• Corrosion Science and Technology
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• 제15권5호
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• pp.245-252
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• 2016

The pipelines and equipments are degraded by flow-accelerated corrosion (FAC), and a large-scale test facility was constructed for simulate the FAC phenomena in secondary coolant environment of PWR type nuclear power plants. Using this facility, FAC test was performed on weld pipe (carbon steel and low alloy steel) at the conditions of high velocity flow (> 10 m/s). Wall thickness was measured by high temperature ultrasonic monitoring systems (four-channel buffer rod type and waveguide type) during test period and room temperature manual ultrasonic method before and after test period. This work deals with the complex effects of flow velocity on the wall thinning in weld pipe and the test results showed that the higher flow velocity induced different increasement of wall thinning rate for the carbon steel and low alloy steel pipe.

• Journal of Power Electronics
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• 제19권5호
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• pp.1087-1098
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• 2019

In this paper, a detuning factor (DeFac) method is proposed to design the key parameters for optimizing the transfer power and efficiency of an Inductively Coupled Power Transfer (ICPT) system with primary-secondary side compensation. Depending on the robustness of the system, the DeFac method can guarantee the stability of the transfer power and efficiency of an ICPT system within a certain range of resistive-capacitive or resistive-inductive loads. A MATLAB-Simulink model of a ICPT system was built to assess the system's main evaluation criteria, namely its maximum power ratio (PR) and efficiency, in terms of different approaches. In addition, a magnetic field simulation model was built using Ansoft to specify the leakage flux and current density. Simulation results show that both the maximum PR and efficiency of the ICPT system can reach almost 70% despite the severe detuning imposed by the DeFac method. The system also exhibited low levels of leakage flux and a high current density. Experimental results confirmed the validity and feasibility of an ICPT system using DeFac-designed parameters.

• Journal of Astronomy and Space Sciences
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• 제36권3호
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• pp.133-147
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• 2019

Challenging Minisatellite Payload (CHAMP) satellite magnetic data are used to investigate the latitudinal variation of the storm-time meso-scale field-aligned currents by defining a new metric called the FAC range. Three major geomagnetic storm events are considered. Alongside SymH, the possible contributions from solar wind dynamic pressure and interplanetary magnetic field (IMF) $B_Z$ are also investigated. The results show that the new metric predicts the latitudinal variation of FACs better than previous studies. As expected, the equatorward expansion and poleward retreat are observed during the storm main phase and recovery phase respectively. The equatorward shift is prominent on the northern duskside, at ${\sim}58^{\circ}$ coinciding with the minimum SymH and dayside at ${\sim}59^{\circ}$ compared to dawnside and nightside respectively. The latitudinal shift of FAC range is better correlated to IMF $B_Z$ in northern hemisphere dusk-dawn magnetic local time (MLT) sectors than in southern hemisphere. The FAC range latitudinal shifts responds better to dynamic pressure in the duskside northern hemisphere and dawnside southern hemisphere than in southern hemisphere dusk sector and northern hemisphere dawn sector respectively. FAC range exhibits a good correlation with dynamic pressure in the dayside (nightside) southern (northern) hemispheres depicting possible electrodynamic similarity at day-night MLT sectors in the opposite hemispheres.

• 대한물리의학회지
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• 제6권1호
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• pp.1-8
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• 2011

Purpose : The purpose of this study was to find out the effect of closed kinetic chain exercise with functional electrical stimulation(FES) of the gluteus medius on gait in stroke. Methods : 30 hemiplegic patients voluntarily participated in this study. Subjects were divided into experimental group(n=15) and control group(n=15). Experimental group was given closed kinetic chain exercise with FES of the gluteus medius and control group was given only closed kinetic chain exercise for 4 weeks. All subjects were measured 10m-walking speed, cadence, functional walking category(FAC) and modified motor assessment scale(MMAS) before and after intervention. Results : In experimental group, gait velocity, cadence, FAC and MMAS showed significant difference between pre and post test(p<.05). In control group, gait velocity, cadence and FAC showed significant difference between pre and post test(p<.05). Before intervention, gait velocity, cadence, FAC and MMAS were not significant difference between experimental group and control group(p>.05), but after intervention, gait velocity, FAC and MMAS were significant difference(p<.05). Conclusion : This study show that closed kinetic chain exercise with functional electrical stimulation(FES) of the gluteus medius is beneficial intervention for increase the wlking ability in stroke.

• Asian Pacific Journal of Cancer Prevention
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• 제13권3호
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• pp.941-944
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• 2012

Objective: The aim of current study was to evaluate the changes of health-related quality of life (HRQoL) and its clinical, demographic and socioeconomic determinants during chemotherapy and 4 months follow-up in women with breast cancer using a repeated measures framework. Methods and Materials: A double blind cohort study was performed in 100 breast cancer patients given fluorouracil, doxorubicin and cyclophosphamide (FAC) or docetaxel, doxorubicin, cyclophosphamide (TAC) in south of Iran. HRQoL was assessed at baseline, end of chemotherapy and four months thereafter using the QLQ-C30 questionnaire from European Organization for Research and Treatment of Cancer (EORTC). Generalized estimating equations (GEE) was applied for statistical analysis. Results: The mean of age at baseline was $48.5{\pm}10.6$. 70% and 14% of patients were married and smokers, respectively, and 20% suffered from another disease besides breast cancer. The results of GEE showed that after control for baseline scores, the HRQoL significantly improved over time. Although, the patients in FAC group had higher scores than the TAC group, the differences also diminished over time. Smoking, marital status and having child affected some scales of HRQoL. None of other variables were significantly related to HRQoL. Conclusion: Although patients in TAC groups had lower level of HRQoL over 8 months follow up, they experienced faster improvement than the FAC group. This implies that in long-term, improvements in TAC group are higher than FAC. Having children was positively correlated with HRQoL. Generally, there were no demographic and socio-economic differences in HRQoL in these patients between the chemotherapeutic regimens.

• Bulletin of the Korean Chemical Society
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• 제23권3호
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• pp.447-453
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• 2002

In this paper we have presented the results of thermodynamic, structural, and dynamic properties of model systems for liquid benzene, toluene and p-xylene in an isobaric-isothermal (NpT) ensemble at 283.15, 303.15, 323.15, and 343.15 K using molecular dynamics (MD) simulation. This work is initiated to compensate for our previous canonical (NVT) ensemble MD simulations [Bull. Kor. Chem. Soc. 2001, 23, 441] for the same systems in which the calculated pressures were too low. The calculated pressures in the NpT ensemble MD simulations are close to 1 atm and the volume of each system increases with increasing temperature. The first and second peaks in the center of mass g(r) diminish gradually and the minima increase as usual for the three liquids as the temperature increases. The three peaks of the site-site gC-C(r) at 283.15 K support the perpendicular structure of nearest neighbors in liquid benzene. Two self-diffusion coefficients of liquid benzene via the Einstein equation and via the Green-Kubo relation are in excellent agreement with the experimental measures. The self-diffusion coefficients of liquid toluene and p-xylene are in accord with the trend that the self-diffusion coefficient decreases with increasing number of methyl group. The friction constants calculated from the force auto-correlation (FAC) function with the assumption that the fast random force correlation ends at time which the FAC has the first negative value give a correct qualitative trends: decrease with increase of temperature and increase with the number of methyl group. The friction constants calculated from the FAC's are always less than those obtained from the friction-diffusion relation which reflects that the random FAC decays slower than the total FAC as described by Kubo [Rep. Prog. Phys. 1966, 29, 255].

• The Journal of Korean Physical Therapy
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• 제21권4호
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• pp.37-42
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• 2009

Purpose: The purpose of this study was to determine the effect of physical performance on bone mineral density (BMD) in elderly women. Methods: Twenty-one elderly women participated in this study. After testing functional ambulation category (FAC), they were classified into two groups: dependent walking group, those who could not walk independently (FAC 0~2, n=11) and independent walking group those who could walk independently (FAC 3~5, n=10). Outcome measures were: general characteristics, physical performance and BMD. General characteristics included age, body mass index (BMI) and waist-hip ratio. Physical performance included the chair rise test (CRT) and the modified fall efficacy scale (MFES). BMD was represented in the osteoporosis index (OI), T-score and Z-score. BMD was evaluated in calcaneal bone, using OsteoPro. The data was analyzed using SPSS 12.0 software and the Mann-Whitney U test and the Spearman correlation. Results: Age, BMI and waist hip ratio, which all affect BMD, showed no significant differences between groups (p>0.05). But the FAC 3~5 group showed a significantly higher score for CRT, MFES and T-score, compared with the FAC 0~2 group (p<0.05). The T-score was correlated with CRT and MFES scores (p<0.05). Conclusion: There is a positive relationship between physical performance and BMD. Therefore, improved physical performance can have a beneficial effect by reducing osteoporosis in elderly women, considering a positive relationship between physical performance and BMD.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.692-700
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• 1996

The objective of this study is to develop a systematic purification plant using the metabolism of aerobic microorganisms. This system is subsequently aerated and continuously removes suspended solids and settling sludges caused by aerating pressure at the bottom of a lower pipe (i.e., Continuous Removal of Suspended solids and Settling sludges, CRSS). The CRSS plants are brought out by introducing fine air bubbles into the liquid phase of a lower pipe in the bio-reactor. These plant uses aeration pipe, with multiple inlets to sweep the floor of bio-reactor tank, instead of the conventional scraper mechanisms. The principal advantage of this system is that it can continuously remove very small or light particles that settles completely within a short time. Once the particles have been floated to the surface, they can be moved into the pipe and collected in the settling tank by sequently aerated pressure. The experimental results shows that about 99.0% of the biochemical oxygen demand(BOD), 99.3% of the suspended solid(SS), 92.3% of the total nitrogen(T-N), 99.0% of the turbidity(TU), 100% of the total coliform(TC)and ammonia was respectively removed during aerobic digestion for 9 days. These result indicates that the CRS S plants are very effective for reduction and deodorization of swine wastewater contaminants, and the efflux from CRS S can either be discharged in the river or used as nutrient solution of formulation for plant growth factories. The developed CRSS plant proved to be flexible and it can simply be adapted to any type of biological waste treatment problem.roblem.

• 플랜트 저널
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• 제9권4호
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• pp.26-30
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• 2013

유동가속부식에 의해 배관이 파손된 500 MW급 A 복합발전소 배열회수보일러 저압증기발생기 배관을 모델로 삼아 배관급수 내의 용존산소 부족이 유동가속부식의 주요 원인임을 도출하고 용존산소를 증가시키기 위해 적용된 하이드라이진 차단 수처리에 대한 적용효과를 분석하였다. 수처리 적용 1년 후 급수의 용존산소는 0.15 ppb에서 3~5 ppb로 상승되고, 산화환원전위도 -245 mV에서 170 mV로 산화성으로 상승되었다. 또한 유동가속부식에 의한 부식생성물인 철분함유량은 18.5 ppb에서 5~7 ppb로 감소되었다. 따라서 하이드라이진 차단 수처리로 급수의 용존산소가 증가되며 유동가속부식에 의한 배관의 부식생성물인 철분함유량이 감소됨을 확인하였다.

• 산업식품공학
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• 제13권3호
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• pp.216-220
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• 2009

Aloe gel의 동결건조에 농축도가 서로 다른 액상 시료를 사용하였을 때 건조분말의 기능성 변화를 비교분석하였다. Aloe의 많은 기능성 중에서 유효 다당류의 농도, 기능성 작용기에 대한 FT-IR 특성, Jack bean urease 저해 효과, FAC(fat adsorption capacity)를 대상으로 하였다. 농축도가 높은 경우에 유효 다당류의 농도, urease 저해 효과, FAC 모두 상대적으로 크게 나타났다. FT-IR의 분석에서는 농축도가 높은 경우에 glucomannan의 acetyl 기에 대한 spectrum 영역인 1600-1550 $cm^{-1}$와 1450-1400 $cm^{-1}$에서 흡광도가 크게 관찰되었다. 결과적으로 Aloe gel의 동결건조시 전처리과정인 농축 공정에서는 농축도가 높을수록 유효다당류의 양과 acetyl기 함량의 수준이 크며, 간접적으로 urease 저해 효과에 따른 Helicobacter pylori의 억제 및 FAC의 증가 효과를 보였다.