• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.199-200
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• 2015

실리콘 기판위에 Gecko의 피부를 모사한 다층의 나노, 마이크로 구조표면에서 일어나는 응결된 water vapor droplets의 coalescence에 기인하는 surface energy의 kinetic energy의 변환을 통하여 발생하는 water droplets의 self-propelling을 이용한 빙점하에서 dynamic wetting 성질의 관찰을 통해서 얼음 방지, 지연, 또는 얼음 부착성 최소화 표면의 구현 가능성을 보여준다.

• 한국가스학회:학술대회논문집
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• 2006.11a
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• pp.196-199
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• 2006

• Journal of the Korean Wood Science and Technology
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• v.21 no.1
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• pp.51-58
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• 1993

The phenol resorcinol formaldehyde resin (PRF) adhesives which are curing at ambient temperature for structural purposes were synthesized. A PRF resin is produced according to the two-stage reaction system. In first stage, a low-condensed resol or methylolated phenol were prepared from phenol by reaction with a formaldehyde in alkaline condition. The molar ratio of phenol to formaldehyde was 1.0~1.4. And in second-stage, resorcinol was added to combine with the methylol group of a low-condensed resol(R/P molar ratio 0.3). The glue-joint strength, pot-life and workability of this synthetic PRF resin were superior to conventional ambient temperature setting adhesives such as oilic urethane or water based polymer-isocyanate resin for wood adhesives.

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.2 s.13
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• pp.53-59
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• 2004

The mechanism of manhole bursting which occurs at excess rainfall events Is studied by using both the physical model and the numerical model (SWMM ; Storm Water Management Model). The result of numerical simulation to steep pressure rising agrees well with that of the physical model at the sewer system under surcharged flow. A cause of manhole bursting is an expansion and spout of the condensed all at manhole that results from the surcharged flow and press wave propagation caused by gate operation or closure of conduit at pumping station.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1638-1649
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• 2020

In the case of a severe accident in a Light Water Reactor, the issue of late release of fission products, from the primary circuit surfaces is of particular concern due to the direct impact on the source term. CsI is the main iodine compound present in the primary circuit and can be deposited as particles or condensed species. Its chemistry can be affected by the presence of molybdenum, and can lead to the formation of gaseous iodine. The present work studied chemical reactions on the surfaces involving gaseous iodine release. CsI and MoO₃ were used to highlight the effects of carrier gas composition and oxygen partial pressure on the reactions. The results revealed a noticeable effect of the presence of molybdenum on the formation of gaseous iodine, mainly identified as molecular iodine. In addition, the oxygen partial pressure prevailing in the studied conditions was an influential parameter in the reaction.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1397-1405
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• 2009

In recent decades, exergy analysis has been holding spotlight as a useful tool in the design, assessment, optimization, and improvement of energy system. This paper presents the results of the energy and exergy analysis of a steam turbine cogeneration system for industrial complex using two efficiency concepts of conventional one and exergetic one. In order to obtain the destroyed exergy of each component, mathematical analysis is conducted by using exergy balance and the second law of thermodynamics, according as the parameters are changed, such as the ratio of returned process steam, process steam supplied, temperature and pressure of boiler and power. The computer program developed in this study can determine the efficiencies and exergy destroyed at each component of cogeneration system. As a result of this study, a component having the largest destroyed exergy was boiler. And closed and opened feedwater heater had the lowest one. The affects to the cogeneration system due to the variation of process steam flow and return rate of condensed water is shown that the total electric power efficiency(${\eta}_E$) is decreased as increasing the return rate of condensed water under constant process steam flow. As the boiler pressure is increased for the more production of electricity, the efficiency of cogeneration system was decreased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.427-434
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• 2020

This study was conducted to investigate the effects of dietary supplementation with condensed molasses soluble (CMS), which has economically benefitted as an alternative ingredient of molasses, on growth performance and meat quality in growing-finishing pigs. A total of 160 cross-bred growing pigs (LY×D) having body weight 27.3±1.78 kg, were allotted to 1 of the 4 treatment groups with 4 replications each, in a completely random block design. The experimental diet consisted of a basal diet (CON), with supplementation of molasses 3% (MOL 3.0), CMS 1.5% (CMS 1.5), and CMS 3% (CMS 3.0) to basal diet. Feed and water were provided ad libitum for 70 days. We observed higher feed intake in the MOL 1.5, CMS 1.5, and CMS 3.0 groups than CON group. The final body weight and weight gain were significantly improved in the CMS 3.0 group (p<0.05), as compared to CON group. Evaluation of the meat quality revealed no significant difference in water holding capacity, heating loss, and pH, among all experiment groups. This study indicates that feeding CMS results in improved growth performance in growing-finishing pigs without deterioration in meat quality, and has the potential to be used as an alternative ingredient of molasses in swine feed.

• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.91-100
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• 1996

Condensed ethyl silicate(CES) solutions were prepared from $SiCl_4$ and ethanol which is different in water content(2.5, 5.0 and 7.0wt.% ). To investigate the sol-gel transition behaviors of CES and PHT(partially hydrolyzed TEOS) solutions, the measurement of volume change, density, $SiO_2$ content, intrinsic viscosity and number average molecular weight were conducted with elapsed time. The polymer shapes of CES were discussed from the relation between the intrinsic viscosity[$\eta$] and the number average molecular weight($\bar{Mn}$). CES-3 prepared from ethanol containing 7.0wt.% $H_2O$ had different sol-gel transition behaviors from CES-1 (2.5wt.% $H_2O$) and CES-2(5.Owt.% $H_2O$), but similar behaviors to those of PHT which is used for controlling the hydrolysis rata of TEOS when composite ceramic materials were manufactured from silicon alkoxides. On the basis of Mark-Hawink relation, $[{\eta}]=K\bar{Mn}^{{\alpha}}$, the polymer shape of CES solutions were determined linear siloxane polymers because all solutions had ${\alpha}$ values in the range from 0.53 to 0.84. Especially, CES-3 showed to be a favorable raw materials for composite ceramics due to its similar properties to those of PHT.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.46-53
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• 2011

Water is continuously produced in polymer electrolyte membrane fuel cell (PEMFC), and is transported and exhausted through polymer electrolyte membrane (PEM), catalyst layer (CL), microporous layer (MPL), and gas diffusion layer (GDL). The low operation temperatures of PEMFC lead to the condensation of water, and the condensed water hinders the transport of reactants in porous layers (MPL and GDL). Thus, water flooding is currently one of hot issues that should be solved to achieve higher performance of PEMFC. This research aims to study liquid water transport in porous layers of PEMFC by using pore-network model, while the microscale pore structure and hydrophilic/hydrophobic surface properties of GDL and MPL were fully considered.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.1
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• pp.177-185
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• 2020

Objective: The study was conducted to establish a relationship between inclusion level of Vachellia tortilis (V. tortilis) leaf meal and time spent on different behavioral activities by finishing pigs. Methods: A total of forty-eight male Large White×Landrace finishing pigs with a mean (±standard deviation) body weight of 63.8±3.28 kg aged 14 wks were assigned to individual pens in a completely randomized design. Pigs were fed on diets containing 0, 30, 60, 90, 120, and 150 g/kg dry matter of V. tortilis leaf meal ad libitum with fresh water provided throughout the trial. There were eight pigs in each experimental diet. The behavior of pigs was observed for three wks twice a wk from 0600 to 1800 h using six closed circuit television cameras. Results: Increasing levels of V. tortilis leaf meal caused a linear decrease (p<0.05) in time spent eating, lying down and the number of visit to the feeder. Time spent standing and biting objects increased linearly (p<0.05) with increasing inclusion level of V. tortilis leaf meal. The was a negative linear relationship (p<0.05) between condensed tannins versus time spent eating, lying down and number of feeder visits. Condensed tannins showed a positive linear relationship (p<0.05) with time spent standing and biting objects. Neutral detergent fiber caused a linear decrease (p<0.05) in number of feeder visits, time spent eating, time spent standing. Conclusion: Inclusion level of V. tortilis leaf meal reduces time spent eating, lying down and the number of feeder visit while prolonging time spent standing and biting of objects. Condensed tannins and dietary fiber are among nutritional factors affecting behavioral activities displayed by finishing pigs.