• Journal of the korean Society of Automotive Engineers
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• v.7 no.1
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• pp.48-54
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• 1985

One of the most probable reason of the apex seal damage in IR-2500 industrial Wankel (rotary) engine was believed to be the engine detonation. Both analytical and experimental studies were made with a view th find out engine detonation pressure. The stagnation detonation pressure $p_{03}$' was estimated based on the data from IR-2500 engine detonation tests, such as engine firing pressure, state of fresh charge at BDC and polytropic compression exponent. The estimated stagnation detonation pressure for the natural gas fueled IR-2500 engine was in excess of 3,700 psia. With natural gas liquid added to the natural gas the octane value of the fuel was lowered, thus, making the engine more prone to detonate. The estimated detonation pressure for the case with the mixed fuel was about 3,400 psia which was sufficiently high to break the apex seal. The subsequent engine lab tests performed on two identical engines with sole difference in the apex seal thickness between the two engines proved that the engine knock, in fact, was the villain of the apex seal failure.ilure.

• The Journal of the Korean dental association
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• v.15 no.1
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• pp.41-45
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• 1977

For biometric study on the widlth of mouth in singaporian the author measured the transversal width of mouth, Longitudinal width of mouth and Interdental space in 652 cases of the total cases 317 were male (chinese 235. malay50, Indian 32) and 335 Female (Chinese 260, malay 53. Indian 22) and Ages ranged from 5 to 25 yeass old. The fallowing result was obtained. 1) In Adult, transversal width of mouth was 54. 20±0.22mm in male, 53.00±0.10mm in female and 40.03±0.26mm in male, 39.39±0.30mm in female of children. 2) In Abult, Longitudinal width of mouth was 52.00±0.12mm in male, 48.40±0.15mm in female and 44.50±0.13mm in male 44.20±0.30mm in female of children. 3) In Adult, Interdental Space (anterior teeth) was 44.20±0.15mm in male. 44.00±0.20mm in Fmale and 38.40±0.15mm in male, 37.17±0.21mm in Female of Children.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.193-194
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• 2002

The frictional characteristics of natural rubber plates under various conditions including sliding speed, contacted ball size, and lubrication conditions were evaluated experimentally. The frictional force and the normal force were measured by a self-made tester pin and a load cell with strain gages. In the lubrication condition, the effect of sliding speed was not significant over tested speed range. But in the none-lubrication condition, according to increase the sliding speed, the friction coefficient was decreased. The coefficients of friction under various lubrication conditions were varied from 0.03 to 0.32 and under none-lubrication condition was varied from 2.54 to 4.74.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.10a
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• pp.101-101
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• 2003

다양한 식품 소재의 창출을 목적으로 그 기초자료로서 감국에 대한 화학적조성을 조사하였다. 일반성분은 감국의 수분함량이 10.51%, 조단백 9.38%, 지방 3.47%, 회분 4.87%, 환원당 13.12%, 조섬유가 9.03%, 비타민 C의 함량은 0.74%였다. 총 페놀 화합물의 함량 0.43mg%이였으며, 총 카로티노이드 함량은 0.84mg%로 나타났다. 아미노산 조성은 전체 아미노산 중 필수아미노산이 차지하는 비율은 41.42% 이고, 비필수아미노산의 비율은 58.58%였다. 감국의 아미노산 함량은 glutamic acid가 13.54%로 가장 많았고, 그 다음이 alanine(11.25%), aspartic acid(10.35%) 순으로 나타났다. (중략)

• Korean journal of applied entomology
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• v.54 no.2
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• pp.115-119
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• 2015

Four species of aphelinids from Unaspis euonymi (Comstock) infesting Japanese spindle (Euonymus japonicus Thunb. (Celastraceae)) leaves and twigs were collected and identified as Ablerus perspeciosus Girault, Encarsia citrina (Craw), Marietta carnesi (Howard) and Pteroptrix machiaveli (Girault). Of these, Pteroptrix machiaveli (Girault) is newly documented in the Korean fauna of Aphelinidae. Brief diagnostic criteria and illustrative photographs of these species are provided and there is information on the distribution and hosts of each species as well.

• Korean journal of applied entomology
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• v.54 no.2
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• pp.63-71
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• 2015

A taxonomic review of Korean Laccophilus Leach is presented. Five species are recognized, three of which [L. hyalinus (De Geer), L. lewisius Sharp and L. minutus ($Linn{\acute{e}}$)] previously recorded in Korea are incorrect identification of L. vagelineatus Zimmermann, L. lewisioides Brancucci and L. difficilis Sharp, respectively. Habitus and SEM photographs, key and diagnoses of the species are provided.

• 한국전기화학회:학술대회논문집
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• 2005.07a
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• pp.335-340
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• 2005

Amorphous $MgNi_{1-x}Ti_x$ alloys with the composition of x=0.02, 0.03, 0.05 and 0.07 were synthesized by mechanical alloying. The synthesized alloys were investigated by electrochemical test, XRD and SEM. As increasing Ti concentration, the initial discharge capacity was raised more than that of nanocrystalline Mg-Ni 289 mAh/g, but the electrodes were degraded faster. Comparing to other synthesized alloys, $MgNi_{0.95}Ti_{0.05}$ alloy showed the highest initial discharged capacity 474 mAh/g and maintained $54\%$ of the initial capacity after 10 cycles.

• Applied Microscopy
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• v.17 no.2
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• pp.41-54
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• 1987

This experiment was performed to investigate the acute and chronic effects of lead on cerebral cortex. In acute treatment, mouse were injected with lead acetate at dose of 0.3 mmole/kg body weight, and in chronic treatment, mouse were supplied 0.03 M lead acetate sol. in the place of water. After treatment, mouse were sacrificed at time intervals of 24, 48, 72, and 96 hours in acute treatment and at time intervals of 4 weeks and 8 weeks in chronic treatment. In acute treatment, acetylcholinesterase activity is reduced at 72 hours and recovered at 96 hours in homogenate, and reduced at 24 hours and recovered at 72 hours in crude synaptosomes. In chronic treatment, acetylcholinesterase activity is increased in young mouse but reduced in mother mouse. Ultrastructural changes were composed of swelling of Golgi apparatus, nerve terminals with diminished synaptic vesicles, and vacuolated myeline lamellae of myelinated axon.

• Journal of the korean academy of Pediatric Dentistry
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• v.10 no.1
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• pp.123-129
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• 1983

This study was designed to find out the prevalence d the fused teeth in the primary dentition and their successors. The clinical and panoramic radiographic examination was undertaken of 5226 children (male 2812, female 2414) attended department of Pedodontics, College of Dentistry, Yon Sei University, Seoul, Korea. The results were as follows; 1. The prevalence of the fused teeth in the primary dentition was 1.03 percent and female (1.2%) affected more frequently than male (0.89%). 2. Compare with the maxilla and mandible, the prevalence of the fused teeth were higher in the mandible than in the maxilla. 3. The fusion of the primary teeth were occured between central with lateral incisor in the maxilla, and central with lateral and lateral with canine in the mandible. 4. There were 33 cases (61%) of succeding teeth missing among 54 case of the rused teeth.

• Journal of the Korean Society of School Health
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• v.23 no.2
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• pp.266-275
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• 2010

Purpose: The aims of this study is to examine the relationships among spiritual well-being, aggression and happiness of the students in two Christian Universities. Methods: The data were collected from 486 students who were attending Christian Universities in Jeonbuk province. General characteristics, mean value, and correlations were performed using SPSS 18.0 Program to analyze the data. Results: The mean value of the spiritual well-being was 72.03 (SD=9.80), the mean value of aggression was 67.56 (SD=13.90), and the mean value of happiness was 19.54 (SD=4.23). Relationships between spiritual well-being and aggression showed negative correlation ((r=-.251, p<.01), between spiritual well-being and happiness showed positive correlation (r=.455, p<.01), and between happiness and aggression showed negative correlation (r=-.305, p<.01). Conclusion: The findings of this study provide basic data for the development of education programs for personality training and curriculum.