• Title/Summary/Keyword: t-z method

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A Convergence Study about Married Couples' Attitude toward Family-Birth according to the Spouse's Participation Range of Family-Birth (배우자의 가족분만 참여범위에 따른 부부의 가족분만에 대한 태도에 관한 융합연구)

  • Lee, Sun-Young;Oh, Sangeun
    • Journal of the Korea Convergence Society
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    • v.9 no.6
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    • pp.107-116
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    • 2018
  • Purpose: The purpose of the study was to assess married couples' attitude toward family-birth according to the range of spouse's participation in family-birth. Method: Data were obtained by the 54 couples who used to visited in order to participate on family-birth at two teritary women's hospital in G-city. Result: There was a significant difference in pregnant woman's attitude : the status of having a job(Z=-2.01, p=.044) & type of nuclear family(Z=-2.17, p=.029), planned pregnance(Z=-2.54, p=.011). The spouse who partly participated in the process of family-birth showed higher(t=2.30, p=.030) compared to the spouse who participated in the whole process of family-birth. Conclusion: The results of the study suggest that hospitals and women's hospitals should support pregnant woman's social work and encourage spouse who partly participation and develop education programs.

Reliability Prediction of Long-term Creep Strength of Gr. 91 Steel for Next Generation Reactor Structure Materials (미래형 원자로 구조 재료용 Gr. 91 강의 장시간 크리프 강도의 신뢰성 예측)

  • Kim, Woo-Gon;Park, Jae-Young;Yin, Song-Nan;Kim, Dae-Whan;Park, Ji-Yeon;Kim, Seon-Jin
    • Korean Journal of Metals and Materials
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    • v.49 no.4
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    • pp.275-280
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    • 2011
  • This paper focuses on reliability prediction of long-term creep strength for Modified 9Cr-1Mo steel (Gr. 91) which is considered as one of the structural materials of next generation reactor systems. A "Z-parameter" method was introduced to describe the magnitude of standard deviation of creep rupture data to the master curve which can be plotted by log stress vs. The larson-Miller parameter (LMP). Statistical analysis showed that the scattering of the Z-parameter for the Gr. 91 steel well followed normal distribution. Using this normal distribution of the Z-parameter, the various reliability curves for creep strength design, such as stress-time temperature parameter reliability curves (${\sigma}$-TTP-R curves), stress-rupture time-reliability curves (${\sigma}-t_{r}-R$ curves), and allowable stress-temperature- reliability curves ([${\sigma}$]-T-R curves) were reasonably drawn, and their results are discussed.

A study on the application of finite element method to analysis of the magnetic flux distribution characteristics of the tubular motor (Tubular motor의 자속분포 특성 해석을 위한 유한요소법 적용연구)

  • 임달호;임태빈
    • 전기의세계
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    • v.30 no.12
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    • pp.811-816
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    • 1981
  • In this paper, the finite element method is applied to find the flux distribution of the magnetic field in the end region of the tubular motor. In order to analyze two-dimensional flux distribution, the r-z domain to be analyzed is subdivided into 56 nodes, 84 elements. In the case of wt=O and .pi./2, the flux distribution is shifted to the edge with frequency (w) and time (t) increase in the edge and the air gap. It is proved that this study does fit the actual phenomena.

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Follow-up Results of Z-plate Fixation in the Thoracolumbar Burst Fracture (흉요추 방출성 압박골절의 Z-plate를 이용한 고정술후 추적검사 결과)

  • Shim, Byeoung-Su;Kim, Keun-Su;Lee, Jung-Chung
    • Journal of Korean Neurosurgical Society
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    • v.29 no.6
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    • pp.763-771
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    • 2000
  • Objectives : Thoracolumbar burst fractures(TBLF) result in not only compressive deformity of vertebral body but also spinal cord compression by bony fragments. Many thoracolumbar burst fractures demand both anterior decompression and intervertebral fusion. Most of spinal surgeons use anterior instrumentation for anteior intervertebral bony fusion. The use of Z-plate has been increased recently, however there has been only a few reports regarding its clinical long-term strength. We studied nineteen patients with TBLF to find out the long-term stability of Z-plate. Methods : We have operated 19 patients from March 1996 to August 1998. They were treated with anterior decompression through either a transthoracic, retroperitoneal extrapleural or retroperitoneal approach. Retropulsed bony fragments were removed completely by corpectomy. Iliac bone graft was used for interbody fusion in all of the cases. They were evaluated by plain X-ray films including flexion and extention lateral films. Cobbs angle was used to evaluate kyphotic and lateral wedging deformity. Results : Burst fractured sites were T11 in two, three T12, nine L1, and five L2. Mean follow-up duration was fifteen months. Preoperative average kyphotic angle was 23.7 degree. Immediate postoperative kyphotic angle was 10.2 degree. Follow-up resluts of average kyphotic angles revealed 14 degrees. Four patients(21%), including two spinal 3-column injury, showed increasement of kyphotic angle more than 5 degree or breakage of intrumentation. Two patients showed the difference of kyphotic angle more than 3 degree. Five patients(26%) revealed lateral wedging deformity more than 3 degrees. Postoperative complications were two meralgia parestheticas, one pulmonary atelectasis and two donor site infections. Four of the eight patients, who initially showed incomplete spinal cord deficits, were nerologically improved by Frankel's grade. Conclusion : Z-plate fixation and iliac bone graft after anterior decompression in thoracolumbar burst fractures is a safe and easy method. Immediate postoperative results revealed excellent correction of posttraumatic kyphosis, but long-term follow-up evalution showed insufficient strength. Therefore we believe that use of Z-plate should be carefully decided, especially in the case of large lumbar fracture or 3-column injury.

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Priority Determination of the Projects for Ecological Restoration of the Stream : Case Study for Han River Estuary (생태하천 복원사업 우선순위 선정에 대한 연구: 한강하구를 중심으로)

  • Seonuk Baek;Junhak Lee;Seungmin Lee;Haneul Lee;Hung Soo Kim;Soojun Kim
    • Journal of Wetlands Research
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    • v.25 no.1
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    • pp.64-73
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    • 2023
  • Before 2022, there was a lot of confusion in the process of planning and implementing the projects for ecological restoration of the stream due to dualization the principal agent of stream management. Because the Ministry of Environment took charge of the project in 2022, securing the health of aquatic ecosystem of stream became an essential factor in the project. Therefore, in this study, the streams that require the project for ecological restoration was selected in Han River estuary, where it is essential to secure the health of the stream aquatic ecosystem as blackish water zone and Ramsar wetland are located. Physical, chemical, spatial/humanistic, health of aquatic ecosystems evaluation indexes were calculated based on the detailed facts and figures of the project for ecological restoration of the stream in the beginning. Ranking, re-scaling, z-score, and t-score normalization methods were applied to the calculated evaluation index, and the values were compared and analyzed. After that, the entropy weight method was applied to each evaluation index. Through this process, the streams(Mokgamcheon, Anyangcheon etc.) that require the project for ecological restoration were selected for the purpose of securing the health of the aquatic ecosystem in Han River estuary. The result of this study can be used as basic research data in the process of selecting the priority determination of the projects for ecological restoration of the stream.

A Study on the Effects of ET Training for the Development of Interpersonal Relationship and Self-Identity (인간관계 효율성 훈련이 간호대학생의 인간관계와 자아정체감에 미치는 효과)

  • Yoon, Yean-Hee;Koh, Myung-Suk
    • Journal of Korean Academy of Nursing Administration
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    • v.10 no.3
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    • pp.291-298
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    • 2004
  • Purpose: This study is to investigate if the effectiveness training program, suggested by Gordon(1970), could help these nursing students with the problems of interpersonal relationship and self-identification. Method: This study was designed using nonequivalent control group protest-posttest design. The subject for this study were thirty nursing students. Fifteen nursing students of the experimental group experienced the Effectiveness Training for 8 weeks (3 hours/week). The effect of Effectiveness Training was measured using Relationship Change Scale devised by Lee, H.D. & Moon, S.M.(1979) and Ego Identity Scale devised by Dignan(1965) which was translated by Seo, B.Y.(1975) Pretest data were collected by the researcher from both experimental and control group before training. After the end of eight weeks training, posttest data collected from both experimental and control group. Samples were analyzed using SPSS PC+. Result: 1. The first hypothesis, "level of interpersonal relationship of the experiment group after 8 weeks will be significantly higher than that of the control group"(z=-1.965, p=.049)was supported. 2. The second hypothesis, "level of ego-identity of the experimental group after 8 weeks will be significantly higher than that of the control group"(z=-2.191, p=.028)was supported. 3. The third hypothesis, "level of interpersonal relationship of the experiment group will be significantly higher than that of the control group after 4 months of training"(z=-.634, p=.238)was not supported. 4. The fourth hypothesis, "level of ego-identity of the experimental group will be significantly higher than that of the control group after 4 months of training"(z=-.292, p=.642)was not supported. Conclusion: The Effectiveness Training can be considered as an effective method of nursing students's interpersonal relationship & ego-identity, because it was proved to help nursing students increase level of their interpersonal relationship & ego-identity but it was needed to reinforce for continuing of the effect of the interpersonal relationship & ego-identity.

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A Simplified Numerical Method for Simulating the Generation of Linear Waves by a Moving Bottom (바닥의 움직임에 따른 선형파의 생성을 모의할 수 있는 간편 수치해석 기법)

  • Jae-Sang Jung
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.35 no.2
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    • pp.41-48
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    • 2023
  • In this study, simplified linear numerical method that can simulate wave generation and transformation by a moving bottom is introduced. Numerical analysis is conducted in wave number domain after continuity equation, linear dynamic and kinematic free surface boundary conditions and linear kinematic bottom boundary condition are Fourier transformed, and the results are expressed in space domain by an inverse Fourier transform. In the wavenumber domain, the dynamic free water surface boundary condition and the kinematic free water surface boundary condition are numerically calculated, and the velocity potential in the mean water level (z = 0) satisfies the continuity equation and the kinematic bottom boundary condition. Wave generation and transformation are investigated when the triangular and rectangular shape of bottoms move periodically. The results of the simplified numerical method are compared with the results of previous analytical solutions and agree well with them. Stability of numerical results according to the calculation time interval (Δt) and the calculation wave number interval (Δk) was also investigated. It was found that the numerical results were appropriate when Δt ≤ T(period)/1000 and Δk ≤ π/100.

An Improved Analytical Method for the Determination of Qualitative and Quantitative Characteristics of Di- and Trisaccharides in Honey using GC and GC/MS (GC 및 GC/MS에 의한 벌꿀 중의 이·삼당류 정성 및 정량 특성과 개선된 동시분석방법의 확립)

  • Kim, Jong-Bae;Jang, Eun-Suk;Kim, In-Suk;Lee, Hee-Jin;Lee, Hye-Jeong;Seo, Hyun-Sun;Park, Nam-Pyo
    • Korean Journal of Food Science and Technology
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    • v.47 no.1
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    • pp.27-36
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    • 2015
  • The improved analytical method with gas chromatography (GC) and GC-mass spectrometry was established to identify and quantify disaccharides and trisacchrides in honey. In this method, the analysis of trimethylsilyl (TMS), TMS-oxime and TMS-methoxime sugars takes into account the determination of a single peak of complete separation on the chromatogram. The number of possible peaks for the qualitative and quantitative determination of TMS, TMS-oxime, and TMS-methoxime sugars was 17, 22, and 25, respectively. This new analytical method allowed for the determination of diand trisaccharides in honey by TMS-oxime and TMS-methoxime derivatives. This study suggested that the improved method is more suitable and precise than the other analytical methods for the simultaneous determination of sugars in honey.

平面應力 破壞靭性値 擧動에 관한 硏究

  • 송삼홍;고성위;정규동
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.11 no.3
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    • pp.376-385
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    • 1987
  • In this study, the plane stress fracture toughness and Tearing modulus are investigated for various crack ratios using the J integral. To evaluate the J integral and Tearing modulus, both experiments and estimation are used. The thickness of the low carbon steel specimens that is used in the experiments is 3mm. The type of specimen that is considered in the study is center-cracked-tension one. The measurements of crack length are performed by unloading compliance method. In the estimation of crack parameters such as the J integral and load line displacement, the Ramberg and Osgood stress strain law is assumed. Then simple formulas are given for estimating the crack parameters from contained yielding to fully plastic solutions. Obtained results are as follows; (1) When the crack ratio is in the range of 0.500 - 0.701, the plane stress fracture toughness is almost constant regardless of crack ratios. (2) The fracture toughness (J$\_$c/) and Tearing modulus (T) obtained are J$\_$c/=28.51kgf/mm, T=677.7 for base metal, J$\_$c/=31.85kgf/mm, T=742.0 for annealed metal. (3) Simpson's and McCabe's formulas which consider crack growth in estimating J integral are shown more conservative J and lower T than Rice's and Sumpter's. (4) Comparison of the prediction with the actual experimental measurements by Simpson's formula shows good agreement.

Short-Term Complications of Percutaneous Endoscopic Gastrostomy according to the Type of Technique

  • Gang, Mi Hyeon;Kim, Jae Young
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.17 no.4
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    • pp.214-222
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    • 2014
  • Purpose: The method of percutaneous endoscopic gastrostomy (PEG) tube placement can be divided into the pull and introducer techniques. We compared short-term complications and prognosis between patients who underwent the pull technique and two other types of introducer techniques, the trocar introducer technique and T-fastener gastropexy technique. Methods: Twenty-six patients who underwent PEG were enrolled in this study. We retrospectively investigated the age, sex, body weight, weight-for-age Z-score, underlying diseases, PEG indications, complications, duration of NPO (nil per os), pain control frequency, and duration of antibiotic therapy. The patients were classified into three groups according to the PEG technique. The occurrence of complications was monitored for 10 weeks after the procedure. Results: The age, sex, body weight, and weight-for-age Z-score were not significantly between the three groups. Most patients had cerebral palsy and seizure disorders. Dysphagia was the most common indication for PEG. Major complications occurred in 5 (50%), 4 (66.7%), and 0 (0%) patients in group I, II, and III, respectively (p=0.005). Further, peristomal infection requiring systemic antibiotic therapy occurred in 2 (20%), 3 (50%), and 0 (0%) patients in group I, II, and III, respectively (p=0.04). There was no significant difference between the groups with respect to minor complications, duration of NPO, pain control frequency, and duration of antibiotic therapy. Conclusion: The results indicate that the T-fastener gastropexy technique was associated with the lowest rate of major complications.