• Membrane and Water Treatment
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• v.3 no.4
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• pp.231-242
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• 2012

The performance of a nanofiltration membrane for treatment of a low-level radioactive liquid waste was investigated through static and dynamic tests. The liquid waste ("carbonated water") was obtained during conversion of $UF_6$ to $UO_2$. In the static tests membrane samples were immersed in the waste for 24, 48 or 72 h. The transport properties of the samples (hydraulic permeability, permeate flow, selectivity) were evaluated before and after immersion in the waste. In the dynamic tests the waste was permeated in a permeation flow front system under 0.5 MPa, to determine the selectivity of NF membranes to uranium. The surface layer of the membrane was characterized by zeta potential, field emission microscopy, atomic force spectroscopy and infrared spectroscopy. The static test showed that the pore size distribution of the selective layer was altered, but the membrane surface charge was not significantly changed. 99% of uranium was rejected after the dynamic tests.

• Advances in Computational Design
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• v.7 no.2
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• pp.99-112
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• 2022

This research has been devoted to examine nonlinear static bending analysis of smart beams with nano dimension exposed to thermal environment. The beam elastic properties are corresponding to piezo-magnetic material of different compositions. The large deflection analysis of the beam has been performed assuming that the beam is exposed to transverse uniform pressure. Based on the rule of Hamilton, the governing equations have been derived for a nonlocal thin beam and solved using differential quadrature method. Temperature variation effect on nonlinear deflection of the smart beams has been studied. Also, the beam deflection is shown to be affected by electric voltage, magnetic intensity and material composition.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3615-3620
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• 2010

This study is development of UV-cured coating compounds which has more improved anti-stain and anti-biosis, about surface prevention of PVC Tile. We added water-soluble anti-static and anti-microbial agent to the resin. The process has prevented electrostatic and bacterial contagious disease. The result, which added 15wt% of water-soluble anti-static and 1wt% anti-microbial agent and coated with No.12 Bar-coater, coating composition had optimum surface property. It appear electric resistance($10^9{\Omega}/cm^2$), anti-stain (Ink Test, Dust Test), anti-biosis (99.99%), and adhesive power(100%).

• Geomechanics and Engineering
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• v.29 no.2
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• pp.99-111
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• 2022

Instability of bolted rock mass has been a major hazard in the underground coal mining industry for decades. Developing effective support guidelines requires understanding of complex bolted rock mass failure mechanisms. In this study, the dynamic failure behavior, mechanical behavior, and energy evolution of a laboratory-scale bolted specimens is studied by conducting laboratory static-dynamic coupled loading tests. The results showed that: (1) Under static-dynamic coupled loading, the stress-strain curve of the bolted rock mass has a significant impact velocity (strain rate) correlation, and the stress-strain curve shows rebound characteristics after the peak; (2) There is a critical strain rate in a rock mass under static-dynamic coupled loading, and it decreases exponentially with increasing pre-static load level. Bolting can significantly improve the critical strain rate of a rock mass; (3) Compared with a no-bolt rock mass, the dissipation energy ratio of the bolted rock mass decreases exponentially with increasing pre-static load level, the ultimate dynamic impact energy and dissipation energy of the bolted rock mass increase significantly, and the increasing index of the ratio of dissipation energy increases linearly with the pre-static load; (4) Based on laboratory testing and on-site microseismic and stress monitoring, a design method is proposed for a roadway bolt support against dynamic load disturbance, which provides guidance for the design of deep underground roadway anchorage supports. The research results provide new ideas for explaining the failure behavior of anchorage supports and adopting reasonable design and construction practices.

• The Korean Journal of Nuclear Medicine Technology
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• v.20 no.2
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• pp.36-41
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• 2016

Purpose Sentinel lymphoscintigraphy (SLS) was using only $^{99m}Tc-phytate$. If the supply is interrupted temporarily, there is no alternative radiopharmaceuticals. The aim of this study measure the particle size of radiopharmaceuticals and look for radiopharmaceuticals which can be substituted for $^{99m}Tc-phytate$. Materials and Methods The particle size of radiopharmaceuticals were analyzed by a nano-particle analyzer. This study were selected known radiopharmaceuticals to be useful particle size for SLS. We were divided into control and experimental groups using $^{99m}Tc-DPD$, $^{99m}Tc-MAG3$, $^{99m}Tc-DMSA$ with $^{99m}Tc-phytate$. For in-vivo experiment, radiopharmaceuticals were injected intradermally at both foot to perform lymphoscintigraphy. Imaging was acquired to dynamic and delayed static image and observe the inguinal lymph nodes with the naked eye. Results Particle size was measured respectively Phytate 105~255 nm (81.9%), MAG3 91~255 nm (98.7%), DPD 105~342 nm (77.3%), DMSA 164~ 342 nm (99.2%), MAA 1281~2305 nm (90.6%), DTPA 342~1106 nm (79.4%), and HDP 295~955 nm (94%). In-vivo delayed static image, inguinal lymph nodes of all experiment groups and two control groups are visible to naked eye. however, $^{99m}Tc-MAG3$ of control groups is not visible to naked eye. Conclusion We were analyzed to the particle size of the radiopharmaceuticals that are used in in-vivo. Consequently, $^{99m}Tc-DPD$, $^{99m}Tc-DMSA $are possible in an alternative radiopharmaceuticals of emergency.

• Geomechanics and Engineering
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• v.25 no.2
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• pp.99-109
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• 2021

Tunnel provide faster, safer and convenient way of transportation for different objects. The region where it is construction and surrounding medium has significant influence on the overall stability and performance of tunnel. The present simulation has been carried out in order to understand the behaviour of rock tunnel under static loading condition. The present numerical model has been validated with the laboratory scaled model and field data of underground tunnels. Both lined and unlined tunnels have been considered in this paper. Finite element technique has been considered for the simulation of static loading effect on tunnel through Abaqus/Standard. The Mohr-Coulomb material model has been considered to simulate elastoplastic nonlinear behaviour of different rock types, i.e., Basalt, Granite and Quartzite. The four different stages of rock weathering are classified as fresh, slightly, moderately, and highly weathered in case of each rock type. Moreover, extremely weathered stage has been considered in case of Quartzite rock. It has been concluded that weathering of rock and overburden depth has great influence on the tunnel stability. However, by considering a particular weathering stage of rock for each rock type shows varying patterns of deformations in tunnel.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.4
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• pp.545-552
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• 2015

The main object of this study is to investigate the collection characteristics of an electro-static multi-staged impaction system, experimentally. The experiment is carried out to analyze the characteristics of pressure drop and collection efficiency for the present system with the experimental parameters such as the inlet velocity, stage number, applied voltage and shape of discharge electrode, etc. In results, the pressure drop is shown below $148mmH_2O$ lower than that of the conventional bag filter at inlet velocity 3.46 m/s and 5 stage. For 5 stage, the collection efficiencies are to be 97.4, 99.0% with the applied voltage 0 kV at the inlet velocity 2.07, 3.46 m/s, while 98.4, 99.9% with 40 kV of a sharp edge discharge electrode. Additionally, the present system is to be considered as an effective compact system for a removal of particulate pollutants from marine diesel engines due to much higher collection efficiency and appropriate pressure drop.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.326-331
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• 2019

In the real world, there are both dynamic objects and static objects, but an autonomous vehicle or mobile robot cannot distinguish between them, even though a human can distinguish them easily. It is important to distinguish static objects from dynamic objects clearly to perform autonomous driving successfully and stably for an autonomous vehicle or mobile robot. To do this, various sensor systems can be used, like cameras and LiDAR. Stereo camera images are used often for autonomous driving. The stereo camera images can be used in object recognition areas like object segmentation, classification, and tracking, as well as navigation areas like 3D world reconstruction. This study suggests a method to distinguish static/dynamic objects using stereo vision for an online autonomous vehicle and mobile robot. The method was applied to a 3D world map reconstructed from stereo vision for navigation and had 99.81% accuracy.

• Nuclear Engineering and Technology
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• v.37 no.4
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• pp.391-394
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• 2005

N-(3-bromo-2,4,6-trimethylacetanilide)iminodiacetic acid (BrTIDA) was synthesized using nitrilotriacetic anhydride prepared in situ, and lyophilized vials were prepared which contained 20 mg of BrTIDA and 0.4 mg of $SnCl_2$. To evaluate the clinical efficacy of the in-house prepared lyophilized kit, a technetium-99m complex of BrTIDA was prepared; its in vivo pharmacokinetic behavior was evaluated via animal studies to assess the hepatocytic function and the functional status of the cystic duct and the gallbladder. Serial static image scans of rabbits and the biodistribution in mice injected with $^{99m}Tc-BrTIDA$ revealed that none of the tissues except for the hepatobiliary system showed radioactivity concentrations, and a rapid clearance from the organs was observed. In conclusion, a lyophilized kit and its prepared $^{99m}Tc-BrTIDA$ can be applied as a hepatobiliary imaging agent for the evaluation of the functional status of the hepatocytes and the patency of the biliary duct.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.15-21
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• 2004

This paper describes the development of $^{99m}Tc$ tricarbonyl cysteine as potential renal function diagnostic radiopharmaceutical and evaluation of its biological characteristics using experimental animals. l-Cysteine was labeled efficiently with $^{99m}Tc$ tricarbonyl precursor $([^{99m}Tc(CO)_3(H_2O)_3)]^{+})$ under 30 min heating at ${75^{\circ}C}$. Labeling yield and stability were analyzed by high performance liquid chromatography (HPLC). The biodistribution property of $^{99m}Tc$ tricarbonyl cysteine in mice and its dynamic imaging profiles in rabbits were carried out. To investigate the excretion mechanism of $^{99m}Tc$ tricarbonyl cysteine, tubular transport inhibition test with probenecid was adopted. $^{99m}Tc$ tricarbonyl cysteine was obtained with a high labeling yield under the moderate condition. The results of biodistribution experiments of $^{99m}Tc$ tricarbonyl cysteine in ICR mice at 3 and 90 min provided that $^{99m}Tc$ tricarbonyl cysteine was very highly accumulated in the kidney and bladder, thereby almost 99% of $^{99m}Tc$ tricarbonyl cysteine was excreted within 90 min post injection. The same results were confirmed by the whole body dynamic images for 30 minutes and static images in rabbits at given time intervals after injection. Renogram of $^{99m}Tc$ tricarbonyl cysteine in rabbits showed that its $T_{max}$ and $T_{1/2}$ of $^{99m}Tc$ tricarbonyl cysteine were $2.33{\pm}0.56$ and $4.30{\pm}0.79$ min, respectively. The $T_{max}$ of $^{99m}Tc$ tricarbonyl cysteine with probenecid pretreatment was $2.30{\pm}0.17$ min, whereas $T_{1/2}$ of that with probenecid pretreatment was $17.0{\pm}32.47$ min. $T_{1/2}$ of $^{99m}Tc$ tricarbonyl cysteine with probenecid pretreatment was significantly different, as compared to the result without probenecid (p<0.0001). The results showed that the excretion of $^{99m}Tc$ tricarbonyl cysteine was extremely affected by probenecid. Therefore, $^{99m}Tc$ tricarbonyl cysteine was rapidly excreted from the kidney principally by the tubular secretion.