• Title/Summary/Keyword: Pressure support

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Difference in Adolescent's Academic Motivation by Family Strengths and Parent's Expectation Styles (가족건강성과 부모의 학업기대유형에 따른 청소년 학습동기의 차이)

  • Oh, Myeong-Hee;Jang, Yoon-Ok
    • Journal of Korean Home Economics Education Association
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    • v.19 no.4
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    • pp.57-74
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    • 2007
  • The purpose of this study was to investigate differences in adolescent's academic motivation, which is composed of intrinsic learning motivation and extrinsic learning motivation, by family strengths and parent's expectation styles. The subject of this study were 508 students who were selected at random from second, and third grade of middle school in Daegu. Factor analysis and MANOVA were employed for data analysis and Scheff test for post - hoc analysis. The main findings of this study were as follows: First, there were significant differences in learning motivation of adolescents according to the degree of family strengths. More specifically, adolescents who perceived their family strengths to be high had higher intrinsic learning motivation than adolescents who perceived their family strengths to be middle and low. Second, there were significant differences in intrinsic learning motivation of adolescents according to the parent's academic expectation styles. Adolescents who perceived their parent's academic expectation styles paternal support-maternal support, paternal pressure-maternal support, and paternal support-maternal pressure showed higher intrinsic learning motivation than adolescents who perceived their parent's academic expectation styles paternal pressure-maternal pressure. Third, there were significant differences in intrinsic learning motivation of adolescents according to the parent's academic expectation styles and the degree of family strengths. In adolescents group who perceived their family strengths to be low, adolescents who perceived their the parent's academic expectation styles to be paternal support-maternal support, paternal pressure-maternal support and paternal support-maternal pressure had higher intrinsic learning motivation than adolescents who perceived their the parent's academic expectation styles to be paternal pressure-maternal pressure.

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Analyses of Environmental and Psychological Factors for Academic Hatred: Focusing on the Senior Students in Korean High Schools (학업반감에 영향을 미치는 환경적·심리적 영향요인 분석: 고등학교 3학년 학생을 대상으로)

  • Lee, Minyoung;Uhm, Jeongho;Lee, Kyeong-Joo;Lee, Sangeun;Lee, Sang Min
    • Korean Journal of School Psychology
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    • v.16 no.2
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    • pp.89-110
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    • 2019
  • This study is to verify relative influence of individual, parent, peer, teacher-related variables as protective factors and risk factors of academic hatred. Surveys were conducted with 1,015 (women, 57.3%) high school third grade students across eight schools where are located in Seoul, Incheon, and Geyonggi province. Correlation analysis and hierarchical multiple regression analysis were performed. The findings are summarized as follows. Teacher's academic pressure did not have significant correlation with student's basic psychological needs, teacher's autonomy support, teacher's support, and peer support whereas other variables showed significant correlation each others. The hierarchical multiple regression analysis indicated that student's individual competence and autonomy, parent's academic support, and teacher's emotional support work as protective factors and that parent's academic pressure functions as a risk factor. The effects of peer support disappeared when teacher-related factors were included. In addition, the effects of teacher's autonomy support disappeared, while the effects of teacher's support strengthened when learner's basic psychological needs were input. This study is meaningful in that it clarified academic hatred which had not been studied in other research and that it provided theoretical foundation for subsequent studies on academic hatred by examining relative influence of related variables. Lastly, it presented its limitation, implications on intervening strategies in school counseling, and suggestions for later studies.

Factors That Influence the Adoption of the Internet Market (인터넷 상거래시장 진출결정에 영향을 주는 요인에 관한 연구)

  • 박흥국
    • The Journal of Information Systems
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    • v.8 no.2
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    • pp.129-143
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    • 1999
  • A great number of companies are currently examining the opportunities made available through the internet. This research aims to identify the factors that influence the adoption of the internet market. The innovation-IT-diffusion theory provide the theoretical foundation for this study. Seven factors were found to influence the adoption level of the internet market. They are top management support, cost efficiency, inclination toward new technology, absorptive capacity, institutional support, competitors move and customer pressure. Nonparametric test was used to test hypotheses. The results shows that top management support is the most important factor, and institutional support is not related to the adoption of the internet market.

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A Comparison of Clinical Efficacy of Weaning Method Between the Mode of Intermittent Mandatory Ventilation and Intermittent Mandatory Ventilation Plus Pressure Support (기계적 호흡 치료로부터의 이탈방법으로서 Intermittent Mandatory Ventilation 단독 사용과 Pressure Support를 병용한 Intermittent Mandatory Ventilation의 비교)

  • Choi, Jeong-Eun;Koh, Youn-Suck;Cho, Won-Kyoung;Lim, Chae-Man;Kim, Woo-Sung;Park, Pyung-Hwan;Choi, Jong-Moo;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.4
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    • pp.372-378
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    • 1994
  • Background: Pressure support ventilation(PSV) is a new form of mechanical ventilatory support that assists spontaneous inspiraory effort of an intubated patient with a clinician-selected amount of positive airway pressure. Low level pressure support during inspiration can overcome the resistive component of inspiratory work imposed by an endotracheal tube. However the clinical efficacy of PSV as a weaning method has not been established yet. Object: The aim of study was to evaluate the efficacy of PSV when it is added to intermittent mandatory ventilation(IMV) in facilitating weaning precess compaired to IMV mode alone. Method: When the subject patients became clinically stable with their arterial blood gas analysis in acceptable range, they underwent weaning process either by IMV alone or by IMV plus PSV. The level of pressure support was held constant throught the weaning period. For the patients who required mechanical ventilation for less than 72 hr, 2h weaning trial was performed with IMV rate starting from 6/min. For the patients who required mechanical ventilation more than 72 hr, 7 hr weaning trial was performed with IMV rate starting from 8/min. For the patients who failed three consecutive trials of weaning, retrial of weaning was attempted over 3 days with IMV rate starting from 8/min. Clinical characteristics, APACHE II score and nutritional status were compared. For all patients, heart rate, mean blood pressure and respiratory rate were mornitored for 48 hrs after weaning trial started. Results: The total number of weaning trial was 37 in 23 patients(18 by IMV, 19 by IMV+PSV). Total ventilation time, APACHE II score and nutritional status were not statistically different between the two groups. The weaning success rate were not statistically different(38.3% by IMV, 42.1% by IMV+PSV) and the changes of mean blood pressure, heart rate, respiratory rate during first 48 hours were not different between the two groups. Conclusion: Low level PSV when added to IMV for weaning trial does not seem to improve the success rate of weaning from mechanical ventilation. PSV at 10cm $H_2O$ did not induce significant physiologic changes during weaning process.

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Simulation study on porosity disturbance of ultra-large-diameter jet borehole excavation based on water jet coal wetting and softening model

  • Guo, Yan L.;Liu, Hai B.;Chen, Jian;Guo, Li W.;Li, Hao M.
    • Geomechanics and Engineering
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    • v.30 no.2
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    • pp.153-167
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    • 2022
  • This study proposes a method to analyze the distribution of coal porosity disturbances after the excavation of ultra-large-diameter water jet boreholes using a coal wetting and softening model. The high-pressure jet is regarded as a short-term high-pressure water injection process. The water injection range is the coal softening range. The time when the reference point of the borehole wall is shocked by the high-pressure water column is equivalent to the time of high-pressure water injection of the coal wall. The influence of roadway excavation with support and borehole diameter on the ultra-large-diameter jet drilling excavation is also studied. The coal core around the borehole is used to measure the gas permeability for determining the porosity disturbance distribution of the coal in the sampling plane to verify the correctness of the simulation results. Results show that the excavation borehole is beneficial to the expansion of the roadway excavation disturbance, and the expansion distance of the roadway excavation disturbance has a quadratic relationship with the borehole diameter. Wetting and softening of the coal around the borehole wall will promote the uniform distribution of the overall porosity disturbance and reduce the amplitude of disturbance fluctuations.

NATE터널의 갱문 가시설 배후 균열에 따른 조치 및 보강사례

  • Kil, Ho-Un;Kim, Jin-Hong;Yoo, Jai-Sung;Cha, Bok-Nam
    • 기술발표회
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    • s.2006
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    • pp.342-355
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    • 2006
  • The Tunnel portal is designed on temporary support system which is composed by 28m height H-Pile method and Ground Anchor method. The tunnel has excavated about 30m from the portal, but some deformation is found on the surface ground just above the tunnel face. It was investigated very carefully to find out the causes of deformation. By the observation and study, two main causes of deformation are found out. The one is earth pressure increase compared with classical earth pressure theory. That was due to the direction of ground rock mass's discontinuities. It causes the increase of earth pressure that are activated by the direction of discontinuity. The other one is that present design method neglect the transferred force by removal of temporary support members and ground anchor within the tunnel contour line as the tunnel excavation proceeds As the result of removals of the member and anchor, some force transferred from removed systems to remaining supporting systems. In designing the portal support systems, lt must be considered the discontiunity of ground mass and the transfered force due to excation.

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A Study on Concrete Lining Stress Changes Considering Load Supporting Capacity of Primary Supports of NATM Tunnel (NATM 터널에서 1차지보재의 지보압을 고려한 콘크리트라이닝 응력변화에 관한 연구)

  • Jeon, Sang Hyun;Shin, Young Wan;Yoo, Han Kyu
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.4C
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    • pp.147-154
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    • 2011
  • Currently NATM tunnels are designed by applying the initial ground loads caused during construction to the primary supports, conisting of shotcrete, steel ribs and rock bolts. For long term considerations, it is assumed that the primary supports lose its functionality and therefore the secondary support, i.e. concrete lining, is design to resist against the entire ground loads. But the steel ribs, usually applied to bad ground conditions, are embedded in shotcrete causing very little corrosion and therefore the assumption that the primary support will lose all of its functionality is too conservative. Also even though shotcrete carbonates in long term, excluding it from design is also too conservative. In this study, we have, through analytical and numerical analysis, set a rational level of support pressure and allowable relaxed rock mass height sustainable by the primary support for long term design. Changes in sectional forces of the concrete lining considering the calculated support pressure of the primary supports was also carried out. Shallow subway tunnels were considered in the analysis with weathered rock and soft rock ground conditions. The analysis results showed that, by considering the support pressure of steel ribs, an economical design of the concrete lining is possible.

Wind Tunnel Investigation of Fluctuating Pressure inside Building (풍하중에 의한 건물내부 압력의 동적변화에 관한 연구)

  • Kyoung-Hoon Rhee
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1990.10a
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    • pp.63-68
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    • 1990
  • The nature of fluctuating air pressure inside building was studied by testing a building model in a wind tunnel. The model has a single room and a sin81e window opening. Various opening conditions were tested in both laminar uniform wind and turbulent boundary-layer wind. The RMS and the spectra of the fluctuating internal pressure were measured. The test results support a recent theory which predicts the behavior of internal pressure under high wind based on aerodynamic analysis.

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Sloshing Impact Response Analysis for Insulation System of LNG CCS Considering Elastic Support Effects of Hull Structures (선체구조의 탄성지지 효과를 고려한 LNG 운반선 방열구조의 슬로싱 충격응답 해석법에 관한 연구)

  • Nho, In Sik;Ki, Min-Seok;Kim, Sung-Chan;Lee, Jang Hyun;Kim, Yonghwan
    • Journal of Ocean Engineering and Technology
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    • v.31 no.5
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    • pp.357-363
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    • 2017
  • The sloshing pressure acting on a membrane-type LNG CCS is a typical irregular impact load, and the structural response of a tank system induced by sloshing also shows very complex behavior, including fluid structure interaction. Therefore, it is not easy to accurately estimate the sloshing impact pressures and resulting structural response. Moreover, a huge time consuming process to deal with the enormous pressure data obtained during a model tank test and the following structural analysis would be inevitable. To reduce the computation time for structural analysis, in this study, a rational structural modeling strategy was considered, and a simplified scheme to analyze the dynamic structural responses of an LNG CCS was introduced, which was based on the concept of the linear combination of the triangular response functions obtained by a transient response analysis of structures under unit triangular impact pressure. A structural analysis of a real Mark III membrane type insulation system under the sloshing impact pressure time histories obtained by model tests was performed using the various proposed structural models and simplified analysis scheme. The results were investigated in detail, including the elastic support effects of the hull structure.

Reliability analysis of anti-seismic stability of 3D pressurized tunnel faces by response surfaces method

  • Zhang, Biao;Ma, Zongyu;Wang, Xuan;Zhang, Jiasheng;Peng, Wenqing
    • Geomechanics and Engineering
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    • v.20 no.1
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    • pp.43-54
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    • 2020
  • The limit analysis and response surfaces method were combined to investigate the reliability of pressurized tunnel faces subjected to seismic force. The quasi-static method was utilized to introduce seismic force into the tunnel face. A 3D horn failure mechanism of pressurized tunnel faces subjected to seismic force was constructed. The collapse pressure of pressurized tunnel faces was solved by the kinematical approach. The limit state equation of pressurized tunnel faces was obtained according to the collapse pressure and support pressure. And then a reliability model of pressurized tunnel faces was established. The feasibility and superiority of the response surfaces method was verified by comparing with the Monte Carlo method. The influence of the mean of soil parameters and support pressure, variation coefficients, distribution type and correlation of c-φ on the reliability of pressurized tunnel faces was discussed. The reasonable safety factor and support pressure required by pressurized tunnel faces to satisfy 3 safety levels were presented. In addition, the effects of horizontal seismic force, vertical seismic force and correlation of kh-kv on the reliability of pressurized tunnel faces were also performed. The method of this work can give a new idea for anti-seismic design of pressurized tunnel faces.