• Proceedings of the Membrane Society of Korea Conference
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• 2008.05a
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• pp.33-47
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• 2008

Non-equilibrium (irreversible) themodynamics is used to investigate colloidal back-diffusion during crossflow membrane filtration. The chemical potential is generalized as a superposition of equilibrium and irreversible contributions, originating from Brownian and shear-induced diffusion, respectively. As a result, an effective drag force is derived using the irreversible thermodynamics for a particle undergoing both Brownian and shear-induced diffusion in a sheared concentrated suspension. Using the drag force, a hydrodynamic force bias Monte Carlo method is developed for crossflow membrane filtration to determine the critical flux of hard sphere suspensions. Effects of shear rate and particle size on the critical flux are studied, and results show a good agreement with experimental observations reported in the literature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.964-973
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• 1997

A tidal prism eutrophication model, an one-dimensional intertidal model, is developed to study water quality conditions at small coastal basins and tidal creeks. The model simulates the physical transport processes using the concept of tidal flushing. The concept is simple and straightforward, and thus is ideal for small coastal basins with complex geometry. The model, having twenty-four state variables in the water column, simulates salinity, temperature, dissolved oxygen, three algal groups, and the cycles of carbon, nitrogen, phosphorus and silica. The model is applied to the Lynnhaven Bay, a small coastal basin of Chesapeake Bay in U.S.A. The model is calibrated using the field data collected in 1994, and then is verified using the independently collected data in 1980. The model overall gives a good reproduction of the field data, partly owing to the data collected from the field surveys specifically designed for the model application. This paper presents the procedure, and the results of the model calibration and verification.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.745-746
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• 2006

This lecture introduces new press, adapter and control concepts to size multi-level sintered components. The essential thing here is that the advantages of the multi-plate technology have been applied to the sizing adapter concept. Thus, the new concept meets the demands for a modern P/M manufacture and offers sufficient potential to size any future, complex sintered components such as synchronizer hubs, oil pump wheels and VCT parts with highest precision. Furthermore, it outlines a new flexible concept for the parts transfer, including feeding, orientation and lubrication while responding to the high demands on process stability and short change-over times.

• Journal of the Korean Graphic Arts Communication Society
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• v.24 no.2
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• pp.11-24
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• 2006

The Lithographic ink is composed of pigment, vehicle and additives. In especially, the vehicle is the most important element and consist of vegetable oils, mineral oils and resins. Varnishes have to resist certain forms of chemical and physical attack during ink manufacturing process and printing process So this varnish cooking is very important. In this paper, effects of cooking conditions of varnish using phenolic modified rosin ester on physical properties of the vehicle were studied. The varnish cooked according to temperature and time were compared in order of average molecular weight by the GPC method. and the rheological properties were found by rotational rheometer. And the emulsion behavior were compared by high speed emulsification tester which were set on 1200 rpm and $40^{\circ}C$ temperature (Novomatics Lithotronic). We displayed viscosity against tack(Inkometer Thwing-Albert M-106) by diagram.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2006.02a
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• pp.125-126
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• 2006

NimbleGen has developed strategies to use its high-density oligonucleotide microarray platform (385,000 probes per array) to map both promoter binding sites and copy number variation at very high-resolution in the human genome. Here we describe a genome-wide map of active promoters determined by experimentally locating the sites of transcription imitation complex binding throughout the human genome using microarrays combined with chromatin immunoprecipitation. This map defines 10,567 active promoters corresponding to 6,763 known genes and at least 1,196 un-annotated transcriptional units. Microarray-based comparative genomic hybridisation (CGH) is animportant research tool for investigating chromosomal aberrations frequently associated with complex diseases such as cancer, neuropsychiatric disorders, and congenital developmental disorders. NimbleGen array CGH is an ultra-high resolution (0.5-50 Kb) oligo array platform that can be used to detect amplifications and deletions and map the associated breakpoints on the whole-genome level or with custom fine-tiling arrays. For whole-genome array CGH, probes are tiled through genic and intergenic regions with a median probe spacing of 6 Kb, which provides a comprehensive, unbiased analysis of the genome.

• Wind and Structures
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• v.3 no.1
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• pp.11-21
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• 2000

This paper presents results of modeling of the passive contaminant diffusion from a continuous line finite-size source located on the underlying surface of a neutral near-ground atmospheric layer obtained by using the non-local two-parameteric turbulence model and the transport equation of mean concentration. In the proposed diffusion model the turbulent diffusion coefficient changes not only with the vertical coordinate but also with the distance downstream from the source according to the experimental data. The results of the modeling reproduce structural features of the concentration field.

• Research in Mathematical Education
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• v.23 no.2
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• pp.93-111
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• 2020

The purpose of this study was to examine mathematics teachers' perceptions of multicultural education. To achieve this goal, the study explored how 10 elementary mathematics teachers noticed multicultural content in a mathematics textbook. Building upon noticing framework (Jacobs, Lamb, & Philipp, 2010), we first examined teachers' attention toward multicultural content in a mathematics textbook. Then, we examined teachers' interpretation of the content. We employed a content analysis approach to examine the collected data. The results indicated that most mathematics teachers held a content integration perspective. Their view was that "multicultural education" referred to learning about the diverse cultures of different countries. Moreover, although they noticed some multicultural content in the textbook, they wanted to discuss them in superficially descriptive ways and avoid talking about social justice issues. Additionally, some teachers believed that mathematics is a culture-free subject. They argued that multicultural content should not be presented in mathematics textbooks. We also discussed uncommon themes, which were reported by only a few mathematics teachers.

• Proceedings of the Korea Information Processing Society Conference
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• 2014.04a
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• pp.226-229
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• 2014

편측무시는 뇌졸중 환자에게서 나타나는 지각 손상중의 하나로 말초 운동 및 감각 신경의 손상과 상관없이 손상된 대뇌반구의 반대편의 공간과 신체의 지각이 감소된 상태로 양방향에서 동시에 주어지는 자극에 대해서 한쪽 자극만을 지각하며 뇌손상 반대편의 신체 움직임의 인식 부족과, 무시된 공간쪽으로의 적은 눈 움직임을 보인다. 이와 같은 편측무시를 측정하는 기존 방법으로는 Albert Test, Line bisection Test, Star Cancellation Test 등이 있다. 하지만, 기존 편측무시 평가 방식에는 여러 가지 단점들이 발생한다. 항상 새로운 평가용지가 필요, 검사시간이 오래 소모되고, 모든 작업을 수작업으로 진행, 종이로 데이터를 관리, 수작업이므로 인력낭비 발생한다. 따라서 본 논문에서는 이러한 아날로그 방식에서 나오는 문제점들을 누구나 사용하고 있는 스마트 디바이스를 이용해 디지털방식으로 전환하여 기존의 비효율적이던 방식을 개선시키고자 평가시스템을 개발하고자 한다.

• Korean Journal of Remote Sensing
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• v.25 no.2
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• pp.165-173
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• 2009

Augmented Reality technologies offer new possibilities to the exploration of spatial distributed information. In this work we describe the main issues in the development of an Augmented Reality system that allows the annotation of objects or features in the real world captured by a camera. The general operation of this kind of systems is described, as well as the main problems that need to be solved. Finally, as an example of case of study, we present an application for the annotation of information relative to containers in a marine terminal.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.184-184
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• 2017

A nation-wide water-energy-food (WEF) nexus simulation model has been developed by the authors and successfully applied to South Korea to predict the sustainability of those three resources in the next 30 years. The model was also capable of simulating future scenarios of resources allocation based on priority rules aiming to maximize resources sustainability. However, the process was still relying on several assumptions and trial-and-error approach, which sometimes resulted in non-optimal solutions of resources allocation. In this study, an optimization module was introduced to enhance the model in generating optimal resources management rules. The objective of the optimization was to maximize the reliability index of resources by determining the resources' allocation and/or priority rules for each demand type that accordingly reflect the resources management policies. Implementation of the optimization module would result in balanced allocation and management of limited resources and assist the stakeholders in deciding resources' management plans, either by fulfilling the domestic production or by global trading.