• International Journal of Aeronautical and Space Sciences
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• 제16권4호
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• pp.529-536
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• 2015

Various R&D programs for rocket-based combined cycle (RBCC) engines have progressed worldwide for the space development and the defense applications. As a way toward indigenous domestic RBCC program, a preliminary design of flight test conditions was studied in this study for a sub-scale RBCC engine using a sounding rocket. Launch and flight profiles were calculated for several booster options and compared with that of HyShot II program. The result shows that the Korea Sounding Rocket-II (KSR-II) is a proper candidate to perform the flight test available in Korea. The recommend flight test conditions with KSR-II are Mach 6.0 with a test vehicle of 230 kg and Mach 7.4 with 50 kg. Present study will soon be followed by a design of sub-scale RBCC for a flight test using a sounding rocket.

• 항공우주시스템공학회지
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• 제7권4호
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• pp.49-54
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• 2013

A turbopump for a 75 ton class liquid rocket engine was tested at full speed for 20 seconds using model fluid. Liquid nitrogen is used for the oxidizer pump, water for the fuel pump, and hot gas for the turbine. The non-cavitating head of pump from the turbopump assembly test showed a good agreement with that from the pump component test. The relative difference of turbine efficiency between the turbopump assembly test and the turbine component test was 0.3% only. Suction performance from the turbopump assembly test was higher than that of pump component test, which resulted from the thermodynamic effect of cavitation.

• The Korean Journal of Physiology and Pharmacology
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• 제17권4호
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• pp.321-329
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• 2013

Rodents exposed to a 15-min pretest swim in the forced swimming test (FST) exhibit prolonged immobility in a subsequent 5-min test swim, and antidepressant treatment before the test swim reduces immobility. At present, neuronal circuits recruited by antidepressant before the test swim remain unclear, and also less is known about whether antidepressants with different mechanisms of action could influence neural circuits differentially. To reveal the neural circuits associated with antidepressant effect in the FST, we injected desipramine or citalopram 0.5 h, 19 h, and 23 h after the pretest swim and observed changes in c-Fos expression in rats before the test swim, namely 24 h after the pretest swim. Desipramine treatment alone in the absence of pretest swim was without effect, whereas citalopram treatment alone significantly increased the number of c-Fos-like immunoreactive cells in the central nucleus of the amygdala and bed nucleus of the stria terminalis, where this pattern of increase appears to be maintained after the pretest swim. Both desipramine and citalopram treatment after the pretest swim significantly increased the number of c-Fos-like immunoreactive cells in the ventral lateral septum and ventrolateral periaqueductal gray before the test swim. These results suggest that citalopram may affect c-Fos expression in the central nucleus of the amygdala and bed nucleus of the stria terminalis distinctively and raise the possibility that upregulation of c-Fos in the ventral lateral septum and ventrolateral periaqueductal gray before the test swim may be one of the probable common mechanisms underlying antidepressant effect in the FST.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제35회 추계학술대회논문집
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• pp.343-346
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• 2010

한국형발사체 추진기관 개발을 위한 연소기 연소시험설비, 터보펌프 실매질 시험설비, 엔진 지상 및 고공모사 연소시험설비, 추진기관시스템 시험설비 구축 계획에 대해 간략히 기술하였다. 연소기, 터보펌프, 엔진 시험설비에서는 75톤급 액체로켓엔진의 부품 및 엔진시스템의 개발 및 인증시험을 수행할 예정이고, 추진기관시스템시험설비에서는 한국형발사체 1/2/3단용 추진기관시스템의 개발 시험을 수행할 예정이다. 추진기관 시험설비는 나로우주센터에 건설될 예정이며 구축 일정, 예산, 안전거리, 효율성 등을 고려하여 구축하고자 한다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1384-1387
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• 2003

Pressurization test is usually required in aircraft full-scale static test. There are several test conditions including pressurization of cockpit, fuselage fuel tank, air inlet duct for T-50 full-scale static test. In this paper, the test conditions, equipment, piping analysis for the pressurization test are introduced. Tank simulation test is performed to verify the validity of piping analysis and to find good tuning parameters for the pressurization channel in the servo controller. Several test setup for pressurization of T-50 test is introduced. Test article volume is filled by form, $60%{\sim}80%$ volume is reduced for the T-50 full-scale static test. Pressurization system is connected to servo controller which also controls hydraulic actuator. Load and pressure control is synchronized by using the same servo controller during T-50 test. Typical control result for pressurization test condition is shown. Pressurization tests of T-50 full-scale static test was completed successfully.

• 동의신경정신과학회지
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• 제12권2호
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• pp.185-191
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• 2001

Objectives: This study aimed to evaluate the usefulness as a screening test of Clock Drawing Test(CDT) compared with the standard K-DRS in probably dementia. Methods: The subjects for this study consisted of 19 elderly persons who visited to the outpatient department of Oriental Neuropsychiatry of the Kyunghee Oriental hospital. They received the K-DRS and the Clock Drawing Test. Three observers evaluated them with circle, numbers, hands. Inter-rater reliability of scores from Clock Drawing Test was assessed and Pearson correlation coefficients were used to examined the relationships between scores from Clock Drawing Test and K-DRS. Results: Correlations between individual raters was highly significant (r= .957, .974, and .970, respectively: p<.001). There was stastically significant correlations between K-DRS and CDT scores (r= 0.849, p<.001). Conclusions: The CDT can be rated reliably by observers and correlations between CDT and K-DRS is significantly high. We confirmed the usefulness of CDT as simple, easily administered, low cost, and reliable general screening test for dementia.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.539-545
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• 2010

The field plate test has a good potential for determining since it measures both plate pressure and settlement. The deformation modulus of rock mass is differently measured for status of structures. The values of deformation modulus are obtained from laboratory test (uniaxial and triaxial test) and field test (pressuremeter test). Plate load test should be conducted by different loading plate sizes for geological structure of rock mass and scale of structures. In this paper, large plate load tests were performed to predict of structure's behavior and evaluate the ultimate bearing capacity of the foundation on soft rock. Simultaneously, deformation modulus of rock mass was estimated by back analysis of stresses measured in field test under rock mass. Finally, we verified the validation of deformation modulus of rock mass through result of large plate load test and numerical simulation.

• 대한전기학회논문지:전력기술부문A
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• 제55권8호
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• pp.322-328
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• 2006

In this paper, The impulse un-tripping characteristics and the electro magnetic compatibility characteristics are compared with each other. The performance of impulse un-tripping test exists at domestic standard (KSC 4613). However test items are insufficient because the more test items such as EMC exist at international standard (IEC). Also, Electric Appliances Safety Certificate has taken the certificate test since July 2004 in Korea but did not confirm the EMC performance for RCCBs made in Korea. Thus, in this paper, We experiment with Oscillatory waves immunity test and the 7 EMC tests for 32 RCCBs of 4 types (mini, home standard, plug, outlet) for 16 brands according to IEC standard 61009-1 and 61008-1. As a result, 24 RCCBs proved to be poor for surge immunity test. However the RCCBs operating incorrectly for surge immunity test operate correctly for oscillatory waves immunity test. Thus, the correlation between oscillatory waves immunity test and EMC test is little and standard for compatibility of combination surge at IEC 61000-4-5 should be added to KS standard as soon as possible.

• Nuclear Engineering and Technology
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• 제32권1호
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• pp.10-16
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• 2000

Preliminary experiment was peformed to investigate the leaching characteristics of paraffin waste forms that had been recently generated in large quantities at domestic nuclear power plants. At first, waste simulants whose compositions were different in mixing ratio of paraffin to boric acid were prepared. Their compressive strengths were measured and ninety-day leaching test of specimen including cobalt was carried out according to ANSI/ANS-16.1 test procedure. Water immersion test was also conducted keeping pace with leaching test and the weight change and the compressive strength of specimen were observed after ninety days. The compressive strength of waste form exhibited 666 psi (4.53 MPa) in the case where mixing ratio of boric acid to paraffin was 78/22, which was adopted in concentrate waste drying system of domestic nuclear power plants. The leaching test resulted in about 50% of the cumulative fraction leached for boric acid and cobalt, respectively. The specific gravity of waste form was 0.87 ［g/g］whose value was less than that of water because the weight loss of about 39% occurred after the water immersion test of ninety days. It was also observed that the waste form which had undergone ninety-day water immersion test exhibited the compressive strength of 203 psi (1.38 MPa).

• The Korean Journal of Physiology
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• 제10권1호
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• pp.49-54
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• 1976

The change of heart rates during Flack Test was observed in the pregnant women, $24{\sim}48$weeks, of gestational age, to analyze mechanical and neural regulatory factors in responses to the positive lung inflation. The results obtained were summarized as followings: 1) Endurance tine of Flack Test was 37.6 sec, in the nonpregnant women, and 25.1 sec. in the pregnant women. 2) When Flack Test was employed, heart rate was decreased in early stage of Flack Test in the pregnant women, while heart rate was increased in the nonpregnant women. 3) In the pregnant women bradycardia due to abdominal mechanical intervention in early stage of Flack Test was prominent, while tachycardia was found in the nonpregnant women. 4) During Flack Test, tachycardia due to sympathetic central reflex activation was observed immediately after bradycardia in early stage of Flack Test. 5) It may be noted that Flack Test employed in the present study is a useful model to evaluate and analyze the neural and mechanical abdominal intervention factor in response to the positive inflation of lung in pregnant women.