• Journal of Applied Reliability
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• v.11 no.3
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• pp.235-244
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• 2011

Hydraulic hose assemblies deliver a fluid power in various oil pressure equipment such as construction machinery, automobile, aircraft, industrial machinery, machine tools and machinery for ships. Also, they are widely used as pipes in oil pressure circuit. When we estimate their lifetime, it is essential to conduct an accelerated life test by choosing the factor that suits the usage condition of the test object since traditional test method for estimating lifetime under the influence of various external factors incurs hardship in terms of time and expenses. The objective of this study is to propose an acceleration model that takes both temperature and pressure without flexing condition into consideration. The lifetime is estimated by applying the proposed temperature-nonthermal acceleration model to the test data. And we compare the proposed temperature-nonthermal acceleration model and the accelerated life equation suggested by John(1994).

• Proceedings of the Korean Reliability Society Conference
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• 2006.05a
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• pp.116-125
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• 2006

Piston assemblies, which are key components of hydraulic high pressure pumps & motors, are major failure products operating at high pressure and high speed, and the main failure mode is wearout of the shoe surface. To predict the actual life of piston assemblies. we require to find out the most sensitive parameters and establish related empirical formula. In this study, we analyzed the life of piston and shoe assemblies in accordance with variation of speed, pressure, and temperature to reduce the life test time, then analyzed the result of combined accelerated life test which is applied by high speed, speed pressure, and high temperature simultaneously, and finally developed combined accelerated life test model.

• Clinics in Shoulder and Elbow
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• v.1 no.1
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• pp.78-82
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• 1998

The following will describe a method of evaluating the SLAP lesion in the recurrent anterior dislocation of the shoulder. We have named it the biceps load test. The biceps load test is performed with the patient in the supine position and the arm to be examined is abducted 90/sup°/, and the forearm is in the supinated position. First, the anterior apprehension test is performed. When the patient become apprehensive, the patient is allowed active flexion of the elbow, while the examiner resists elbow flexion. If the apprehension is relieved or diminished, the test is negative. If aggravated or unchanged, the test is positive. A prospective study was performed, in which 75 patients who were diagnosed as having recurrent unilateral anterior instability of the shoulder underwent the biceps load test and arthroscopic examination. The biceps load test showed negative results in 64 of these patients, of which the superior labral-biceps complex was intact'in 63 cases and only I shoulder revealed a type n SLAP lesion. E]even patients with a positive test were confirmed to have type n SLAP lesions. A positive biceps load test represents an unstable SLAP lesion in a patient with recurrent anterior dislocation of the shoulder. The biceps load test is a reliable test for evaluating the SLAP lesion in the recurrent anterior dislocation of the shoulder(sensitivity: ,9] .7%, specificity: 100%, positive predictive value: 1.00 and negative predictive value: 0.98). Biceps contraction increases the torsional rigidity ?of the glenohumeral joint and long head of biceps tendan act as internal rotator of the shoulder in the abducted and externally rotated position. These stabilize the shoulder in abduction and external rotation position in the biceps load test.

• Toxicological Research
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• v.24 no.1
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• pp.11-15
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• 2008

In this research the genotoxic effect of $Polycan^{TM}$ ${\beta}$-glucans originated from Aureobasidium pullulans SM-2001, was evaluated using the mouse micronucleus test. $Polycan^{TM}$ was administered once a day for 2 days by oral gavage to male ICR mice at doses of 1000, 500 and 250 mg/kg. Cyclophosphamide was used as a known genotoxic agent in a positive control group. The appearance of a micronucleus is used as an index for genotoxic potential. The results obtained indicated that $Polycan^{TM}$ shows no genotoxicity effect up to 1000 mg/kg dosing levels. In addition, it is also considered that there were no problems from cytotoxicity of $Polycan^{TM}$ tested in this study because the polychromatic erythrocyte ratio was detected as > 0.47 in all tested groups.

• Herbal Formula Science
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• v.17 no.2
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• pp.203-213
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• 2009

Objectives : The aim of this study was to investigate an effect of Bojungiki-Tang in two cases of the Gastric dysmotility-like Dyspepsia in functional dyspepsia Methods : Subjects were 2 patients with Gastric dysmotility-like Dyspepsia. The patients had suffered from a dyspepsia that were not improved by medical treatments. We gave Bojungiki -Tang to the patients 30 minutes after each meal and tried acupuncture and moxibustion 2 times every day. And we had evaluated the condition of patients using a Ryodoraku test and ordinal scales. Results : After the comparison between an admission and discharge date at Ryodoraku test and ordinal scales, we knowed that conditions of two Gastric dysmotility-like Dyspepsia patients had improved. Conclusions : Bojungiki-Tang is effective on the improvement of conditions in the Gastric dysmotility-like Dyspepsia patients.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.2
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• pp.212-216
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• 2011

In traditional medicines, Dansam-samul-tang and Samwhang-sasim-tang extracts were known to effects of antioxidant and antimicrobial activity. To investigate the safety evaluation of skin, these extracts were measured to skin safety testing such as primary skin irritation test, eye irritation test and skin sensitization test. The results of the primary skin irritation test and eye irritation test in vitro showed that these extracts included in the nonirritating area. Skin sensitization test results by Guinea Pig Maximization (GPMA) indicated that there was no allergy reaction. Therefore, Dansam-samul-tang and Samwhang-sasim-tang extracts were very safe in every safety test of skin. These results suggests that Dansam-samul-tang and Samwhang- sasim-tang extracts in 1 % concentration can be useful cosmetic ingredients.

• International Journal of Air-Conditioning and Refrigeration
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• v.15 no.4
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• pp.147-155
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• 2007

Mobile air conditioning systems work under widely changing operating conditions. To understand the system behavior under such dynamic conditions, a test facility that can impose transient loads as well as conducting dynamic measurements is needed. To test mobile air conditioning systems including their dynamic performance under various drive cycle patterns without using full scale vehicles in a wind tunnel, a new test facility, called "dynamic simulator," is described. It can replicate real vehicle operating conditions by interacting with the system being tested based on the measured system performance and subsequently adjusting the air properties returning to the test system based on the results of a numerical cabin model. A new dynamic simulator has been designed, constructed, and verified for performing dynamic tests. It was successful in controlling the temperature and relative humidity of the air returning to the test unit within ${\pm}0.7^{\circ}C$ and ${\pm}4%$ of their respective intended values. The verification test under the New European Driving Cycle demonstrated that detailed transient behavior of the mobile air conditioning system could be measured by using this dynamic simulator.

• Journal of Genetic Medicine
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• v.17 no.2
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• pp.68-72
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• 2020

Purpose: Trisomy 21, the cause of Down syndrome (DS) with various medical problems, is the most common aneuploidy during the fetal period. For diagnosis, a non-invasive screening test using maternal blood, which cannot be confirmed and invasive confirmation test with a risk of miscarriage, may be performed. The trophoblast retrieval and isolation of the cervix (TRIC) have been proposed by some researchers as an alternative to overcome the limitations of current tests. We experimented using TRIC to identify the possibility of trisomy 21 for the first time in Asia. Materials and Methods: Three cases of DS were analyzed confirmed by invasive tests (chorionic villus sampling, amniocentesis). All samples of trophoblasts immediately were immersed in phosphate-buffered saline and processed with formalin for fixation. The trophoblasts were isolated using an anti-human leukocyte antigen-G antibody coupled to magnetic nanoparticles. β-human chorionic gonadotropin (hCG)-expressing cells were considered as trophoblast cells, and the detection rate calculated. DS was confirmed by fluorescence in situ hybridization (FISH). Results: The mean trophoblast detection rate using β-hCG was 78.1%, and the detection rate using FISH was 22.2%. In all cases, the trisomy of chromosome 21 was identified. Conclusion: Trophoblast can be obtained from the five weeks of gestation and has a high detection rate, so it is noted that it can replace the current prenatal genetic test. To realize the clinical application as a prenatal genetic test, we will need additional efforts to identify trisomy 21 as well as other chromosomal abnormalities in future large-scale studies.

• Toxicological Research
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• v.32 no.2
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• pp.159-173
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• 2016

Crickets have been attracting considerable interest in the field of nutrition and toxicology due to the global exhaustion of food resulting from a growing population. The cricket is normally eaten in several countries after roasting, similar to the grasshopper; however, safety evaluation data on cricket powder is limited. Here, we performed general toxicity studies of cricket powder including a single, 2-week repeated dose range evaluation test, a 13-week repeated oral dose toxicity test in Sprague-Dawley rats, a single oral dose toxicity test in Beagle dogs, and a skin sensitization test in guinea pigs following the Organization for Economic Cooperation and Development test guidelines 406 and 408 in addition to Good Laboratory Practice. To investigate the NOAEL and target organs of cricket powder, Sprague-Dawley rats were allocated to 4 groups: vehicle control, 1,250 mg/kg, 2,500 mg/kg, 5,000 mg/kg dose test groups and cricket powder was administered over 13 weeks after single dose and dose range finding studies in rats based on the results of the single oral administration toxicity study in rats and Beagle dogs. The results of the study showed that the NOAEL of cricket powder was over 5,000 mg/kg for both sexes of rats without adverse effects in a 13-week repeated oral toxicity study and there was no skin hypersensitivity reaction. Therefore, our results reveal that crickets can be widely used as a new substitute food or nutrient resource.

• Toxicological Research
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• v.23 no.3
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• pp.245-251
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• 2007

Water extract of Cordyceps militaris grown upon Protuetja dreujtarsis (CMPD) was examined for the genetic toxicity-bacterial mutagenicity, chromosome aberration, and micronucleus formation. For mutagenicity assay, bacterial reversion test with Salmonella typhimurium TA98, TA100, TA1535, TA 1537, and E. coli WP2uvrA were performed. The extract at the concentrations of $50{\sim}5,000{\mu}g/plate$ did not induce mutagenicity at all. Chromosome aberration test was performed by using Chinese lung (CHL) cells. There was no significant chromosome aberration in CHL cells with S-9 mixture at the concentrations of $312.5{\sim}1,250{\mu}g/ml$ of the extract and without S-9 mixture at the concentrations of $1.2{\sim}19.5{\mu}g/ml$ of the extract. For micronucleus test, ICR mice were treated with the extract at the dose of 0.5, 1, and 2g/Kg. The frequencies of the micronucleated polychromatic erythrocytes (MNPCE) in bone marrow preparations of the extract-treated group were not increased compared to the untreated control group. Taken together, our results show that water extract of CMPD did not induce any harmful genotoxicity.