• The Journal of the Acoustical Society of Korea
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• v.26 no.7
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• pp.361-365
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• 2007

Aero-pulsation noise, generally caused by geometric asymmetry of a rotating device, is one of considerable sources of annoyance in passenger cars using the turbocharged diesel engine. Main source of this noise is the compressor wheel in the turbocharger system, and can be reduced by after-treatment devices such as silencers, but which may increase the manufacturing cost. More effective solution is to improve the geometric symmetry over all, or to control the quality of components by sorting out inferior ones. The latter is more simple and reasonable than the former in view of manufacturing. Thus, an appropriate discrimination method should be needed to evaluate aero-pulsation noise level at the production line. In this paper, we introduce the accurate method which can measure the noise level of aero-pulsation and also present its evaluation criteria. Besides verifying the reliability of a measurement system - a rig test system-, we analyze the correlation between the results from rig tests and those from vehicle tests. The gage R&R method is carried out to check the repeatability of measurements over 25 samples. From the result, we propose the standard specification which can discriminate inferior products from superior ones on the basis of aero-pulsation noise level.

• Geophysics and Geophysical Exploration
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• v.8 no.4
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• pp.270-279
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• 2005

Under the research project supported by Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT), we have conducted the development of GPR systems for landmine detection. Until 2005, we have finished development of two prototype GPR systems, namely ALIS (Advanced Landmine Imaging System) and SAR-GPR (Synthetic Aperture Radar-Ground Penetrating Radar). ALIS is a novel landmine detection sensor system combined with a metal detector and GPR. This is a hand-held equipment, which has a sensor position tracking system, and can visualize the sensor output in real time. In order to achieve the sensor tracking system, ALIS needs only one CCD camera attached on the sensor handle. The CCD image is superimposed with the GPR and metal detector signal, and the detection and identification of buried targets is quite easy and reliable. Field evaluation test of ALIS was conducted in December 2004 in Afghanistan, and we demonstrated that it can detect buried antipersonnel landmines, and can also discriminate metal fragments from landmines. SAR-GPR (Synthetic Aperture Radar-Ground Penetrating Radar) is a machine mounted sensor system composed of B GPR and a metal detector. The GPR employs an array antenna for advanced signal processing for better subsurface imaging. SAR-GPR combined with synthetic aperture radar algorithm, can suppress clutter and can image buried objects in strongly inhomogeneous material. SAR-GPR is a stepped frequency radar system, whose RF component is a newly developed compact vector network analyzers. The size of the system is 30cm x 30cm x 30 cm, composed from six Vivaldi antennas and three vector network analyzers. The weight of the system is 17 kg, and it can be mounted on a robotic arm on a small unmanned vehicle. The field test of this system was carried out in March 2005 in Japan.

• The Journal of Korean Obstetrics and Gynecology
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• v.30 no.2
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• pp.49-70
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• 2017

Objectives: The present study is to observe the skin-regeneration, anti-wrinkle, whitening and skin moisturizing effects of Cheongsangbangpung-tang (CSBPT) with cytotoxicity. Methods: In the present study, cytotoxicity of CSBPT lyophilized aqueous extracts (yield=18.71%) was experimented against human normal fibroblast cells and B16F10 murine melanoma cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide (MTT) assay, and skin regeneration and anti-wrinkle effects were also showed through the assay of collagen type I synthesis by an enzyme immunoassay (EIA) kit as comparing with transforming growth factor (TGF)-${\beta}1$, hyaluronidase, collagenase and matrix metalloproteinase (MMP)-1 inhibitory assays as comparing with oleanolic acid (OA), and elastase inhibitory effects as comparing with phosphoramidon disodium salt (PP). In addition, whitening effects of CSBPT were observed by tyrosinase inhibitory assay and melanin formation test in B16/F10 melanoma cells as comparing with arbutin, and skin moisturizing effects were measured through mouse skin water contents test, respectively. Results: No CSBPT treatment related cytotoxic effects were demonstrated against human normal fibroblast cells and B16/F10 murine melanoma cells. CSBPT concentration-dependent increased collagen type I synthesis at human normal fibroblast cells. It also effectively suspreessed hyaluronidase, collagenase, elastase and MMP-1 activities, which were enzymes that related to declining of ECM and formation of wrinkle. CSBPT supressed B16/F10 melanoma cells's melanin productions with tyrosinase activity, which was an enzyme connected with melanin formation, and dose-dependent and significant increases of skin water contents were detected in CSBPT treated mouse skin as compared with vehicle control skins. Conclusions: CSBPT showed favorable and enough skin regeneration, anti-wrinkle, whitening and skin moisturizing effects at least in a condition of this experiment. However, more detail mechanism and in vivo skin protective efficacy studies should be conducted in future with the screening of the biological active compounds in individual herbs of Cheongsangbangpung-tang.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.391-397
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• 2009

Carnosine is a dipeptide ($\beta$-alanyl-L-histidine) found in mammalian brain, eye, olfactory bulb and skeletal muscle at high concentrations. Its biological functions include antioxidant and anti-glycation activities. The objectives of this study were to investigate anti-diabetic effects of carnosine as determined by blood glucose levels in glucose tolerance test (GTT) and insulin tolerance test (ITT), insulin level and serum biochemical and lipid levels in male C57BL/6J db/db mice. There were five experimental groups including normal (C57BL/6J), control (vehicle), and three groups of carnosine at doses of 6, 30, and 150 mg/kg b.w. Carnosine was orally administered to the diabetic mice everyday for 8 weeks. There was no significant difference in body weight changes in carnosine-treated groups compared to the control. The treatments of carnosine significantly decreased the blood glucose level in the diabetic mice compared with the control (p < 0.05) after 5 weeks. The treatments of carnosine also significantly decreased the blood glucose levels in GTT and ITT and glycosylated hemoglobin (HbA1c), compared with the control (p < 0.05). Carnosine at the dose of 6 mg/kg significantly decreased the serum insulin level compared to the control (p < 0.05). Carnosine significantly increased total proteins but significantly decreased lactate dehydrogenase and blood urea nitrogen compared with the control (p < 0.05). Carnosine also significantly decreased glucose, LDL, and triglyceride in the serum of diabetic mice compared to the control (p < 0.05). These results suggest that carnosine has a hypoglycermic effect resulting from reduction of glucose and lipid levels and that high carnosine-containing diets or drugs may give a benefit for controlling diabetes mellitus in humans.

• The Journal of Korean Obstetrics and Gynecology
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• v.29 no.1
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• pp.14-34
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• 2016

Objectives: The objective of this study was to evaluate the effects of cytotoxicity, skin regeneration, anti-wrinkle, whitening and skin moisturizing of Oncheongeum (OCE).Methods: The cytotoxicity of OCE lyophilized aqueous extracts (yield=13.82%) was observed against human normal fibroblast cells and B16/F10 murine melanoma cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium Bromide (MTT) assay, and skin regeneration and anti-wrinkle effects were also evaluated through the assay of collagen type I synthesis compared to the transformation of the growth factor (TGF)-β1, hyaluronidase, collagenase and matrix metalloproteinase (MMP)-1 inhibitory assays compared to oleanolic acid (OA), and elastase inhibitory effects compared to phosphoramidon disodium salt (PP). In addition, OCE’s whitening effects were measured by a tyrosinase inhibitory assay and melanin formation test in B16/F10 murine melanoma cells compared to arbutin, and skin moisturizing effects were observed through a mouse skin water content test, respectively. Results: No OCE treatment-related cytotoxic effects appeared on human normal fibroblasts and B16/F10 murine melanoma cells. OCE concentration-dependently increased the collagen Type I synthesis on human normal fibroblast cells, and also effectively inhibited hyaluronidase, elastase, collagenase and MMP-1 activities. In addition, OCE inhibited melanin production of B16/F10 murine melanoma cells and activity of tyrosinase. And significant and dose-dependent increases of skin water content were detected in OCE-treated mouse skin compared to vehicle control skins. Conclusions: OCE showed favorable and sufficient effects in skin regeneration, anti-wrinkle, whitening and skin moisturizing in this experiment. But more detail mechanisms and studies on the skin protective efficiency of in vivo are needed with the screening of active biological compounds in individual OCE herbs.

• Journal of Preventive Medicine and Public Health
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• v.32 no.3
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• pp.361-373
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• 1999

Objectives: Receive Operating Characteristic(ROC) curve with the area under the ROC curve(AUC) is one of the most popular indicator to evaluate the criterion validity of the measurement tool. This study was conducted to develop a standardized questionnaire to discriminate workers at high-risk of work-related musculoskeletal disorders using ROC analysis. Methods: The diagnostic results determined by rehabilitation medicine specialists in 370 persons(89 shipyard CAD workers, 113 telephone directory assistant operators, 79 women with occupation, and 89 housewives) were compared with participant's own replies to 'the questionnair on the worker's subjective physical symptoms'(Kwon, 1996). The AUC's from four models with different methods in item selection and weighting were compared with each other. These 4 models were applied to 225 persons, working in an assembly line of motor vehicle, for the purpose of AUC reliability test. Results: In a weighted model with 11 items, the AUC was 0.8155 in the primary study population, and 0.8026 in the secondary study population(p=0.3780). It was superior in the aspects of discriminability, reliability and convenience. A new questionnaire of musculoskeletal disorder could be constructed by this model. Conclusion: A more valid questionnaire with a small number of items and the quantitative weight scores useful for the relative comparisons are the main results of this study. While the absolute reference value applicable to the wide range of populations was not estimated, the basic intent of this study, developing a surveillance fool through quantitative validation of the measures, would serve for the systematic disease prevention activities.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2004.11a
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• pp.53-55
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• 2004

In emergency cases, such as the severe trauma involving the fracture of skull, spine, or cervical bone, from auto accident or a fall, and/or pneumothorax which can not be diagnosed exactly by the eye examination, it is necessary the radiological examination during transferring to the hospital for emergency care. The aim of this study was to design and evaluate the prototype of mobile medical image communication system based on CDMA 1X EVDO. The system consists of a laptop computer used as a transmit DICOM client, linked with cellular phone which support to the CDMA 1X EVDO communication service, and a receiving DICOM server installed in the hospital. The DR images were stored with DICOM format in the storage of transmit client. Those images were compressed into JPEG2000 format and transmitted from transmit client to the receiving server. All of those images were progressively transmitted to the receiving server and displayed on the server monitor. To evaluate the image quality, PSNR of compressed image was measured. Also, several field tests had been performed using commercial CDMA2000 1X-EVDO reverse link with the TCP/IP data segments. The test had been taken under several velocity of vehicle in seoul areas.

• Journal of Nutrition and Health
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• v.49 no.1
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• pp.18-27
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• 2016

Purpose: Our previous study demonstrated the hypoglycemic effects of mulberry (Morus alba L.) leaf and the underlying mechanisms. Here we explored the potency of mulberry twigs (TW) and root barks (RB) in postprandial hypoglycemic effects in vitro and in vivo. Methods: The major components of TW and RB were determined by high performance liquid chromatography (HPLC). Alpha-glucosidase inhibition and glucose/fructose uptake inhibition in Caco-2 cells were determined for TW, RB, and their major components, followed by an oral sugar tolerance test (OSTT) in streptozotocin-induced diabetic rats. Male Wistar rats were fed a high-fat diet for 2 weeks and then a single dose of streptozotocin (35 mg/kg B.W) was administered by intraperitoneal injection. Rats with fasting blood glucose levels above 126 mg/dL were randomly divided into 5 groups (n = 8/group) for the following treatments by gavage for 4 weeks: vehicle (normal control and diabetic control), 200 mg/kg B.W of TW or RB or 100 mg/kg B.W of oxyresveratrol (OXY). Results: OXY and mulberroside A were identified as the major components of TW and OXY, mongolicin, and kuwanon H for RB. A significant inhibitory activity on ${\alpha}-glucosidase$ was found for TW, RB, and OXY (p = 0.0099). There was a dose-dependent inhibition of TW and RB on the intestinal sugar uptakes in Caco-2 cells, showing a greater impact on fructose compared to glucose. The OSTT showed that TW and RB significantly delayed time to maximal concentration (p = 0.0088) and decreased maximal concentration (p = 0.0043) compared to the control group. Conclusion: These results suggest that TW and RB may have a postprandial hypoglycemic effect, particularly in the case of high fructose or sucrose intake. OXY was suggested as a contributor to the hypoglycemic effect of TW and RB. Further studies are needed for the systemic effect of TW and RB in circulation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.605-611
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• 2012

Sea cucumber, $Stichopus$ $japonicus$, is used not only as an outstanding tonic food but also as a traditional medicine for the treatment of asthma, hypertension, rheumatism, anemia, and sinus congestion. The purpose of this study was to examine sea cucumber as an anti-gastritis and anti-gastric ulcer in HCl-ethanol-induced gastric and $H.$ $pylori$-infected animal models. Thirty 7-week-old SD rats and Mongolian gerbils were divided into normal (Nor, n=6), control (Con, 60% HCl-ethanol+water, n=6), groupI (DSCI, 60% HCl-ethanol+sea cucumber 30 mg/kg, n=6), groupII (DSCII, 60% HCl-ethanol+sea cucumber 100 mg/kg, n=6), and group III (DSCIII, 60% HCl-ethanol+sea cucumber 300 mg/kg, n=6). Sea cucumber significantly suppressed gastric lesions and ulcers in the 60% HCl-ethanol-induced gastric model. Especially, 100 mg/kg of sea cucumber showed significantly inhibitory effects. In histopathological analysis of the $H.$ $pylori$ model, we found that sea cucumber augmented the eradication rates of $H.$ $pylori$ and attenuated gastric ulcer formation. Our results suggest that sea cucumber has inhibitory effects on gastritis and gastric ulcers. In addition, sea cucumber can be applied for the treatment of $H.$ $pylori$.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.517-528
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• 2007

Domestic or international existing researches regarding rail damage factors are focused on laying, vehicle conditions, driving speed and driving habits and overlook characteristics of track structure (elasticity, maintenance etc). Also in ballast track, as there is no special lateral spring stiffness of track also called as ballast lateral resistance in concrete track, generally, existing study shows concrete track has 2 time shorter life cycle for rail replacement than ballast track due to abrasion. As a result of domestic concrete track design and operation performance review, concrete track elasticity is lower than track elasticity of ballast track resulting higher damage on rail and tracks. Generally, concrete track has advantage in track elasticity adjustment than ballast track and in case of Europe, in concrete track design, it is recommended to have same or higher performance range of vertical elastic stiffness of ballast track but domestically or internationally review on lateral spring stiffness of track is very minimal. Therefore, through analysis of service line track on site measurement and analysis on performance of maintenance, in this research, dynamic characteristic behaviors of commonly used ballast and concrete track are studied to infer elasticity of service line track and experimentally prove effects of track lateral spring stiffness that influence curved rail damage as well as correlation between track elasticity by track system and rail damage to propose importance of appropriate elastic stiffness level for concrete and ballast track.