• Title/Summary/Keyword: stability period

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The Stability of Yin-Yang Temperament in Middle School Students (중학생에 있어서 음양 기질의 안정성)

  • Lee, Soo Jin;Chae, Han
    • Journal of Sasang Constitutional Medicine
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    • v.31 no.1
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    • pp.94-101
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    • 2019
  • Objectives The Yin-Yang construct was shown to have stable internal reliability or consistency using Sasang Personality Questionnaire (SPQ) throughout the various ages, however the study of stability over specific period of time was only conducted using adults. The purpose of the study was to examine the stability across the time using middle school students whose physical and psychological characteristics were most rapidly changing. Methods The 122 middle school students (65 boys and 57 girls) completed the SPQ at 1st year and 2nd year with one-year time difference. Cronbach's ${\alpha}$ and Pearson's correlation analysis were employed in order to show the internal consistency and stability over one-year interval after considering sex difference. Results The internal consistency of SPQ-T, SPQ-B, SPQ-C, SPQ-E using Cronbach's ${\alpha}$ were .61, .72, .28, .28 in 2016 and .62, .72, .26, .46 in 2017. The one-year test-retest reliability of SPQ-T, SPQ-B, SPQ-C, SPQ-E using Pearson's correlation analysis were .56, .61, .31, .23 in boys and .58, .63, .64, .29 in girls. Conclusion The current study showed the stability of Yin-Yang temperament across the one-year time suggesting that the Yin-Yang temperament is quite stable and measurable concept and the SPQ would be considered as an objective and reliable personality assessment.

Improvement in microbial stability of photosynthetic bacteria via optimized cell immobilization and lyophilization: Application to the treatment of shrimp aquaculture water

  • Kyoung Sook, Cho;Joong Kyun, Kim
    • Journal of Marine Bioscience and Biotechnology
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    • v.14 no.2
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    • pp.112-123
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    • 2022
  • Photosynthetic bacteria (PSB) play an important role in water purification, and their application is beneficial for sustainable aquaculture. However, maintaining the microbial stability of PSB from subculturing to preservation is a challenging task. Since improvement in the microbial stability of PSB is a crucial parameter, optimized conditions for cell immobilization and lyophilization were investigated. In PSB immobilization, 0.1-M CaCl2 was found to be the most effective divalent metal ion solution in terms of cost-effectiveness, resulting in beads with a 4-mm diameter and high loading (1.91×109 CFU/mL) of viable cells. Maintenance of cell viability, external appearance, and color of PSB beads was best in 3.5% NaCl during storage. In lyophilization, the addition of skim milk (9%) and dextrose (2%) as cryoprotective additives allowed the highest cell viability. Over an 18-week shrimp breeding period, when optimally manufactured beads and lyophilized powder of PSB were applied to shrimp aquaculture water, NH4+, NO3-, and NO2- were more effectively removed by 55%, 100%, and 100%, respectively, compared to controls. Thus, microbial stability of PSB through optimized cell immobilization and lyophilization was successfully enhanced, enabling a wide application.

Mesh Stability Study for the Performance Assessment of a Deep Geological Repository Using APro

  • Hyun Ho Cho;Hong Jang;Dong Hyuk Lee;Jung-Woo Kim
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.21 no.2
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    • pp.283-294
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    • 2023
  • APro, developed in KAERI for the process-based total system performance assessment (TSPA) of deep geological disposal systems, performs finite element method (FEM)-based multiphysics analysis. In the FEM-based analysis, the mesh element quality influences the numerical solution accuracy, memory requirement, and computation time. Therefore, an appropriate mesh structure should be constructed before the mesh stability analysis to achieve an accurate and efficient process-based TSPA. A generic reference case of DECOVALEX-2023 Task F, which has been proposed for simulating stationary groundwater flow and time-dependent conservative transport of two tracers, was used in this study for mesh stability analysis. The relative differences in tracer concentration varying mesh structures were determined by comparing with the results for the finest mesh structure. For calculation efficiency, the memory requirements and computation time were compared. Based on the mesh stability analysis, an approach based on adaptive mesh refinement was developed to resolve the error in the early stage of the simulation time-period. It was observed that the relative difference in the tracer concentration significantly decreased with high calculation efficiency.

Real-time hybrid substructuring of a base isolated building considering robust stability and performance analysis

  • Avci, Muammer;Botelho, Rui M.;Christenson, Richard
    • Smart Structures and Systems
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    • v.25 no.2
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    • pp.155-167
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    • 2020
  • This paper demonstrates a real-time hybrid substructuring (RTHS) shake table test to evaluate the seismic performance of a base isolated building. Since RTHS involves a feedback loop in the test implementation, the frequency dependent magnitude and inherent time delay of the actuator dynamics can introduce inaccuracy and instability. The paper presents a robust stability and performance analysis method for the RTHS test. The robust stability method involves casting the actuator dynamics as a multiplicative uncertainty and applying the small gain theorem to derive the sufficient conditions for robust stability and performance. The attractive feature of this robust stability and performance analysis method is that it accommodates linearized modeled or measured frequency response functions for both the physical substructure and actuator dynamics. Significant experimental research has been conducted on base isolators and dampers toward developing high fidelity numerical models. Shake table testing, where the building superstructure is tested while the isolation layer is numerically modeled, can allow for a range of isolation strategies to be examined for a single shake table experiment. Further, recent concerns in base isolation for long period, long duration earthquakes necessitate adding damping at the isolation layer, which can allow higher frequency energy to be transmitted into the superstructure and can result in damage to structural and nonstructural components that can be difficult to numerically model and accurately predict. As such, physical testing of the superstructure while numerically modeling the isolation layer may be desired. The RTHS approach has been previously proposed for base isolated buildings, however, to date it has not been conducted on a base isolated structure isolated at the ground level and where the isolation layer itself is numerically simulated. This configuration provides multiple challenges in the RTHS stability associated with higher physical substructure frequencies and a low numerical to physical mass ratio. This paper demonstrates a base isolated RTHS test and the robust stability and performance analysis necessary to ensure the stability and accuracy. The tests consist of a scaled idealized 4-story superstructure building model placed directly onto a shake table and the isolation layer simulated in MATLAB/Simulink using a dSpace real-time controller.

Comparison of between Upper Thoracic Manipulation and Cervical Stability Training on Range of Motion and Neck Disability in Patients with Chronic Mechanical Neck Pain (상부등뼈도수교정과 목뼈부위안정화운동이 만성 목뼈부위 기계학적 통증 환자의 관절가동범위와 장애지수에 미치는 효과 비교)

  • Lee, Byoung-Kwon;Yang, Jin-Mo;Kang, Keung-Hwan
    • Journal of the Korean Society of Physical Medicine
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    • v.10 no.2
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    • pp.35-45
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    • 2015
  • PURPOSE: The aim of this study is to investigate how upper thoracic manipulation and cervical stability training affects cervical range of motion and neck disability index of patients with chronic mechanical neck pain. METHODS: 30 patients with chronic mechanical neck pain, and randomly divided into the upper thoracic manipulation and the cervical stability training group. Upper thoracic manipulation group was conducted to the upper thoracic manipulation, and cervical stability training was conducted to the cervical stability training. Intervention period was 6 weeks, and 3 sessions, each of which was run for 5~10 minutes. The subjects were measured neck range of motion before and after intervention by electro-goniometer. Neck disability index was used to measure neck disability index Korean version. RESULTS: Comparison within groups, there were significant difference in neck range of motion before and after intervention, and Neck disability index significantly reduced in the cervical stability training group. The comparison between groups, there were no significant difference in neck range of motion and neck disability index. CONCLUSION: Upper thoracic manipulation and cervical stability training to the patients with chronic neck pain was helpful to improve neck range of motion and cervical stability training was helpful to improve neck disability index.

Large-Scale Slope Stability Analysis Using Climate Change Scenario (2): Analysis of Application Results (기후변화 시나리오를 이용한 광역 사면안정 해석(2): 결과분석)

  • Oh, Sung-Ryul;Lee, Gi-Ha;Choi, Byoung-Seub;Lee, Kun-Hyuk;Kwon, Hyun-Han
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.3
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    • pp.1-19
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    • 2014
  • This study aims to assess the slope stability variation of Jeonbuk drainage areas by RCM model outputs based on A1B climate change scenario and infinite slope stability model based on the previous research by Choi et al.(2013). For a large-scale slope stability analysis, we developed a GIS-based database regarding topographic, geologic and forestry parameters and also calculated daily maximum rainfall for the study period(1971~2100). Then, we assess slope stability variation of the 20 sub-catchments of Jeonbuk under the climate change scenario. The results show that the areal-average value of safety factor was estimated at 1.36(moderately stable) in spite of annual rainfall increase in the future. In addition, 7 sub-catchments became worse and 5 sub-catchments became better than the present period(1971~2000) in terms of safety factor in the future.

Numerical Analysis of the Stability of a Tailings Dump Slope using Field Monitoring Results (현장 모니터링 결과를 이용한 광미 적치사면 안정성의 수치해석적 연구)

  • Song, Young-Suk
    • The Journal of Engineering Geology
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    • v.27 no.1
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    • pp.21-29
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    • 2017
  • Variations in matric suction were compared between field measurements and numerical analysis for a tailings dump slope. We performed an analysis of slope stability using precipitation records measured in the field, selecting the period (72 hours) of highest rainfall intensity during the field monitoring, for which the matric suction and rainfall records measured in the field were analyzed. In addition, we applied the precipitation records of this period to the numerical analysis. SEEP/W and SLOPE/W were used to analyze the seepage flow in the slope due to rainfall and to investigate the slope stability considering the wetting front depth from the ground surface, respectively. The seepage analysis, using SEEP/W, was carried out on the rainfall data obtained in the field. Comparisons between the field monitoring data and simulation results for matric suction show some quantitative difference but similar patterns of temporal variation. According to the results of slope stability analysis using SLOPE/W and the results of seepage analysis, the safety factor of the slope showed a sudden increase at the point of rapid increase in rainfall intensity. It then recovered because subsequent rainfall was scarce. Therefore, the stability of the tailings dump slope can be reasonably estimated if seepage and slope stability analyses, based on precipitation records, have been carried out.

A Study on the Relationship of Wounds in the Growth Period, Inferiority Complex, Personality Disorder and Mental-Health among Secondary Students (중·고등학생의 성장과정 상처와 열등감, 성격장애, 정신건강과의 관계 연구)

  • Man-pyo Lee
    • Korean Journal of Culture and Social Issue
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    • v.18 no.4
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    • pp.505-532
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    • 2012
  • The purpose of this study was to examine the relationship among the growth period wounds, inferiority complex and personality disorder of teenaged students, which affected their mental health. The subjects in this study were 2,110 secondary students. After a survey was conducted, the collected data were analyzed. Whether there would be any differences among the adolescents in those factors were analyzed, and multiple regression analysis and path analysis were carried out. As a result, there were relatively more significant problems with the growth period wounds, inferiority complex, personality disorder and mental health of the students who were girls, who were high schoolers, whose household economy was more vulnerable and whose academic standing was lower. The growth period wound that exerted the largest significant influence on inferiority complex was happiness, followed by wound of security and wound of recognition, and the growth period wound that had the greatest significant impact on personality disorder was happiness, followed by wound of security, wound of confidence, wound of love and wound of equity. The growth period wound that exercised the biggest influence on mental health was happiness, followed by wound of security, wound of confidence, wound of love and wound of equity. As for the influence of the variables related to mental health, the indirect effects of the growth period wounds through personality disorder and inferiority complex were greater than their direct effects. The findings of the study suggest that growth period wounds are likely to lead to inferiority complex and personality disorder and ultimately to the injury of mental health, and indicate the importance of healthy family environments and of educational environments in the growth period.and mental health was analyzed, there was a statistically significant positive(+) correlation among all the variables. Third, the wound factors related to happiness and stability were identified as the factors that affected inferiority complex among the growth period wound factors. Personality disorder was found to be under the influence of the wound factors related to happiness, stability, love, confidence and a sense of equality in the growth period, and mental health was found to be affected by the wound factors related to happiness, stability, confidence, love and a sense of equality. Fourth, the growth period wounds had a direct impact on mental health, and inferiority complex played a significant mediating role at that time. Every subfactor of personality disorder also produced significant mediating effects except the wound factor of pride. The above-mentioned findings suggest that every possible effort should be made to let secondary students get hurt less to promote their mental health and resolve their mental health problems, and that professional counseling intervention and institutional assistance are required to help them to remove their inferiority complex and personality disorder.

Effects of Calorie Restriction on Microsomal Mixed Function Oxidase System and Free Radical in Kidney of SAMP8 Mice

  • kim, Hyun-Jeong;Choi, Jin-Ho;Rhee, Soon-Jae
    • Nutritional Sciences
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    • v.7 no.4
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    • pp.189-195
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    • 2004
  • 1bis study investigated the antioxidative effect in kidney of senescence-accelerated prone SAMP8 mice with calorie restriction. 4-weeks-old SAMP8 female mice were divided into 4 groups according to the experimental feeding period: for 4, 8, 12 month, and at natural death. Each group was subdivided into 2 groups, with thirteen mice each one, as ad libitum group and as dietary restriction group (60% of ad libitum feeding amount). After feeding for a given period, the mice were sacrificed to get the following results: among the experimental groups, there wereno significant differences in xanthine oxidase (XOD) activity in their kidney tissues. The contents of cytochrome $P_{450}$ decreased in ad libitum group and dietary restriction group by age. The activity of NADPH-cytochrome $P_{450}$ reductase showed a trend similar to cytochrome $P_{450}$. Superoxide radical content increased with age. At the 4th, 8th and 12 months of the experimental period, the activity in the dietary restriction group was less than that of ad libitum group by as much as 17% 14% and 14% respectively. For hydrogen peroxide, the contents were increased in the ad libitum group with age, while no correlation between content and age was observed in the dietary restriction group. In the 8th and 12th months of the experimental period, the were in the dietary restriction group less than that of ad libitum group counterpart as much as 17% and 20o/c, respectively. For the cellular membrane stability of the kidney, no significant correlation with age was observed in either the dietary restriction group or the ad libitum group. However at the 12th month of the experiment, however, the stability in the dietary restriction group was 11 % higher than that in the ad libitum group. In conclusion, with these results obtained from the SAMP8 mouse model, we demonstrate that dietary restriction has the effects of anti-oxidation and anti-senescence in the kidney.

Quantification, Anti-inflammatory and Antioxidant Effects of Mahwang-tang Decoction According to the Storage Temperature and Period (보관 온도 및 기간에 따른 마황탕 전탕액의 지표 성분 함량, 항염증 및 항산화 활성 비교)

  • Lee, Nari;Ha, Hyekyung;Shin, Hyeun-Kyoo;Seo, Chang-Seob
    • Korean Journal of Pharmacognosy
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    • v.49 no.2
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    • pp.172-181
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    • 2018
  • This study was designed to investigate the stability for chemical contents and biological activities of Mahwang-tang (MT) depending on the preservation temperature and periods. MT decoction pouches were preserved for 3 months at room temperature (RT, $23{\pm}1^{\circ}C$) and refrigeration ($4^{\circ}C$). To evaluate the stability of MT decoction, pH and sugar content were estimated. High-performance liquid chromatography analysis were performed to quantify the contents of marker compounds in MT. Anti-inflammatory effects of MT were evaluated to suppress the generation of nitric oxide, prostaglandin $E_2$ and cytokines (tumor necrosis $factor-{\alpha}$ and interleukin-6) in the RAW 264.7 cells stimulated with lipopolysaccharide. Total antioxidant capacity of MT was determined by ABTS radical scavenging activity. The pH of storage method and period showed a tendency to decrease gradually with time. There were no changes in sugar content depending on the preservation temperature and periods of MT decoction. Among the major components of MT, cinnamaldehyde was reduced time-dependently for 3 months of storage at RT. The inflammatory effect and antioxidant capacity of MT were reduced time-dependently at both RT and $4^{\circ}C$. Our results suggest that the preservation period of MT decoction is recommended in refrigeration within 3 months or less rather than at RT.