• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.5
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• pp.563-574
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• 2020

Currently, road tunnels and railroad tunnels are building smoke control systems to emit toxic gases and smoke from fires. Among the various smoke control systems, the transverse smoke control system has the disadvantage that air supply or exhaust is performed on only half of the cross-section, rather than air supply or exhaust on the entire cross-section of the tunnel as air is supplied or exhausted by partitioning the wind path. Therefore, this study analyzed the effect of exhaustion through numerical analysis and scaled model tests on the zoning smoke control system, which improved the limitations of the transverse smoke control system. As a result of the scaled model test, the transverse ventilation system exhibited a 25.6% smoke control rate based on the state where no smoke was controled, and zoning smoke control system showed a smoke control rate of 40.8%. In addition, as a result of numerical analysis, it was found that transverse ventilation system did not control fire smoke spreading from the tunnel and continued to spread. On the other hand, zoning smoke control system was found to be smoke controled within a certain section due to the air curtain effect and the flue gas effect.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.2
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• pp.88-93
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• 2013

Purpose: Maxillary sinus elevation has been widely used to enable insertion of endosseous implants in severely resorbed maxilla. Maxillary sinusitis after this procedure was considered to be the major drawback, therefore, preoperative evaluation of paranasal sinus is considered to be important. In order to evaluate the condition of the sinus, we used Waters' projection. In this study, asymptomatic patients were evaluated by Waters' view, and compared to timing to assess the sinus cavity. Methods: The retrospective study was based on 14 patients who were performed sinus elevation surgery in Seoul National University Dental Hospital. These patients did not show any signs of maxillary sinusitis. These patients were taken Waters' view at preoperative, postoperative 1 day, 3 months, 6 months. In Waters' view, presence of air fluid level, radiopacity of sinus wall, or radiopacity of entire maxillary sinus were evaluated. The density, and sinus dimension changes were assessed using Adobe Photoshop CS5$^{(R)}$ (Adobe Systems Inc., San Jose, CA, USA). Results: Findings of Waters views in patients with clear maxillary sinus at preoperative time were followed by elevated sinus floor with transplanted bone, mucosal swelling, and air fluid level. At postoperative 3 months, and 6 months, the radiographic findings were similar to preoperative state. By contrast, patients with preoperative mucosal swelling, or haziness in sinus cavity showed radiopacity entire sinus in Waters' view. In cases of the patients who were treated with simultaneous treatment to mucosal swelling, good status of sinus cavity were found. Conclusion: Although Waters' projections provide the limited information, and is less sensitive method compared with computed tomography, it is simple, easy, and economical method to assess of maxillary sinus. We suggest using Waters' view as radiographic routine tool for evaluation of sinus condition, especially in the sinus elevation surgery.

• Polymer(Korea)
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• v.27 no.5
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• pp.397-404
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• 2003

The interaction of cell adhesive protein and polypeptide with bone marrow stromal stem cells (BMSCs) grown in tissue engineered films and scaffolds were examined. Several proteins or polypeptide known as cell-adhesive were coated adsorption on poly(lactide-co-glycolide) (PLGA) films and scaffolds and adhesion and proliferation behavior of BMSC on those surfaces were compared. The protein and polypeptide used include collagen IV, fibrinogen, laminin, gelatin, fibronectin, and poly(L-lysine). The protein and polypeptide were adsorbed on the PLGA film surfaces with almost monolayer coverage except poly(L-lysine). BMSCs were cultured for 1, 2, and 4 days on the protein- or polypeptide-adsorbed PLGA films and scaffolds. The cell adhesion and proliferation behaviors were assessed by sulforho damine B assay. It was observed that the protein- or polypeptide-adsorbed surfaces showed better cell adhesion and proliferation than the control.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.321-327
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• 2020

Engine oil leaks comprise the largest percentage of the major quality problems that have occurred during the engine production process for military land system equipment over the last two years. To minimize this, it is essential to understand the root cause of the engine oil leakage and perceive the more common leakage area, as well as reduce the quality costs of pre-identification for leaks in the engine assembly process and single items. Therefore, in this study, the mass production quality of engines installed and operated in power equipment was improved by visualizing the engine oil leakage injected with the fluorescent dye and increasing the identification of the engine oil leak phenomenon. For this reason, the possibility of substituting the engine oil was considered and the engine oil was injected with the fluorescent dye. The maintenance was improved by reforming the engine oil injection process and leakage inspection process. Finally, these results suggest that the quality costs between mass production processes can be minimized by ensuring the reliability of military engines by reducing the user's complaints and improving the quality control capabilities of engine manufacturers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.397-404
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• 2020

The military tactical vehicle currently being operated is manufactured by improving the parts of commercial vehicles. In addition, the power supply system is applied by installing a separate converter inside the communication room to secure the operating environment of communication equipment. On the other hand, due to electromagnetic radiation noise, there are problems in frequent noise and deterioration in communication sensitivity during wireless communication in vehicles. To improve these, an advanced power supply system is applied, which is also equipped with an alternator to receive power required for communication equipment reducing broadband electromagnetic radiation noise. An additionally installed alternator, which is located in the engine room, is separated from the communication room where communication equipment is operated and is expected to reduce the effect of electromagnetic radiation noise generated from the power supply system. To verify these, a broadband radiation test was performed on a previous and advanced one. As a result, the broadband radiation noise of vehicles with an applied advanced power supply system satisfied all of the domestic vehicle safety standards and reduced in most of the sections except for some frequencies compared to previous typed vehicles. In particular, broadband radiation noise was decreased by up to 10.751 dB𝜇V/m in the vertical sections in 170 to 200 MHz on the right side of the vehicle.

• Herbal Formula Science
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• v.13 no.2
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• pp.101-110
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• 2005

The present study was conducted to compare antioxidant activity of Cuscutae Semen, Psoraleae Fructus, Cnidii Fructus and Epimedii Herba by DPPH radical scavenging activity. The extract was studied using diphenyl-picryl-hydrazyl (DPPH) for DPPH method. DPPH radical scavenging activity was measured after. .10, 20 and 30 minutes. The extract was tested by 1, 5, 10, 50, 100, 500 and $1000{\mu}g/ml$ concentrations. The results showed that the extract scavenged DPPH radical with time-dependent manner. Also, the extract showed dose-dependent DPPH radical scavenging activity. The extract of Cuscutae Semen, Psoraleae Fructus, Cnidii Fructus and Epimedii Herba scavenged DPPH radical with the IC50 being 2.7, 3.2, 2.9 and 1.1 mg/ml, respectively. In conclusion, the extract of Epimedii Herba, Cuscutae Semen, Cnidii Fructus and Psoraleae Fructus have antioxidant activity for the treatment of male sterility.

• Korean Journal of Environmental Agriculture
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• v.20 no.2
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• pp.108-111
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• 2001

This study examined effects of aqueous extracts of rice bran on the inhibition of germination and early growth of annual weeds, barnyardgrass and eclipta. Germination of barnyardgrass treated with 5%(w/v)-sterilized and nonsterilized extracts of rice bran were inhibited by 27% and 63% at 7 days after treatment(DAT), respectively, compared to control. However, plant height and fresh shoot weight of barnyardgrass treated with aqueous extract of rice bran was reduced significantly at higher than 1% for both sterilized and nonsterilized extracts. Plant height and fresh shoot weight of barnyardgrass treated with 5% extract of rice bran were inhibited by 66 to 68% and 75 to 78% at 7 DAT, irrespective of sterilization. The germination of eclipta treated with sterilized and nonsterilized extracts of rice bran were significantly inhibited at concentrations of more than 0.5% and completely at 4% and 5%. Plant height and fresh shoot weight of eclipta affected by the rice bran extracts showed trends similar to the germination rate. The sterilization of rice bran extract resulted in higher inhibition of germination and early growth of eclipta. Rice bran extract was more inhibitory to the germination and growth of eclipta than barnyardgrass. These results suggest that aqueous extracts of rice bran may have inhibitory potential to germination and early growth of weeds.

• Korean Journal of Environmental Agriculture
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• v.20 no.2
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• pp.93-98
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• 2001

A chilling-tolerant japonica-type and a chilling-susceptible indica-type of rice (Oryza sativa L.) plants were compared with respect to various physiological parameters during chilling and subsequent recovery. The japonica-type and the indica-type of rice cultivars used were Ilpumbyeo and Taebaekbyeo, respectively. The two rice cultivars exhibited little or no differences in the changes of leaf fresh weight and chlorophyll content during chilling at $5^{\circ}C$ for 3 days. During subsequent recovery at $25^{\circ}C$, however, Ilpumbyeo restored its growth more rapidly than Taebaekbyeo. Since the changes of relative water content, malondialdehyde production, an estimate of lipid peroxidation, and chlorophyll fluorescence were significantly different in the two rice cultivars during the chilling and subsequent recovery, they were found to be more sensitive physiological parameters than fresh weight and chlorophyll content. However, the differences in relation to water content, malondialdehyde production, and chlorophyll fluorescence between the two rice cultivars were smaller during chilling than those during subsequent recovery. These results suggest that relative water content, malondialdehyde production, and chlorophyll fluorescence could widely be used as important physiological parameters for screening chilling-tolerant plants.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.3
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• pp.361-366
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• 2010

This study was practiced to investigate the existing study trends for Injinho that is numerously used for hepatobiliary diseases in oriental medicine. The studies selected from the domestic academic database included the following keywords in the title or abstract; 'Artemisia capillaris', 'Artemisia iwayomogi', 'Artemisia scoparia'. The studies considered were those published from January 1990 to May 2009. 198 studies were found to include the keywords related to the study subjects either in their title of contents or abstracts, and 104 studies among them were finally selected as subjects for this study. 81 studies among 104 studies(78%) were published between 2000 and 2009, while 23 studies(22%) were published between 1990 and 1999. Classification was proceeded according to study subjects as followed; 23 studies confirming hepatoprotective effect after artificial liver damage in a number of cells or the organ itself, 18 studies on anti-tumor effect, 12 studies on hyperlipidemia and fatty liver disease, and 4 studies on liver cirrhosis and hepatocyte regeneration. Furthermore, classification was conducted according to study methods as followed; 56 studies practicing in vitro, 33 studies practicing in vivo, 11 studies practicing both in vitro and in vivo. 2 studies on specific cases and 1 study on documentary records. The majority of studies report the affirmative effects of Injinho. However most study methods were restricted to in vitro and in vivo. Hereafter, case reports on various fields and multicenter clinical trials on Injinho is necessary.

• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.273-278
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• 2008

There have been studies about dog’s personality and behavior, which is helpful to breed dogs as guide or companion. In this study, a questionnaire was developed using 54 Jindo dogs, which considered ten items about aggressiveness and sociability. The scores were analyzed by principle component analysis (PCA), after accounting for four variables: age, gender, growing place, and coat-colors. Our results from the PCA indicated three principle components, which classified ‘aggressiveness’, ‘sociability’ and unknown factor. The four variables did not significantly affect aggressiveness(P>0.05). However, there was a relationship between coat-color and sociability, i.e., the Jindo dogs with fawn color were more sociable than the white ones(P<0.1).