• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.114-132
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• 2011

We have proposed a new approach based on energy gradient concept for the study of flow instability and turbulent transition in parallel flows in our previous works. It was shown that the disturbance amplitude required for turbulent transition is inversely proportional to Re, which is in agreement with the experiments for imposed transverse disturbance. In present study, the energy gradient theory is extended to the generalized curved flows which have much application in turbomachinery and other fluid delivery devices. Within the frame of the new theory, basic theorems for flow instability in general cases are provided in details. Examples of applications of the theory are given from our previous studies which show comparison of the theory with available experimental data. It is shown that excellent agreement has been achieved for several configurations. Finally, various prediction methods for turbulent transition are reviewed and commented.

• Journal of Science and Technology Studies
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• v.15 no.1
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• pp.109-143
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• 2015

For continuous and successful innovation, changes in innovation system are required and have been magnified as a new controversy. With high public interest in changes of innovation system, Transition theory and policy in Netherlands are now attracting attentions of many researchers and policymakers. Transition policy in Netherlands is distinguished from existing policies for fundamental system change in that take remarkably different views and methods. Typical examples of transition in Netherlands are such as sustainable energy transition, biodiversity and natural resource transition, sustainable agriculture transition, and sustainable transportation. Transitions in Netherlands are still in the early stage of it but several positive effects are witnessing. However some problems - linking theory and practice, ambiguity of transition concept, linking long-term vision and short-term, resistance of existing regime, implementation problem, diffusion of support, etc.- to be tackled are still remaining. In spite of those problems, many lessons can be drawn from them. To guide structural changes in innovation system into the right path and cope with lock-in problem by existing system and regime, we need to learn from Transition theory and policy in Netherlands.

• Journal of Internet Computing and Services
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• v.17 no.5
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• pp.173-184
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• 2016

Prevalence of Agile methods in software companies is increasing dramatically. Software companies need to employ these methods to overcome the inherent challenges of traditional methods. However, transitioning to Agile approach is a topic of debate and there is no unique and well-defined transition model or framework yet. Although some research studies have addressed barriers and strengths behind the successful Agile deployment, it seems that this process still needs to be studied more in depth. The rationale behind this is the socio-technical nature of Agile transition and adoption. Particularly, the challenges and problems that software companies are facing during Agile transition, show that this process in more difficult than expected. Conducting a large-scale research study revealed that Agile transition and adoption process needs to be supported by several critical prerequisites. This study adopted a Ground Theory with the participation of 49 Agile experts from 13 different countries and empirically identified seven transition prerequisites. These prerequisites focus on the different aspects of the transition. The main aim of this paper is proposing these prerequisites and theoretical and practical implication of these prerequisites. Providing these prerequisites before moving to Agile increases chance of success in Agile transition and adoption and leads to fewer challenges during the change process.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.66 no.3
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• pp.129-134
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• 2017

We investigated theoretically the quantum optical transition properties of Si, in quasi 2-Dimensinal Landau splitting system, based on quantum transport theory. We apply the quantum transport theory (QTR) to the system in the confinement of electrons by square well confinement potential under linearly polarized oscillating field. We use the projected Liouville equation method with Equilibrium Average Projection Scheme (EAPS). In order to analyze the quantum transition, we compare the temperature and the magnetic field dependencies of the QTLW and the QTLS on four transition processes, namely, the intra-leval transition process, the inter-leval transition process, the phonon emission transition process and the phonon absorption transition process.

• Korean Journal of Oriental Medicine
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• v.11 no.1
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• pp.33-42
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• 2005

Traditional pharmacological theory was not built in a day. It had been changing in the past, still changing in the present day and will be changing in the future. The transition was made by criticism, modification and complements through countless debates. Therefore, we can learn the systematic stream of traditional pharmacology and logical construction and make an estimate of the changes in the future, by looking at the debates and the transition of pharmacological theory.

• Bulletin of the Korean Chemical Society
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• v.20 no.11
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• pp.1281-1287
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• 1999

The low-lying electronic states of diazirine and 3,3'-dimethyldiazirine have been studied by high level ab initio quantum chemical methods. The equilibrium geometries of the ground state and the first excited singlet and triplet states have been optimized using the Hartree-Fock (HF) and complete active space SCF (CASSCF) methods, as well as using the Møller-Plesset second order perturbation (MP2) theory and the single configuration interaction (CIS) theory. It was found that the first excited singlet state is of 1 B1 symmetry resulting from the n- π* transition, while the first excited triplet state is of 3 B2 symmetry resulting from the π- π* transition. The harmonic vibrational frequencies have been calculated at the optimized geometry of each electronic state, and the scaled frequencies have been compared with the experimental frequencies available. The adiabatic and vertical transition energies from the ground electronic state to the low-lying electronic states have been estimated by means of multireference methods based on the CASSCF wavefunctions, i.e., the multiconfigurational quasidegenerate second order perturbation (MCQDPT2) theory and the CASSCF second-order configuration interaction (CASSCF-SOCI) theory. The vertical transition energies have also been calculated by the CIS method for comparison. The computed transition energies, particularly by MCQDPT2, agree well with the experimental observations, and the electronic structures of the molecules have been discussed, particularly in light of the controversy over the existence of the so-called second electronic state.

• Advances in concrete construction
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• v.1 no.3
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• pp.239-252
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• 2013

Mortar microstructure is considered as a three-phase composite material, which is cement paste, fine aggregate and interfacial transition zone. Interfacial transition zone is the weakest link between the cement paste and fine aggregate, so it has a significant role to determine the properties of cementitious composites. In this study, specimens (w/c = 0.35, 0.45, 0.55) with various volume fractions of fine aggregate ($V_f$ = 0, 0.1, 0.2, 0.3 and 0.4) were cast and tested. To predict the equivalent migration coefficient ($M_e$) and migration coefficient of interfacial transition zone ($M_{itz}$), double-inclusion method and Mori-Tanaka theory were used to estimate. There are two stages to estimate and calculate the thickness of interfacial transition zone (h) and migration coefficient of interfacial transition zone ($M_{itz}$). The first stage, the data of experimental chloride ion migration coefficient ($M_s$) was used to calculate the equivalent migration coefficient of fine aggregate with interfacial transition zone ($M_e$) by Mori-Tanaka theory. The second stage, the thickness of interfacial transition zone (h) and migration coefficient of interfacial transition zone ($M_{itz}$) was calculated by Hori and Nemat-Nasser's double inclusion model. Between the theoretical and experimental data a comparison was conducted to investigate the behavior of interfacial transition zone in mortar and the effect of interfacial transition zone on the chloride migration coefficient, the results indicated that the numerical simulations is derived to the $M_{itz}/M_m$ ratio is 2.11~8.28. Additionally, thickness of interfacial transition zone is predicted from $10{\mu}m$, 60 to $80{\mu}m$, 70 to $100{\mu}m$ and 90 to $130{\mu}m$ for SM30, M35, M45 and M55, respectively.

• Journal of Korean Academy of Nursing
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• v.45 no.6
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• pp.919-927
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• 2015

Purpose: Effective transitional care is needed to improve the quality of life in older adult patients with chronic illness and avoid discontinuity of care and adverse events. The aim of this article is to provide an overview of the key features, broader implications, and the utility of Meleis' transition theory intended for the transitional care of older adults with chronic illnesses. We present the role of nurse in the context of transitional care and propose future directions to increase the quality of nursing care. Methods: The online databases Cumulative Index of Nursing and Allied Health Literature, MEDLINE, and Science Direct were searched for relevant literature published since 1970 along with textbooks regarding nursing theory. Results: An evaluation of the usefulness of transition theory based on transitional care in older adult patients with chronic illnesses is provided. Healthy transition should be the expected standard of nursing care for older adults across all healthcare settings. Conclusion: Nurses need to contribute to the development of transitional care for vulnerable populations; however, transition theory needs to be enhanced through additional theoretical work and repeated evaluations of the applicability in areas of transitional care.

• Korean Journal of Adult Nursing
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• v.26 no.4
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• pp.479-487
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• 2014

Purpose: This study was a grounded theory research aimed at generating a substantive theory that accounts for the explanatory social processes in which immigrant Korean single-mother families were engaged in the United States. Methods: In-depth interviews were conducted with 15 immigrant Korean single mothers who were living with children under 18 years of age at the time of the interviews. Data collection guided by theoretical sampling and concurrent constant comparative analysis of the transcribed data was conducted to identify the core social process. Results: The emerged core social process was "living for the children," which represented the driving process by which these women made transition to their new lives as single-mother families. The major task throughout the entire transition was re-creating their families. The women's transition involved practical and psychological transitions. The practical transition involved three stages: assuring family survival, struggling between the father role and the mother role, and stabilizing. The psychological transition involved becoming strong and settling in with a new supportive network. Conclusion: Study results added to the literature by elaborating the women's emphasis on maternal identity and the resilience-provoking nature of the women's transitions.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.235-238
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• 2006

This paper is about the code that realizes the $e^N$-Method for boundary-layer transition prediction. The $e^N$-Method based on the linear stability theory is applied to predicting boundary-layer transition frequently. This paper deals with the construction of code, stability analysis and the calculation of N-factor. The results of transition prediction using the $e^N$-Method for flat plate/cone compressible boundary-layers are presented.