• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.2
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• pp.265-270
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• 1989

The present study considers the thermal structure variation in a porous medium caused by changing the most important radiative property of porous medium, absorption coefficient, as well as altering the physical dimension of porous medium and the equivalence ratio of premixed gas mixture. The radiation model was introduced as an unsteady differential form using the two-flux gray radiation model. The role of the conductive heat transfer through both gas phase and porous medium was found to be almost insignificant compared with that of the radiative heat transfer. The reaction zone shifted upstream and the flame thickness decreased as either the geometrical length of porous medium increased or the absorption coefficient decreased.

• Journal of the Korean Wood Science and Technology
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• v.43 no.2
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• pp.206-213
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• 2015

This study was carried out to use carbonized medium density fiberboard (MDF) for the replacement of sound absorbing material. Carbonization treatment was performed to improve sound absorption property for MDF at carbonizing temperatures of $500^{\circ}C$, $700^{\circ}C$, $900^{\circ}C$ and $1100^{\circ}C$. As the carbonization temperature increased, the results of the observation by scanning electron microscope (SEM) demonstrated that the fibers exhibited a more compressed morphology within the surface section of the MDF than those within the middle section of MDF. As the carbonizing temperature increased, the cavity increased. The sound absorption coefficient increased between the temperatures of $500^{\circ}C$ and $900^{\circ}C$, but decreased at a temperature of $1100^{\circ}C$. The sound absorption properties of the carbonized MDF and the non-carbonized MDF were compared. The maximum sound absorption coefficient of the carbonized MDF was 12.38%. This was almost double of the value of the non-carbonized MDF.

• Journal of Pharmaceutical Investigation
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• v.27 no.3
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• pp.189-198
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• 1997

The purpose of the present study was to investigate the effect of medium chain fatty acid salts, reported as enhancers in insulin nasal absorption, on the rectal absorption of insulin in rats. The serum glucose and remained insulin level in perfusate were measured after rectal recirculation of insulin with or without sod. laurate, sod. caprate and sod. caprylate in situ. The addition of sod. laurate or sod. caprate reduced serum glucose concentration considerably. Sod. caprate (1.0%) showed the greatest promoting effect on the decrement of serum glucose. Eudispert hv hydrogels containing insulin with medium chain fatty acid salts were, thereby, prepared and evaluated. The release rate of insulin from Eudispert hv hydrogels was reduced with an increase in the content of Eudispert hv, and was raised with increasing NaOH concentration. Ten percent Eudispert hv hydrogels were offered for the rectal administration of insulin. The addition of 1.0% sod. caprate reduced serum glucose concentration remarkably after rectal administration of 10% Eudispert hv hydrogels containing insulin. The level of glucose decrement was greater by 30% compared to subcutaneous administration of insulin solution. From the above findings, Eudispert hv hydrogels would be used as useful rectal delivery systems of insulin.

• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.555-562
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• 2014

Characteristics of carbonized fiberboard such as chemical materials absorption, electromagnetic shielding, and electrical and mechanical performance were determined in previous studies. The carbonized board therefore confirmed that having excellent abilities of these characteristics. In this study, the effect of density on physical properties and sound absorption properties of carbonized fiberboards at $800^{\circ}C$ were investigated for the potential use of carbonized fiberboards as a replacement of conventional sound absorbing material. The thickness of fiberboards after carbonization was reduced 49.9%, 40.7%, and 43.3% in low density fiberboard (LDF), medium density fiberboard (MDF), and high density fiberboard (HDF), respectively. Based on SEM images, porosity of carbonized fiberboard increased by carbonization due to removing adhesives. Moreover, carbonization did not destroy structure of wood fiber based on SEM results. Carbonization process influenced contraction of fiberboard. The sound absorption coefficient of carbonized low density fiberboard (c-LDF) was higher than those of carbonized medium density fiberboard (c-MDF) and carbonized high density fiberboard (c-HDF). This result was similar with original fiberboards, which indicated sound absorbing ability was not significantly changed by carbonization compared to that of original fiberboards. Therefore, the sound absorbing coefficient may depend on source, texture, and density of fiberboard rather than carbonization.

• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.615-623
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• 2014

Increases of public attention on healthy environment lead to the regulation of indoor air quality such as Clean Healthy House Construction Standard. This standard covers emission of total volatile organic compounds (TVOCs) (e.g., formaldehyde, benzene, and toluene), ventilation, and use of environmentally-friendly products or functional products. Moisture absorption and desorption abilities are a recommended functionality for improving indoor air quality. In this study, moisture absorption and desorption capacities of carbonized board from wood-based panels and other materials were determined by using UNT-HEAT-01 according to ISO 24358:2008. Pine had higher moisture absorption and desorption capacities ($49.0g/m^2$ and $35.3g/m^2$, respectively) than hinoki cypress, cement board, gypsum board, oriented strand board, and medium density fiberboard (MDF). The moisture absorption and desorption capacities differed considerably according to the wood species. After carbonization process at $400^{\circ}C$, the absorption and desorption ability of MDF increased to 38% and 60%, respectively. However, moisture absorption and desorption capacities decreased with increasing carbonization temperature, but they were still higher than original MDF. Therefore, it is suggested that carbonization below $600^{\circ}C$ can improve moisture absorption/desorption capacities.

• Bulletin of the Korean Chemical Society
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• v.16 no.12
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• pp.1184-1189
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• 1995

The rapid quenching dynamics of F center excitation by OH- defects in KCl crystals are investigated by monitoring ground state absorption bleach recovery, using a picosecond streak camera absorption spectrometer. F center absorption bleach in OH--doped crystals shows three distinguishable recovery components with the current temporal resolution, designated as slow, medium and fast components. The slow one is due to the normal relaxation process of F* centers as found in OH--free crystals. The others are consequent on energy transfer from electronically excited F centers to OH--vibrational levels. The fast component is a minor energy transfer process and resulting from the relaxation of somewhat distant, not the closest, associated pairs of F* and OH- defects. The energy transfer between widely separated F* and OH- defects opens up a recovery process via the medium component which is assisted by OH- librations, lattice vibrations and OH- dipole reorientations. The quenching behaviors of F* luminescence and photoionization by OH- are explained well by the relaxation process of the medium component.

• Nuclear Engineering and Technology
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• v.50 no.3
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• pp.389-395
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• 2018

The present work aims to report the consequences of Darcy-Forchheimer medium in flow of Cross fluid model toward a stretched surface. Flow in porous space is categorized by Darcy-Forchheimer medium. Further heat transfer characteristics are examined via thermal radiation and heat generation/absorption. Transformation procedure is used. The arising system of nonlinear ordinary differential equations is solved numerically by means of shooting method. The effects of different flow variables on velocity, temperature, concentration, skin friction, and heat transfer rate are discussed. The obtained outcomes show that velocity was enhanced with the increase in the Weissenberg number but decays with increase in the porosity parameter and Hartman number. Temperature field is boosted by thermal radiation and heat generation; however, it decays with the increase in the Prandtl number.

• Journal of Nutrition and Health
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• v.29 no.6
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• pp.578-589
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• 1996

This study was performed to invstigate the effect of dietary protein level and source on cadmium intoxicification in rats. Forty-eight male rats of Sprague-Dawley strain weighing 171$\pm$3g were blocked into 8 groups of 6 animals according to body weigth, and were raised for 30days. Eight experimental diets different with cadmium(0ppm, 400ppm)and protein(15%, 40%) levels and protein source[casien, I.S.P.(isolated soy protein)] were given to animals for 30days. Food intake, weight gain, food efficiency ratio, liver weight, kidney weight and femur weight were lower in cadmium added group, and higher in high protein groups(40% protein) than medium protein groups(15% protein). But, dietary protein source had no influence on them. Cadmium concerntration of liver was higher in rats fed casein than I.S.P. groups, and cadmium concentration in intestine was higher in high protein groups. In femur both high protein and I.S.P.diets increased cadmium concentrations. MT concdentrations in liver, kidney and intestine were higher in cadmium added group, and kidney intestine MT concentration were higher in high protein group. Absorption and retention rates of cadmium were lower in rat fed I.S.P. than animal fed casein among medium protein groups and cadmium concentration in blood and liver of I.S.P groups were lower than casein groups. But absorption and retention rates of cadmium were similar in high casein and I.S.P. groups. Renal damage by cadmium administration was not seen in all groups. Absorption rates of zinc and copper competing with cadmium in absorption process were lower in high protein groups than medium protein groups and lower in rats fed I.S.P. than casein. In conclusion, weight gain, F.E.R, and MT concentraion of high protein groups were higher than those of medium protein groups and absorption and retention rates of cadmium were lower in high protein groups. From these results, it was shown that cadmium toxicity was alleviated by high dietary protein. Meanwhile, the effect of dietary source on the cadmium toxicity was different with protein level. In medium protein groups absorption and retention rates of cadmium were much lower in rats fed I.S.P. than casein. In high protein groups, cadmium toxicity was not influenced by protein source and absorption and retention rates of cadmium were not different between casein and I.S.P. groups.

• Journal of Convergence for Information Technology
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• v.9 no.7
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• pp.67-77
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• 2019

Many small and medium-sized enterprises are deploying Smart Factory without due consideration of the circumstances in which the entity is in or outside of the entity, such as environmental changes and the capabilities of its members. Therefore, utilization and effectiveness are also low after deployment. This study verifies 'the establishment of a Smart Factory through the environmental factors and absorption capabilities of small businesses' through empirical research. The survey was received by people working for small and medium-sized companies that have established Smart Factory. The results of the study showed that first, environmental factors within and outside the company had a positive effect on the absorption capacity within the company. Second, the absorption capacity within a company has had a positive effect on the deployment of a Smart Factory. Based on the above proof, it has been proved to be effective if the core areas of the Smart Factory are built on the basis of the company's internal and external environmental factors and absorption capabilities when constructing Smart Factory in small businesses. In the future, we will study the achievements of smart factory construction.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.9
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• pp.143-156
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• 2022

This article examines the effect of inward foreign direct investments (FDI) on the export performance of micro, small & medium enterprises (MSMEs) in India, and investigates the spillover impact and absorption capacity of the MSMEs sector. For the first time, the researchers applied the intersectoral linkage approach to investigate the matter and used a panel dataset between 2006 and 2017. The coefficients of forward and backward linkages are estimated by using the Rasmussen method, the study employs a basic linear panel data model, followed by various diagnostic tests to identify the problem of heteroscedasticity, autocorrelation / serial correlation, cross-sectional dependencies, multicollinearity, time-individual specific tests, and unobserved effects. The PCSE model was applied for robust standard error and the Hausman-Taylor IV model to check the robustness of the result generated in the linear panel data model. Despite the high prevalence of forward and backward intersectoral connections and the Lack of absorption capacity of local firms, the results show that FDI has little of an impact on the export performance of micro, small, and medium-sized businesses in India. This study adds to the existing literature on determining local firms' spillover effect and absorption capacity in response to inward FDI.