A Study of the Color Effect on the Changes in Emotion and Behavior

Yang, Wonseok 인제대학교 디자인연구소 2014 Journal of Integrated Design Research (JIDR) Vol.13 No.2

As offices increasingly move into the center of large cities, office workers are short of time to focus on their tasks and unable to improve their efficiency due to commuting time, transportation cost and reduced working space. As a measure to solve such complex issues, "smart office" is drawing attention in recent years. It is also needed to correctly understand the psychological effect of color and which color can improve efficiency. This study aims to investigate how color has an effect on emotional change to improve the efficiency of creative activities in smart office, using an experiment. The experiment was conducted using the Profile of Mood States(POMS) test: a portable form of color paper was placed on the table of office and a creative activity was performed using LEGO blocks. The colors used for the experiment were changed from white and blue to while, blue, green and grey. This study proposed a portable folding color pad to improve the work efficiency of smart office based on 2 experiments.

High Resolution Measurement of Aerosols From Plasma Arc Torch Cuts on Various Metals for D&D Worker Internal Dose Calculation

Wonseok Yang,Min-ho Lee,Nakkyu Chae,Sungyeol Choi 한국방사성폐기물학회 2019 한국방사성폐기물학회 학술논문요약집 Vol.2019 No.10

Development of a Machine Learning Model for Determination of Electrode Surface Area With Voltammetry of Two Rod Electrode in Molten Salts

Wonseok Yang,Yonadan Choi,Sungyeol Choi 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.1

Radioactive wastes, including used nuclear fuel and decommissioning wastes, have been treated using molten salts. Electrochemical sensors are one of the options for in-situ process monitoring using molten salts. However, in order to use electrochemical sensors in molten salt, the surface area must be known. This is because the surface area affects the current of the electrode. Previous studies have used a variety of methods to determine the electrode surface area in molten salts. One method of calculating the electrode surface area is to use the reduction current peak difference between electrodes with known length differences. The method is based on the reduction peak and has the benefit of providing long-term in-situ monitoring of surfaces immersed in molten salt. A number of assumptions have been made regarding this method, including that there is no mass transport by migration or convection; the reaction is reversible and limited by diffusion; the chemical activity of the deposit should be unity; and species should follow linear diffusion. For the purpose of overcoming these limitations, a variety of machine learning algorithms were applied to different voltammogram datasets in order to calculate the surface area. Voltammogram datasets were collected from multiarray electrodes, comprising a multiarray holder, two tungsten rods (1 mm diameter) working electrodes, a quasi-reference electrode, and a counter electrode. The multiarray electrode holder was connected to the auto vertical translator, which uses a servo motor, for changing the height of the rod in the molten salts. To make big and diverse data for training machine learning models, various concentrations of corrosion products (Cr, Fe) and fission products (Eu, Sm) in NaCl-MgCl2 eutectic salts were used as electrolyte; electrolyte temperatures were 500, 525, 550, 575, and 600°C. This study will demonstrate the potential of utilizing machine learning based electrochemical in situ monitoring in molten salt processing.

Effects of Volumetric Energy Density and Build Plate Preheating on the Mechanical Properties of a High-Mg AlMg10ScZr Alloy Processed by Powder Bed Fusion

Wonseok Yang,Young‑Gil Jung,Tae Yang Kwak,Shae K. Kim,Hyunkyu Lim,Do Hyang Kim 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.6

This study aimed to develop a high-strength, low-cost AlMg10ScZr alloy with a higher Mg content and lower Sc content thanthe Al–Mg–Sc–Zr alloy, which is reported to have high strength. A Powder bed fusion process was employed with variousvolumetric energy density (VED) to establish the optimum process conditions. It was found that with increasing volumetricenergy density, the elongation and ultimate tensile strength increased. In addition, it was possible to obtain a sound specimenat a lower VEDthrough preheating of the build plate, confirming that the process efficiency was increased. These enhancedmechanical properties are attributed to an increase in relative density. At a volumetric energy density of 209.9 J mm−3 withthe build plate heated to 180 °C, the best combination of the ultimate tensile strength (529.6 MPa) and elongation (17.3%)was achieved.

AN IMPLEMENTATION OF A REMOTE ENGINEERING LABORATORY USING LABVIEW (FOR DIGITAL LOGIC CIRCUITS)

Wonseok Yang,Myungkoo kim,Kwansun Choi,Changwan Jeon 한국멀티미디어학회 2006 한국멀티미디어학회 국제학술대회 Vol.2006 No.-

In this study Remote Laboratory for Digital Logic circuits was implemented that can test Logic Gate. The Virtual Contents and the Real Circuits are directly executed and these Real Circuit experimental images are provided to the students who are advised to do comparison studies. In this study, a DAQ card is used to confirm the Real Circuit's Input Signals and a PC camera is used to show a real-time experiment image screen to the students. The experimenting students will use LabVIEW web servers to conduct the real experiments, and the experiment results are saved database in which a data administrator will manage after. Other students will use the LabVIEW web server to monitor the stages of the experiment.

Study on a reduction of railway vibration using particle impact dampers

Wonseok Yang,Sangkeun Ahn,Hyoin Koh,Junhong Park 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.춘계 No.-

Sampling for Characterizing Radioactive Aerosol From Activated Metal During Cutting With Plasma Arc Torch for Internal Dose Assessment

Wonseok Yang,Nakkyu Chae,Minho Lee,Sungyeol Choi 한국방사성폐기물학회 2019 한국방사성폐기물학회 학술논문요약집 Vol.2019 No.05

Thermal NaCl-MgCl2 Salt Purification for Reducing Reactor Vessel Corrosion

Wonseok Lee,Wonseok Yang,Jihun Kim,Hyeongbin Kim,Sungyeol Choi 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.2

Molten chloride salts are promising candidates as a coolant for Molten Salt Reactors (MSRs) because of their low cost, high specific heat transfer, and thermal energy storage capacity. The NaCl- MgCl2 eutectic salts have enormous latent heat (430 kJ/kg) and financial advantage over other types of molten chloride salt. Despite the promise of the NaCl-MgCl2 eutectic salt, problems associated with structural material corrosion in the MSR system remain. The hygroscopicity of NaCl-MgCl2 and high MSRs operating temperature accelerate corrosion within structural alloys. Especially, MgCl2 reacts with H2O in the eutectic salt to produce HCl and Cl2, which are known to further exacerbate corrosion by the chlorination of structural materials. Therefore, several studies have worked to purify impurities associated with MgCl2, such as H2O. Thermal salt purification of NaCl-MgCl2 eutectic salt is one method that reduces HCl and Cl2 gas generation. However, MgO and MgOHCl are generated as the byproduct of thermal purification through a reaction between MgCl2 and H2O. The corrosion behavior of MgO within structural alloys after thermal treatment is not well known. This paper demonstrates corrosion behavior within structural alloy after thermal treatment at various temperature profiles of the NaCl-MgCl2 eutectic salt. According to the temperature range, MgCl2·H2O are separated at 100~200°C, and MgOHCl and HCl begin to occur at 240°C or higher. Finally, MgOHCl produces MgO and HCl at 500°C or higher temperatures. After thermal treatments, the H2O, MgOHCl, and MgO content were measured by Thermo Gravimetric Analyzer (TGA) to evaluate significant products causing corrosion. The structural materials were analyzed by the Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS) and using the mass change method to observe the type of localized corrosion, the corrosion rate, and the corrosion layer thickness. This study is possible in that it can reduce economic costs by reducing the essential use of expensive, high-purity molten salts because it is related to a substantial financial cost problem considering the amount of molten salt used in industrial sites.

Uniformity of Droplet of Eutectic NaCl-MgCl2 System for Corrosion Test of Coating Layer

Wonseok Lee,Wonseok Yang,Jihun Kim,Hyeongbin Kim,Taeho Jang,Sungyeol Choi 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.1

Corrosion-related challenges remain a significant research topic in developing next-generation Molten Salt Reactors (MSRs). To gain a deeper understanding of preventing corrosion in MSRs, previous studies have attempted to improve the corrosion resistance of structural alloys by coating surfaces such as alumina coating. To conduct a corrosion test of coating alloys fully immersed in molten salt, it’s important to ensure that the coating application process is carefully carried out. Ideally, coating all sides of the alloy is necessary to avoid gaps like corners of the alloy, while only applying a one-sided coating alloy can lead to galvanic corrosion with the base metals. Using the droplet shape of eutectic salt applied to only one side of the coating alloy would avoid these problems in conventional corrosion immersion tests, as corrosion would occur solely on the coating surface. Although the droplet method for corrosion tests cannot fully replicate corrosion in the MSRs environment, it offers a valuable tool for comparing and evaluating the corrosion resistance of different coating surfaces of alloys. However, the surface area is important due to the effect of diffusion in the corrosion of alloy in molten salt environments, but it is difficult to unify in the case of droplet tests. Therefore, understanding the droplet-alloy properties and corrosion mechanism is needed to accurately predict and analyze these test systems’ behavior highlighting unity for corrosion tests of different coating surfaces of alloys. To analyze the molten salt droplet behavior on various samples, pelletized eutectic NaCl-MgCl2 was prepared as salt and W-, Mo-coating, and base SS316 as samples. At room temperature, the same mass of pelletized eutectic NaCl-MgCl2 was placed on different samples under an argon atmosphere and heated to a eutectic point of 500°C in a furnace. After every hour, the molten droplets were hardened by rapid cooling at room temperature outside the furnace. The mass loss of salts and the contact area of the samples were measured by mass balance and SEM. The shape, surface area to volume ratio, and evaporation of the droplets of NaCl-MgCl2 per each coating sample and hour were analyzed to identify the optimal mass to equalize the contact coating surface of alloys with salts. Furthermore, We also analyzed whether their results reached saturation of corrosion products through ICP-MS. This will be significant research for the uniformity of the liquid-drop shape corrosion test of the coating sample in molten eutectic salts.

Multi-color tunable Ce³⁺–Mn²⁺ cooperative Y₇O₆F₉ vernier phosphors

Yang, Wonseok,Kim, Sung-Hoon,Park, Sangmoon Elsevier 2016 JOURNAL OF ALLOYS AND COMPOUNDS Vol.673 No.-

<P><B>Abstract</B></P> <P>Ce<SUP>3+</SUP>–Mn<SUP>2+</SUP>–doped Y<SUB>7</SUB>O<SUB>6</SUB>F<SUB>9</SUB> vernier phosphors composed of Y<SUB>7(1-<I>p</I>-2<I>q</I>/3)</SUB>Ce<SUB>7<I>p</I> </SUB>Mn<SUB>14<I>q</I>/3</SUB>O<SUB>6</SUB>F<SUB>9</SUB> (<I>p</I> = 0.005–0.1, <I>q</I> = 0–0.1) were prepared using a flux–assisted solid-state reaction. The X-ray diffraction patterns of the resultant phosphors were examined to index the peak positions. The photoluminescence (PL) excitation and emission spectra of the Ce<SUP>3+</SUP>-activated yttrium–oxyfluoride phosphors were clearly monitored with critical emission quenching as a function of Ce<SUP>3+</SUP> content in the Y<SUB>7(1-<I>p</I>-2<I>q</I>/3)</SUB>Ce<SUB>7<I>p</I> </SUB>Mn<SUB>14<I>q</I>/3</SUB>O<SUB>6</SUB>F<SUB>9</SUB>. After doping the Y<SUB>7</SUB>O<SUB>6</SUB>F<SUB>9</SUB> structure with Ce<SUP>3+</SUP> and Mn<SUP>2+</SUP> activators, intense blue and green/orange emission lights were observed in the PL spectra under near-ultraviolet (NUV) excitation. The dependence of the luminescent intensity of the Mn<SUP>2+</SUP> co–doped (<I>q</I> = 0, 0.01, 0.05, 0.1) host lattices on Ce<SUP>3+</SUP> content (<I>p</I> = 0.05, 0.1) was also studied. Co-doping Mn<SUP>2+</SUP> into the Ce<SUP>3+</SUP>–doped host structure enabled high energy transfer from Ce<SUP>3+</SUP> to Mn<SUP>2+</SUP>; this energy transfer mechanism is discussed. Multi-color tunable blue, white, yellow, and green emission lights due to the Ce<SUP>3+</SUP> and Mn<SUP>2+</SUP> emitters were observed at room temperature. With these phosphors, the desired CIE values including emissions throughout multi–color regions of the spectra were achieved.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ce<SUP>3+</SUP>–Mn<SUP>2+</SUP>–doped Y<SUB>7</SUB>O<SUB>6</SUB>F<SUB>9</SUB> vernier phosphors were prepared. </LI> <LI> Effective PL spectra of the phosphors were clearly monitored. </LI> <LI> High energy transfer from Ce<SUP>3+</SUP> to Mn<SUP>2+</SUP> was analyzed. </LI> <LI> Tunable multi–color emissions of the spectra were achieved. </LI> </UL> </P>