• International Journal of Air-Conditioning and Refrigeration
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• v.13 no.1
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• pp.51-60
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• 2005

This paper reviews the studies on the pressure drop and the heat transfer in microchannels. Although a lot of studies about the single-phase flow have been done until now, conflicting results are occasionally reported about flow transition from laminar flow to turbulent flow, friction factor, and Nusselt number. Some studies reported the early flow transition due to relatively greater wall effect like surface roughness, but the other studies showed that the flow transition occurred at the Reynolds number of about 2300 and the early flow transition might be due to less accurate measurement of the channel geometry. Also, there have been arguments whether the conventional relation based upon continuum theory can be applied to the fluid flow and the heat transfer in microchannels without modification or not. The studies about the two-phase flow in microchannels have been mostly about investigating the flow pattern and the pressure drop in rectangular channels using two-component, two-phase flow like air/water mixture. Some studies proposed correlations to predict two-phase flow pressure drop in microchannels. They were mostly based on Lockhart-Martinelli model with modification on C-coefficient, which was dependent on channel geometry, Reynolds number, surface tension, and so on. Others investigated the characteristics of flow boiling heat transfer in microchannels with respect to test parameters such as mass flux, heat flux, system pressure, and so on. The existing studies have not been fully satisfactory in providing consistent results about the pressure drop and the heat transfer in microchannels. Therefore, more in-depth studies should be done for understanding the fundamentals of the transport phenomena in the microchannels and giving the basic guidelines to design the micro devices.

• The Research Journal of the Costume Culture
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• v.12 no.3
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• pp.429-440
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• 2004

The age after the French Revolution was the period of experiment and change in dress for both men and women. Directly after the close of the Reign of Terror, Directoire(1795-1799) became the extreme fashion known as incroyables and merveilleuses which mean 'impossible' or 'unimaginable'. This study aimed to investigate the sociocultural phenomena which affect to clothing change through the French Revolution period and clothing analysis of incroyables and merveillues. Furthermore, this study will contribute to establishing the theory of clothing culture and help predicting clothing change in accordance with social circumstances. Incroyables and merveilleuses represent extreme opposites in sleekness of attire and grooming. Incroyables required an unkempt, wrinkled appearance and a contrived carelessness. Merveilleuseses show the exaggerated transparency and simplicity in the fashions of female. Also, they devoted to the worship of the antique and the masculine fashions. This fashion madness appeared as the result of revolutionary social change. Their costume showed characteristics of the transition period between French Revolution and Classic period. However, they simply carried existing tendencies to the point of caricature by an enthusiastic overstatement.

• Korean Journal of Social Welfare Studies
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• v.42 no.1
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• pp.243-278
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• 2011

The main purpose of this paper is to understand the process of the poverty exit across generations through the live experience based on the grounded theory analysis of the in-depth interview. We find that poverty means a lack of achievement and freedom of agency that is a level of control about resource and situation. So exit of poverty across generations is the state that is not only to achieve functioning but also to recover capabilities. Based on this result, central phenomena of the intergenerational exit process of poverty are support from relation and continuous transition at each stage in life. Even if this central phenomenon is an important event, it has the incomplete attribute. Because support from relation is beyond individual scope of control and participants can't escape second labor market as they don't have enough time in the process of transition. Therefore, this paper suggests that the expansion of state welfare and strategy should support transition as policy priorities to minimize limitation of relation and risk of income loss.

• Journal of the Korean Chemical Society
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• v.44 no.6
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• pp.611-624
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• 2000

In this study we analysed 3-12 grade science textbooks, many literatures and internet sites related to diffusion and dissolution concepts. From these data, we discovered that the explanations of diffusion that used in textbooks are not considered the site of collision with mediums, and confused with dissolution, state transition and effusion. In the case of dissolution, almost analysis data were short of the explanations of interaction effect. Most of all, the focus of dissolution explanations was to solve the calculation problems rather than to understand the concept. Every internet site was poor, just as the level of showing textbook contents with computer, so the only effect of using computer was the sense of sight and hearing. Chemistry must be understood nature phenomena with a view point of particle theory, but many textbooks and Internet sites didn't represent it sufficiently. We set up the correct scientific concept and linked micro world of particle theory with macro world of nature phenomena. With a use of computer which have the advantage of representing moving things, we developed the computer-assisted instruction programs related to diffusion and dissolution with the viewpoint of particle movement.

• Journal of the Daesoon Academy of Sciences
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• v.24_1
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• pp.315-349
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• 2014

This paper was carried out to bring the researches on Cultivation Practice of Daesoonjinrihoe which have been at a standstill after analyzing the directions of studies on Cultivation Practice and diagnosing its problems, in addition to that, the paper was also conducted in a way of discussing the research directions in the future. This work enables scholars who have interests in Daesoon Thoughts to easily comprehend over the length and breadth of Cultivation Practice of Daesoonjinrihoe as well as help them understand what level of researches regarding Cultivation Practice has been demanded. Furthermore, this paper will be a step-stone for scholars to ponder how and on what perspective they approach a wide variety of studies on Daesoon Thoughts. The problems reflected on the previous researches on Cultivation Practice are summarized as follows: first, except a few researches in general, problem recognition, research target, style, method, and content are not diverged from the frame defined by Jang Byeong-Gil, who set it up in Daesoon Religion and Thought (Daesoon Jonggyo Sasang) in 1989. Proliferating overlapped researches without developing problem awareness is of great concern. And such researching climate has gradually set in. Secondly, there are numerous researches intending to reveal the researcher's forceful attitude implying faith. Thirdly, most of the previous researches neglect to focus on defining the range of researches. Fourthly, when defining concepts, more thorough insight is needed. Lastly, the researches on analysing symbols and attempting signification analysis are relatively few, only to find many errors. To solve these problems, this paper suggests to develop theories which back up Cultivation Practice by researching on the fields of theory of mind-nature(心性), theory of mind-qi(心氣), theory of pain, Religious Ethics, viewpoint of God/gods, and psychology. Secondly, all the symbols and meanings of elements shown in Cultivation Practice need analyzing more elaborately sophisticatedly and more in-depth. In order to fulfil this goal, by adapting the recent trends of historical studies, it is essential to attempt to engraft Cultivation Practice of Daesoonjinrihoe on cultural phenomena, to analyze thick layers of meanings beneath its surface, to interpret differently, utilizing various perspectives such as focusing on the gender problems, and to extract true meanings out of Cultivation Practice by analyzing everyday events which can occur in real cultivation practices. Thirdly, the terms and concepts regarding Cultivation Practice base the principle themselves. Fourthly, by utilizing methodology of comparative studies on religions, the comparative researches on cultivation practice of different religious traditions are also needed. Lastly, the history of aspects on Cultivation Practice such as transition of mantras, processes which have been conducted through proprieties of prayer and training should be collected and classified. In this context, this work is very important since it helps understand the aspects of transition of originality and characteristics in Cultivation Practice of Daesoonjinrihoe according to passage of time.

• Coupled systems mechanics
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• v.6 no.1
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• pp.41-54
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• 2017

Shape-memory alloys (SMA) have interesting behaviors and important mechanical properties due to the solid-solid phase transformation. These phenomena are dominated by the evolution of microstructures. In recent years, the microstructures in SMAs have been studied extensively and modeled using molecular dynamics (MD) simulations. However, it remains difficult to identify the crystal variants in the simulation results, which consist of large numbers of atoms. In the present work, a method is developed to identify the austenite phase and the monoclinic martensite crystal variants in MD results. The transformation matrix of each lattice is calculated to determine the corresponding crystal variant. Evolution of the volume fraction of the crystal variants and the microstructure in Ni-Ti SMAs under thermal and mechanical boundary conditions are examined. The method is validated by comparing MD-simulated interface normals with theoretical solutions. In addition, the results show that, in certain cases, the interatomic potential used in the current study leads to inconsistent monoclinic lattices compared with crystallographic theory. Thus, a specific modification is applied and the applicability of the potential is discussed.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.209.2-209.2
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• 2015

Two dimensional layered materials, such as transition metal dichalcogenides (TMDs) family have been attracted significant attention due to novel physical and chemical properties. Among them, molybdenum disulfide ($MoS_2$) has novel physical phenomena such as absence of dangling bonds, lack of inversion symmetry, valley degrees of freedom. Previous studies have shown that the interface of metal/$MoS_2$ contacts significantly affects device performance due to presence of a scalable Schottky barrier height at their interface, resulting voltage drops and restricting carrier injection. In this study, we report a new device structure by using few-layer graphene as the bottom interconnections, in order to offer Schottky barrier free contact to bi-layer $MoS_2$. The fabrication of process start with mechanically exfoliates bulk graphite that served as the source/drain electrodes. The semiconducting $MoS_2$ flake was deposited onto a $SiO_2$ (280 nm-thick)/Si substrate in which graphene electrodes were pre-deposited. To evaluate the barrier height of contact, we employed thermionic-emission theory to describe our experimental findings. We demonstrate that, the Schottky barrier height dramatically decreases from 300 to 0 meV as function of gate voltages, and further becomes negative values. Our findings suggested that, few-layer graphene could be able to realize ohmic contact and to provide new opportunities in ohmic formations.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.4
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• pp.751-760
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• 2009

Yoon Gil-Young(1911-1987) was a frontier of the field of Traditional Korean Medical Physiology(TKMP) who was academically active since mid 1950s until early 1970s. He wrote several important papers and books. Among his writings, "A Study on the Methodology of Traditional Korean Medical Physiology", which was published serially in the "Korean Oriental Medical Journal" from June 1966 until March 1967, played an important role in establishing the contemporary TKMP and showed his academic stance on Traditional Korean Medicine(TKM). This review will evaluate this paper's contribution to the establishment of TKMP in historical context, summarize the unique characteristics of his understanding of TKMP by analyzing the text, and then based on those information, examine his view on TKMP and TKM. Historically, this paper was written in transition period from the traditional TKM knowledge system to the modernized one. Aim of this paper was to provide a methodology for establishing TKMP as a scientific knowledge system like that of the western medicine. Based on his study of Yin-Yang theory and theory of five circuits and six qi in Huangdi's Internal Classics, he suggested those theories as methods to observing life phenomena and systematizing the observations. And he regarded these methods as of great value in determining the unique characteristics of TKM compared to those of western medicine. Through re-reading this paper, it was found that he had pride and confidence in the methodology of TKM, and also that he thought in scientizing and modernizing TKM it was very important to understand and efficiently put in use the methodology of TKM. It was also found that his view on TKMP and TKM was pro modernization.

• The Research Journal of the Costume Culture
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• v.16 no.2
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• pp.382-396
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• 2008

The purpose of this study is to analyze the transition of glamour style expressed in modern fashion throughout the history. The glamour style in modern fashion was categorized into five periods which are Hollywood glamour(H), Feminine glamour(F), Rich glamour(R), Decadent glamour(D), and Trash glamour(T). These categories were analyzed and compared in the viewpoint of aesthetic values deduced on the previous study. As a method of analysis, literature study and case study through the publications in aesthetics, history and preceding theses were used. The results of analysis are: Ostentatious luxury was suggested by extravagance of the movie star in H, the splendid American lifestyle in F, conspicuous consumption in R, fin de siecle bad taste in D and self-assured exposure in T. Mysterious idolatry was studied as exaggerated goddesshood of the movie star in H. It was expanded to celebrities including fashion models, television actresses, pop singers and young couture designers in the other periods. Artificial sensuality was originated from the femme fatale image of the courtesan as well as the traditional femininity of Victorian era in H. It was developed through exaggerated hourglass silhouette of the wife dressing in F. But an aggressiveness in R, a hyper-sexual femme fatale in D, an independent and defiant image of the showgirl in T were observed. Playful queerness stood out clearly by the fin de siecle phenomena. Though it was embodied in sexual perversive subculture, it emerged as hi fashion by young designers in the late R and became a crucial aesthetic value throughout D and T. It is more connected with the origins of glamour which arouses sexual ambiguity, crudity, aggressiveness and death. The continuity and discontinuity of the glamour style based on the theory of 'linked solution' were also analyzed.

• Korea-Australia Rheology Journal
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• v.19 no.4
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• pp.191-199
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• 2007

Precision injection molding process is of great importance since precision optical products such as CD, DVD and various lens are manufactured by those process. In such products, birefringence affects the optical performance while residual stress that determines the geometric precision level. Therefore, it is needed to study residual stress and birefringence that affect deformation and optical quality, respectively in precision optical product. In the present study, we tried to predict residual stress, final shrinkage and birefringence in injection molded parts in a systematic way, and compared numerical results with the corresponding experimental data. Residual stress and birefringence can be divided into two parts, namely flow induced and thermally induced portions. Flow induced birefringence is dominant during the flow, whereas thermally induced stress is much higher than flow induced one when amorphous polymer undergoes rapid cooling across the glass transition region. A numerical system that is able to predict birefringence, residual stress and final shrinkage in injection molding process has been developed using hybrid finite element-difference method for a general three dimensional thin part geometry. The present modeling attempts to integrate the analysis of the entire process consistently by assuming polymeric materials as nonlinear viscoelastic fluids above a no-flow temperature and as linear viscoelastic solids below the no-flow temperature, while calculating residual stress, shrinkage and birefringence accordingly. Thus, for flow induced ones, the Leonov model and stress-optical law are adopted, while the linear viscoelastic model, photoviscoelastic model and free volume theory taking into account the density relaxation phenomena are employed to predict thermally induced ones. Special cares are taken of the modeling of the lateral boundary condition which can consider product geometry, histories of pressure and residual stress. Deformations at and after ejection have been considered using thin shell viscoelastic finite element method. There were good correspondences between numerical results and experimental data if final shrinkage, residual stress and birefringence were compared.