• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.4
• /
• pp.639-647
• /
• 2019

Recently, as the semiconductor integration technology due to miniaturization and high density of electronic equipment have developed, it is importantly recognized the application of thermal control system in order to release inner heat generated from chips, modules, In this study, we considered the heat transfer and pressure drop characteristics in a horizontal channel with four blocks using k-${\omega}$ SST turbulence model During CFD (Computational Fluid Dynamics) analysis, the parameters applied block width, block height, heat source and turbulence generator placement etc. As the boundary conditions of analysis, the channel inlet temperature and flow velocity were respectively 300 K and 3.84 m/s, the heat flux was $358W/m^2$. As a result, the heat transfer performance was decreased as the block width ratio (w/h) was increased, while it was increased as the block height ratio (h/w) was increased. In addition, as the arrangement of heat source size was increased to high heat flux from low heat flux, it was influenced by heat source size and the heat transfer coefficient showed a tendency to increase, When the turbulence generator was installed in the upper part of block No. 1 position the closely to the channel entrance, the heat transfer characteristics was greatly influenced on the whole of four heating blocks. and in oder to consider the pressure drop characteristics, we are able to select the most appropriate turbulence generator's position.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.17 no.1
• /
• pp.29-36
• /
• 2019

High-level radioactive waste (HLW) such as spent fuel is inevitably produced when nuclear power plants are operated. A geological repository has been considered as one of the most adequate options for the disposal of HLW, and it will be constructed in host rock at a depth of 500~1,000 meters below ground level with the concept of an engineered barrier system (EBS) and a natural barrier system. The compacted bentonite buffer is one of the most important components of the EBS. As the compacted bentonite buffer is located between disposal canisters with spent fuel and the host rock, it can restrain the release of radionuclides and protect canisters from the inflow of groundwater. Because of inflow of groundwater into the compacted bentonite buffer, it is essential to investigate soil-water characteristic curves (SWCC) of the compacted bentonite buffer in order to evaluate the entire safety performance of the EBS. Therefore, this paper conducted laboratory experiments to analyze the SWCC for a Korean Ca-type compacted bentonite buffer considering dry density, confined or unconfined condition, and drying or wetting path. There was no significant difference of SWCC considering dry density under unconfined condition. Furthermore, it was found that there was higher water suction in unconfined condition that in confined condition, and higher water suction during drying path than during wetting path.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.37 no.2
• /
• pp.61-72
• /
• 2021

A beautiful smile is made when it is symmetrical and gums are displayed less than 2 - 3 mm. Excessive gingival display also known as "gummy smile" is often recognized to be unaesthetic. Causes of gummy smile can be caused by delayed eruption, vertical maxillary excess, hypermobile upper lip, or a short upper lip. Meanwhile botulinum toxin which is an exotoxin produced from Clostridium botulinum, works by blocking the release of acetylcholine from the cholinergic nerve end plates leading to inactivity of the muscles. The application site and weakens the muscle tone is drawing attention as a gummy smile treatment caused by hypermobile upper lip. There have been many studies about the method of injecting botulinum toxin into muscles around the lips, but there is still no standardized research method and treatment method, so there is controversy over the therapeutic effect. The aim of this study is to review the previous studies about the predictors of indication and effects of gummy smile treatment using botulinum toxin injection. Especially we tried to propose a protocol for optimal dose and efficient injection point through the anatomical considerations for gummy smile treatment using botulinum toxin.

• Journal of Ginseng Research
• /
• v.45 no.2
• /
• pp.228-235
• /
• 2021

Backgroud: Ginsenoside compound K (GK) is a major metabolite of protopanaxadiol-type ginsenosides and has remarkable anticancer activities in vitro and in vivo. This work used an ionic cross-linking method to entrap GK within O-carboxymethyl chitosan (OCMC) nanoparticles (Nps) to form GK-loaded OCMC Nps (GK-OCMC Nps), which enhance the aqueous solubility and stability of GK. Methods: The GK-OCMC Nps were characterized using several physicochemical techniques, including x-ray diffraction, transmission electron microscopy, zeta potential analysis, and particle size analysis via dynamic light scattering. GK was released from GK-OCMC Nps and was conducted using the dialysis bag diffusion method. The effects of GK and GK-OCMC Nps on PC3 cell viability were measured by using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Fluorescent technology based on Cy5.5-labeled probes was used to explore the cellular uptake of GK-OCMC Nps. Results: The GK-OCMC NPs had a suitable particle size and zeta potential; they were spherical with good dispersion. In vitro drug release from GK-OCMC NPs was pH dependent. Moreover, the in vitro cytotoxicity study and cellular uptake assays indicated that the GK-OCMC Nps significantly enhanced the cytotoxicity and cellular uptake of GK toward the PC3 cells. GK-OCMC Nps also significantly promoted the activities of both caspase-3 and caspase-9. Conclusion: GK-OCMC Nps are potential nanocarriers for delivering hydrophobic drugs, thereby enhancing water solubility and permeability and improving the antiproliferative effects of GK.

• Journal of Nutrition and Health
• /
• v.55 no.3
• /
• pp.348-358
• /
• 2022

Purpose: Hyperglycemia accelerates the formation of advanced glycation end products (AGEs), a group of compounds formed via non-enzymatic glycation/glycoxidation. Type 2 diabetes mellitus (T2DM) is related to oxidative stress, resulting in some overgeneration of AGEs. The accumulation of AGEs in T2DM patients leads to increased inflammation, DNA damage, tissue damage, progression of diabetic microvascular disease, and nephropathy. Heme oxygenase-1 (HO-1) is an intracellular enzyme that catalyzes the oxidation of heme. Expression of HO-1 in the endothelium and in muscle monocytes/macrophages was upregulated upon exposure to reactive oxygen species or oxidized low-density lipoprotein. Cells activated by oxidative stress are reported to release HO-1 in the serum. In the current study, we discuss the oxidative status according to the level of AGEs and the association of HO-1 with AGEs or urinary DNA damage marker in type 2 diabetic Korean patients. Methods: This study enrolled 36 diabetic patients. Subjects were classified into two groups by serum AGEs level (Low AGEs group: < 0.85 ng/mL serum AGEs; High AGEs group: ≥ 0.85 ng/mL serum AGEs). Body composition was measured using bioelectrical impedance analysis. Blood and urinary parameters were measured using commercial kits. Results: No significant differences were observed in the general characteristics and body composition between the two groups. Serum HO-1 concentration was significantly higher in the High AGEs group than in the Low AGEs group. After adjustment of age and gender, a correlation was performed to assess the association between serum HO-1 and serum AGEs or urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG). Our results indicate that serum HO-1 is positively correlated with serum AGEs and urinary 8-OHdG. Conclusion: Taken together, our results indicate that in diabetes patients, a high level of HO-1 is associated with a high concentration of AGEs and 8-OHdG, probably reflecting a protective response against oxidative stress.

• Journal of the Korean Institute of Gas
• /
• v.26 no.3
• /
• pp.27-37
• /
• 2022

With the recent increase in the spread of ESS (Electric Storage System), the damage to human life and property is also rapidly increasing due to continuous fires caused by ESS. In the manufacture of urethane sandwich panels used in ESS, it is necessary to improve the flame retardant performance. In this study, in order to realize the flame retardant properties of flexible polyurethane foam, the effect of the tissue density of the product due to the change of the isocyanate functional group parameter that changes the physical properties of the product on the fire performance was studied. The product was manufactured by changing the density of the urethane structure, and combustion performance tests, gas toxicity tests, and smoke density tests were performed. As a result, it was confirmed that the total amount of heat released had excellent performance when the isocyanate functional group was high, and had no correlation with the maximum heat release rate. When the value of the isocyanate functional group was 2.7 or more, the collapse of the shape could be prevented. In the gas hazard test, the performance was increased when the isocyanate functional group was relatively high, so a flame retardant for the Char system, which had a dense structure and easy to form a carbonized film, was added. confirmed to be. Therefore, as a result of this study, it is thought that it will be possible to lay the foundation for the development of a flame retardant to replace the cheap urethane sandwich panel used in the past.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.22 no.3
• /
• pp.217-226
• /
• 2022

Background: Intraosseous anesthesia is the process by which an anesthetic solution, after penetration of the cortical bone, is directly injected into the spongiosa of the alveolar bone supporting the tooth. This study aimed to compare the effectiveness of the traditional inferior alveolar nerve block (IANB) and computerized intraosseous anesthesia in the surgical extraction of impacted lower third molars, compare their side effects systemically by monitoring heart rate, and assess patients' a posteriori preference of one technique over the other. Methods: Thirty-nine patients with bilaterally impacted third molars participated in this study. Each patient in the sample was both a case and control, where the conventional technique was randomly assigned to one side (group 1) and the alternative method to the contralateral side (group 2). Results: The traditional technique was faster in execution than anesthesia delivered via electronic syringe, which took 3 min to be administered. However, it was necessary to wait for an average of 6 ± 4 min from the execution to achieve the onset of IANB, while the latency of intraosseous anesthesia was zero. Vincent's sign and lingual nerve anesthesia occurred in 100% of cases in group 1. In group 2, Vincent's sign was recorded in 13% of cases and lingual anesthesia in four cases. The average duration of the perceived anesthetic effect was 192 ± 68 min in group 1 and 127 ± 75 min in group 2 (P < 0.001). The difference between the heart rate of group 1 and group 2 was statistically significant. During infiltration in group 1, heartbeat frequency increased by 5 ± 13 beats per minute, while in group 2, it increased by 22 ± 10 beats per minute (P < 0.001). No postoperative complications were reported for either technique. Patients showed a preference of 67% for the alternative technique and 20% for the traditional, and 13% of patients were indifferent. Conclusion: The results identified intraosseous anesthesia as a valid alternative to conventional anesthesia in impacted lower third molar extraction.

• The Korea Journal of Herbology
• /
• v.28 no.4
• /
• pp.83-92
• /
• 2013

Objectives : Lespedeza Cuneata has been used to treat leukorrhea, asthma, stomach pain, diarrhea, acute mastitis, in Korean traditional medicine. According to recent studies, Lespedeza Cuneata has antioxidation, hypoglycemia, cell protective, insulin secretion, whitening, corpora cavernosa smooth muscle relaxation and antimicrobial activities, but it has been rarely conducted to evaluate the immuno-biological activity. The present study was examined to evaluate the anti-inflammatory effects of the Lespedeza Cuneata MeOH extract (LCE) in vivo and in vitro. Methods : In vitro, inflammatory mediators, such as cytokines, nitric oxide and prostaglandin $E_2$ were detected after the addition of LPS with or without LCE in Raw 264.7 macrophage cell line. In vivo, anti-edema effect of LCE was determined in the carrageenan-induced paw edema model in rats. Results : In vitro assay, LCE decreased release of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) via suppression of iNOS and COX-2 expression. LCE inhibited the phosphorylation of $I{\kappa}B$ indicating the suppression of NF-${\kappa}B$ pathway. In vivo assay, LCE significantly inhibited the formation of paw edema induced by carrageenan injection in rats. LCE effectively inhibited increases of hind paw skin thickness and inflammatory cell infilterations. Conclusion : These findings demonstrate that LCE has inhibitory effect on inflammatory mediators in LPS-activated Raw 264.7 cells and on paw edema in carrageenan-stimulated rats, showing the possibility of anti-inflammatory use of Lespedeza Cuneata.

• Journal of Korea Entertainment Industry Association
• /
• v.14 no.7
• /
• pp.193-202
• /
• 2020

This study was intended to present the magnitude of privacy infringement concerns and their relationship to consumer innovation (functional innovation, hedonistic innovation, social innovation, cognitive innovation), to identify differences among groups and to suggest implications for marketing strategies for the spread of new products. The implications of this study are as follows. First, functional innovation has shown that differences exist between groups. Analysts say that sensitive groups are buying products that can simplify their work immediately after release despite concerns over privacy violations. Second, hedonistic innovation has shown that differences exist between groups. These findings suggest that sensitive groups prefer novel products, products that give excitement and excitement about products, and products that give new enjoyment and fun that they have never known before. Third, social innovation has been shown that there is no difference between groups. These analyses show that the self-esteem of using products that others have never experienced before, and the curiosity that anyone envies, are purchased or used first. Finally, cognitive innovation showed that differences existed between groups. These analyses show that new products are purchased when they meet the functions, design, and innovation that consumers want.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.13
• /
• pp.107-118
• /
• 1973

Experiments were carried out to study the effectiveness of METAP as a slow released fertilizer on the growth, grain yield and its components of paddy rice, and to compare its effects with those of single fertilizers in the fields of 3 Crop Experiment Stations and 7 provincial Offices of Rural Development. The effectiveness of METAP seems to be different according to the physical and chemical characteristics of soil, the time of application, climatic conditions, variety and cultural methods. Therefore, the experimental results obtained from the above experiment are summurized as follows: 1. When METAP was applied into sandy soil, grain yield was increased due to increase of the number of panicles, and split application of METAP was more effective than basal only. However, in the reclaimed soil, not heavily percolated soil and fertile soil, no differences were observed between MET AP and single fertilizer applied plot. 2. When a rice variety, 'TONGIL' which is sensitive to the low temperature and produce higher yield in the early transplanting, was not transplanted early and air temperature is relatively lower during the ripening stage, the percentage of ripened grains and 1,000 grains weight were not higher in the METAP applied plots than in the single fertilizer applied plots.