channel model, adaptive beam forming antenna model, handoff model, and power control model, are described in detail with simulation block. In order to maximize SINR of received signal at antenna, Maximin algorithm is particularly considered, and it is computed at each simulation snap shot with SINR based power control and handoff algorithm. Graphic user interface in this system level network simulator is also implemented to define the simulation environments and to represent simulation results on real mapping system. This paper also shows some features of simulation framework and simulation results.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제24권2호
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• pp.83-109
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• 2021

In the early stage of lesson enactment process, teachers use textbooks and other resources to select tasks and activities. It follows that discrepancies between textbooks and research-recommended pathways for learning may lead to concerns or issues with pacing in the classroom. To explore this idea further, this study examined the alignment between three popular standards-aligned textbooks series and volume learning trajectories. The results indicated that the standards-based textbooks examined may lack attention to important topics in the pacing of volume instruction, and suggest the need to inform both pre-service and in-service teachers about the gap between textbook lessons and volume learning trajectories so that they will be able to reflect students' thinking in volume learning trajectory to their lessons.

• International Journal of Human Ecology
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• 제7권1호
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• pp.111-119
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• 2006

The purpose of our study is to explore dynamic mechanisms within families and self-authored decisions among Korean female college students. In particular, we investigated how parent-child interactions influence the development of self-authorship and self-authored decisions within Korean culture through interviews with 14 female college students. Results showed unique cultural influences on how female college students interacted with parents and interpreted and reflected parents' opinions in their self-authored decisions. These results suggest further research on gender differences and complex family influences on self-authored decisions within cultural contexts.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.436-436
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• 2012

하수처리수의 농업용수 재이용에는 직접재이용과 간접재이용이 있으며 대부분의 경우 간접재이용의 형식으로 하수처리수가 농업용수로 이용되고 있다. 전국 130여개의 하수처리장 방류수가 논을 포함한 인근 농경지의 관개용수에 영향을 미치고 있으나 적절한 처리과정 없이 농업용수로 사용되고 있으며, 이는 농민과 농산물 그리고 소비자에게 보건 위생적 영향을 미칠 수 있다. 따라서 하수처리수를 안전하게 농업용수로 간접재이용할 수 있는 연구가 수반되어야 한다. 본 연구에서는 하수처리수의 농업용수 간접재이용에 따른 작물생육, 수질, 토양 환경영향 및 인체위해성 평가 등을 포함한 기초연구를 3년간 진행할 계획이다. 또한 본 연구를 통해서 간접재 이용지구의 유형을 구분하고 이에 따른 저비용, 고효율의 수처리 공정을 개발하며, 간접재이용을 위한 적정 수질기준을 정립하고자 한다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.792-801
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• 1996

A thinning algorithm -based image analysis technique was developed to measure corn root lengths. The root length measurement method was evaluated by comparing thread lengths measured by the image analysis system with actual thread lengths. The length measurement method accurately estimated actual thread lengths (less than 2% calculated error). Also, a rapid root length density measurement procedure, which utilizes the above root length measurement method, was developed to estimate corn root length density without washing the roots. Root length densities estimated from the cut soil surface of core samples taken from the field were paired with the root length densities determined from washed roots from the same soil core sample. A linear relationship between these two values was expected and was found. Eliminating the root washing procedure reduces the time required for measuring corn root length density substantially.