119,148 research outputs found
Yoon named to National Academy of Engineering
No full textRoe-Hoan Yoon, who holds the Virginia Tech Nicholas T. Camicia Professorship, is a newly elected member of the National Academy of Engineering-the highest honor provided to members of the engineering profession
Analytical description of an asymmetric yield function (Yoon2014) by considering anisotropic hardening under non-associated flow rule
No full textA simple analytical form for yield surface distortion under non-associated flow rule is developed from the expression of the transformed second and third deviatoric stress invariants in Yoon et al. (2014). The developed analytical yield criterion has the same ability as the original yield criterion to describe material's strength differential (SD) effect. Compared with Yoon et al. (2014) criterion, the material parameters in the analytical form presented in this study can be directly calculated from the tension and compression stresses along 0 degrees, 45 degrees, 90 degrees and equi-biaxial directions, which doesn't need any optimization process and interpolation to describe the evolution of asymmetric yield surface under the proportional loadings. The proposed yield criterion can accurately predict the anisotropic hardening along 0 degrees, 45 degrees, 90 degrees and equi-biaxial directions under tension and compression, which will make the significant improvements in the stress predictions including 15 degrees, 30 degrees, 60 degrees and 75 degrees. To guarantee the convexity of yield surface during loading history, the minimum order of principal minor determinant is checked. The proposed yield criterion has been successfully applied for HCP materials to validate its general applicability for describing anisotropy/asymmetry-induced distorted yield surface during deformation. In addition, an analytical asymmetric plastic potential function is developed based on Poly4 yield function. The accuracy of the proposed plastic potential function for r-value evolution under tension and compression has been verified by applying it to different materials.
Letter, [Author unclear] to Paulina T. Merritt
No full textHandwritten letter to Paulina Merritt from an unknown author, October 1, 1876.
Yoon honored for contributions to minerals and metallurgical research
No full textRoe-Hoan Yoon, the Nicholas T. Camicia Professor of Mining and Minerals Engineering in the College of Engineering, has received one of the highest honors awarded by the Society for Mining, Metallurgy, and Exploration (SME)
We the people of Singapore
No full textThe song was first sung on 6 February 1969 to commemorate Singapore’s 150th Anniversary. T. R. Doraisamy was the Principal and Leong Yoon Pin was the lecturer of TTC
Nitrous oxide reduction by an obligate aerobic bacterium Gemmatimonas aurantiaca strain T-27
No full textN2O-reducing organisms with nitrous oxide reductases (NosZ) are known as the only biological sink of N2O in the environment. Among the most abundant nosZ genes found in the environment are nosZ genes affiliated with the understudied Gemmatimonadetes phylum. In this study, a unique regulatory mechanism of N2O reduction in Gemmatimonas aurantiaca strain T-27, an isolate affiliated with the Gemmatimonadetes phylum, was examined. Strain T-27 was incubated with N2O and/or O2 as the electron acceptor. Significant N2O reduction was observed only when O2 was initially present. When batch cultures of strain T-27 were amended with O2 and N2O, N2O reduction commenced after O2 was depleted. In a long-term incubation with the addition of N2O upon depletion, the N2O reduction rate decreased over time and came to an eventual stop. Spiking of the culture with O2 resulted in the resuscitation of N2O reduction activity, supporting the hypothesis that N2O reduction by strain T-27 required the transient presence of O2. The highest level of nosZ transcription (8.97 nosZ transcripts/recA transcript) was observed immediately
after O2 depletion, and transcription decreased 25-fold within 85 h, supporting the observed phenotype. The observed difference between responses of strain T-27 cultures amended with and without N2O to O2 starvation suggested that N2O helped sustain the viability of strain T-27 during temporary anoxia, although N2O reduction was not coupled to growth. The findings in this study suggest that obligate aerobic microorganisms with nosZ genes may utilize N2O as a temporary surrogate for O2 to survive periodic anoxia
Chang, Yoon-Jeong
No full text학위논문(석사)--아주대학교 보건대학원 :보건학과,2007.2본 연구는 고혈압환자에게 제공한 포괄적 교육프로그램이 고혈압관련 자기효능감, 건강행위이행정도에 미치는 효과를 파악하기 위한 동등성 대조군 사전·사후 설계를 이용한 실험연구이다. 자료수집기간은 2006년 7월 4일부터 8월 8일까지 H시 보건소를 이용하는 고혈압환자로 약물복용을 하는 대상자였으며, 포괄적 교육프로그램은 하루 2시간 주 1회 총 4주간 실시하였다.
자기효능감을 측정하는 도구는 박영임(1994)이 개발한 고혈압 관리와 관련된 건강행위 수행에 대한 자신감의 정도에 대한 척도를 이용하였으며, 건강행위이행 측정도구는 이영휘(1994)가 개발한 본태성고혈압 환자의 주관적 자가 간호와 관련된 수행정도를 측정하는 도구를 이용하였다.
본 연구의 전산통계 처리한 결과를 요약하면 다음과 같다.
제1가설인 “포괄적 교육프로그램을 받은 실험군은 포괄적 교육프로그램을 받지 않은 대조군보다 고혈압관련 자기효능감이 높을 것이다.” 는 지지되었다(t=11.91, p=.00).
제2가설인 “포괄적 교육프로그램을 받은 실험군은 포괄적 교육프로그램을 받지 않은 대조군보다 고혈압관련 건강행위 이행정도가 높을 것이다.” 는 지지되었다(t=16.20, p=.00).
이상의 결과로 보건소를 이용하는 고혈압환자를 대상으로 실시한 포괄적 교육프로그램은 환자의 고혈압관련 자기효능감, 건강행위 이행정도를 증진시키는데 효과가 있었으므로, 고혈압환자의 관리프로그램으로 활용할 수 있다고 본다.
본 연구의 결과를 근거로 향후 생활습관의 변화를 확인할 수 있는 장기적인 추후연구가 필요하며, 자기효능감을 증진시킬 수 있는 다양한 시청각 자료를 이용한 교육프로그램의 개발 및 다양한 분야에서의 연령별, 대상자별 차별화된 효과적인 포괄적인 교육프로그램의 개발을 제언한다.제 1장. 서론 = 1
1. 연구의 필요성 = 1
2. 연구의 목적 = 3
3. 연구문제 = 3
4. 연구가설 = 3
5. 용어정의 = 3
제 2장. 문헌고찰 = 5
1. 자기효능감의 개념 = 5
2. 자기효능감에 영향을 미치는 요인 = 6
3. 교육과 자기효능감 = 7
4. 건강행위이행과 혈압과의 관계 = 8
제3 장. 연구방법 = 10
1. 연구설계 = 10
2. 자료수집절차 = 10
3. 포괄적 교육프로그램 = 11
4. 연구대상자 = 12
5. 연구도구 = 12
6. 자료수집방법 및 절차 = 13
7. 자료분석방법 = 13
제 4장. 연구결과 = 14
1. 연구대상자의 특성 = 14
2. 가설검증 = 16
제 5장. 논의 = 20
제 6장. 결론 및 제언 = 23
1. 결론 = 23
2. 제한점 및 제언 = 24
참고문헌 = 26
부록 = 30
Abstracts = 36MasterThe purpose of the present study was to identify the effects of a comprehensive education program on the self-efficacy and health behavior performance in patients with hypertension. This study was an experimental study which used an equivalent control group pre-post test design.
Data was collected from July 4, 2006 to August 8, 2006. Subjects were recruited from a public health center in H city. The comprehensive education program was performed for 2 hours per a week for four times.
The first hypothesis, "the experimental group who received the comprehensive education program would have more self-efficacy than the control group who did not receive comprehensive education program," was statistically significant(t=11.91, p=.00).
The second hypothesis "the experimental group who received the comprehensive education program would show a better degree of performance of hypertension-related health behavior than the control group who didn't receive comprehensive education program," was statistically significant(t=16.20, p=.00).
These results suggest that the comprehensive education program was effective on the improvement of hypertension-related self-efficacy and the health behavior performance. It is recommended to develop the education program using other materials, such as audio-visual materials, and to apply them for hypertension patients who are in various ages
Absorption spectra of two-level atoms interacting with a strong polychromatic pump field and an arbitrarily intense probe field
No full text©1999 The American Physical Society
URL: http://link.aps.org/abstract/PRA/v60/p2547
DOI: 10.1103/PhysRevA.60.2547
PACS: 42.50.Gy, 32.80.-t, 42.50.HzA numerical method is introduced that solves the optical Bloch equations describing a two-level atom interacting with a strong polychromatic pump field with an equidistant spectrum and an arbitrarily intense monochromatic probe field. The method involves a transformation of the optical Bloch equations into a system of equations with time-independent coefficients at steady state via double harmonic expansion of the density-matrix elements, which is then solved by the method of matrix inversion. The solutions so obtained lead immediately to the determination of the polarization of the atomic medium and of the absorption and dispersion spectra. The method is applied to the case when the pump field is bichromatic and trichromatic, and the physical interpretation of the numerically computed spectra is given. [S1050-2947(99)10409-8].This research was supported in part by the Ministry of Science and Technology of Korea under Contract No. KRISS-98-0401-001 and by the Korea Atomic Energy Research Institute. One of the authors (T. H. Yoon) thanks Dr. S. A. Pulkin and J. R. Park for stimulating discussions
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