• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.743-752
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• 2019

The flow in the meandering channel is characterized by the spiral motion of secondary currents that typically cause the erosion along the outer bank. Hydraulic structures, such as spur dike and groyne, are commonly installed on the channel bottom near the outer bank to mitigate the strength of secondary currents. This study is to investigate the effects of submerged vanes installed in a $90^{\circ}$ meandering channel on the development of secondary currents through three-dimensional numerical modeling using the hybrid RANS/LES method for turbulence and the volume of fluid method, based on OpenFOAM open source toolbox, for capturing the free surface at the Froude number of 0.43. We employ the second-order-accurate finite volume methods in the space and time for the numerical modeling and compare numerical results with experimental measurements for evaluating the numerical predictions. Numerical results show that the present simulations well reproduce the experimental measurements, in terms of the time-averaged streamwise velocity and secondary velocity vector fields in the bend with submerged vanes. The computed flow fields reveal that the streamwise velocity near the bed along the outer bank at the end section of bend dramatically decrease by one third of mean velocity after the installation of vanes, which support that submerged vanes mitigate the strength of primary secondary flow and are helpful for the channel stability along the outer bank. The flow between the top of vanes and the free surface accelerates and the maximum velocity of free surface flow near the flow impingement along the outer bank increases about 20% due to the installation of submerged vanes. Numerical solutions show the formations of the horseshoe vortices at the front of vanes and the lee wakes behind the vanes, which are responsible for strong local scour around vanes. Additional study on the shapes and arrangement of vanes is required for mitigate the local scour.

• Journal of Wetlands Research
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• v.24 no.4
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• pp.345-353
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• 2022

A wastewater treatment plant (WWTP) is a major gateway for the engineered nano-particles (ENPs) entering the water bodies. However existing studies have reported that many WWTPs exceed the No Observed Effective Concentration (NOEC) for ENPs in the effluent and thus they need to be designed or operated to more effectively control ENPs. Understanding and predicting ENPs behaviors in the unit and \the whole process of a WWTP should be the key first step to develop strategies for controlling ENPs using a WWTP. This study aims to provide a modeling tool for predicting behaviors and removal efficiencies of ENPs in a WWTP associated with process characteristics and major operating conditions. In the developed model, four unit processes for water treatment (primary clarifier, bioreactor, secondary clarifier, and tertiary treatment unit) were considered. Additionally the model simulates the sludge treatment system as a single process that integrates multiple unit processes including thickeners, digesters, and dewatering units. The simulated ENP was nano-sized TiO₂, (nano-TiO₂) assuming that its behavior in a WWTP is dominated by the attachment with suspendid solids (SS), while dissolution and transformation are insignificant. The attachment mechanism of nano-TiO₂ to SS was incorporated into the model equations using the apparent solid-liquid partition coefficient (Kd) under the equilibrium assumption between solid and liquid phase, and a steady state condition of nano-TiO₂ was assumed. Furthermore, an MS Excel-based user interface was developed to provide user-friendly environment for the nano-TiO₂ removal efficiency calculations. Using the developed model, a preliminary simulation was conducted to examine how the solid retention time (SRT), a major operating variable affects the removal efficiency of nano-TiO₂ particles in a WWTP.

• Journal of the Korean Electrochemical Society
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• v.24 no.3
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• pp.52-64
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• 2021

The effect of Fe and BO₃ doping on structure, thermal, and electrical properties of Li_1+xFe_xTi_2-x(PO₄)_3-y(BO₃)_y (x = 0.2, 0.5)-based glass and glass ceramics was investigated. In addition, their crystallization behavior during sintering and ionic conductivity were also investigated in terms of sintering temperature. FT-IR and XPS results indicated that Fe²⁺ and Fe³⁺ ions in Li_1+xFe_xTi_2-x(PO₄)_3-y(BO₃)_y glass worked as a network modifier (FeO₆ octahedra) and also as a network former (FeO₄ tetrahedra). In the case of the glass with low substitution of BO₃, boron formed (PB)O₄ network structure, while boron preferred BO₃ triangles or B₃O₃ boroxol rings with increasing the BO₃ content owing to boic oxide anomaly, which can result in an increased non-bridging oxygen. The glass transition temperature (GTT) and crystallization temperature (CT) was lowered as the BO₃ substitution was increased, while Fe²⁺ lowered the GTT and raised the CT. The ionic conductivity of Li_1+xFe_xTi_2-x(PO₄)_3-y(BO₃)_y glass ceramics were 8.85×10^-4 and 1.38×10^-4S/cm for x = 0.2 and 0.5, respectively. The oxidation state of doped Fe and boric oxide anomaly were due to the enhanced lithium ion conductivity of glass ceramics.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.4
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• pp.124-136
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• 2011

In landscape architecture, plants play an important role in realizing the intention of the architect and user- behavior as well as an ecology and appearance of the space for them. However, it is true that many researches have focused on ecological characteristics of plants, their cultivation environment and symbolic meanings in traditional terms, while relatively few for the analysis of the aspects of each period through plants. For this, cherry trees that we often see around are selected and their introduction, propagation, development and symbolism from the view of chronicle are studied and the results are followings; Firstly, three-year seedlings of 1,500 pieces of cherry tree from Osaka and Tokyo were planted for the first time in Oieseongdae, Namsan Park, Seoul. Since then, they had been widely planted at traditional sites, modern parks, newly-constructed roads for street trees, and for this, the Japanese Government-General of Chosun had actively supported by its direct cultivation and selling of cherry trees. The spread of cherry trees planted raised the question of whether or not Prunus yedoensis is originated from Jeju Island. Secondly, such massive and artificial planting of them had become attractions over the time and mass media at that time also had actively promoted it. And such trend made the day and night picnic under the cherry blossoms one of the most representative cultures of enjoying spring in Seoul. Thirdly, although general people enjoyed cherry blossoms, but they had dual view and attitude for cherry trees, which were well expressed in their use of them: for example, cherry blossoms, aeng and sakura were used altogether for same meaning, but night aeng or night picnic under cherry blossoms were especially used instead of yojakura when mentioning just pleasure, which meant some saw night enjoying cherry blossoms a low culture. Fourth, symbolic space of Chosun had been transformed into the space for enjoyment and consumption. Anyone who paid entrance fee could enjoy performance of revugirl, cinema and entertainment along with enjoying cherry blossoms. The still-existing strict differentiation of enjoyment culture by social status, class and ethnicity was dismantled from that trend and brought about a kind of disorder. From this, we could find that cherry blossoms had made a great contribution to the change of traditional enjoyment culture over the Japanese colonial period and become a popular spring enjoyment.

• (The)Study of the Eastern Classic
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• no.72
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• pp.67-95
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• 2018

Gyeong-san(經山) Jeong Won-yong(鄭元容, 1783~1873) passed the state examination in 1802(純祖 2), and he has been in office for about 70 years. Jeong Won-yong with excellent administrative ability, he was an important figure in the Sedo politics, and was recognized by many writers for his outstanding writings. Nevertheless, his research results are small. This paper studyed his literary theories as a preliminary to look at Jeong Won-yong's literature in general After examining the features of Jeong Won-yong, there were three main aspects. First, Jeong Won-yong had a negative view of imitation. In particular, he stressed that he should oppose the attitude of unconditionally following Go-in(古人) without considering his capabilities and express his intention. Second, Jeong Won-yong pursued Jin-ui(眞意) when he wrote a poem. He thought rather than think that it is important to decorate a poem, it is important that emotion is exposed to the poem in a natural way. And he tried to unfold his individuality in the poem without copying others. Because if he imitate someone else when he write a poem, it is hard to express his thinking. His negative view of imitation and he pursued Jin-ui(眞意) are closely related. Lastly, Jeong Won-yong considered records important. Jeong Won-yong's record spirit is deeply related to his government service life. Jeong Won-yong who had been in government service all his life, hoped his experience would help manage the country. That's why he thought records were very important. And through this recording behavior, he wanted to get help later on. So it seems that he left a vast works.

• 기호학연구
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• no.54
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• pp.119-145
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• 2018

This paper attempts to divide the narrative into three levels and review the approach methodology to understand Princess Bari as a narrative. If the stratification of the narrative, the analysis of each levels, and the integrated approach to them are made, this can contribute to suggesting new directions and ways to understand and study Princess Bari. The story level of Princess Bari, the surface structure, is shaped by the space movement and the chronological sequential structure of the life task that started from the birth of the main character. This story shows how a woman who was denied her existence by her father as soon as she was born finds an ontological transformation and identities through a process. Especially, the journey of finding identity is mainly formed through the events that occur through the relationship with family members. This structure, which can be found in the narrative level, forms a deep structure with the oppositional paradigm of family members' conflict and reconciliation, life and death. The thought structure revealed in this story is the problem of life is the problem of family composition, and the problem of death is also the same. In response to how to look at the unified world of coexistence of life and death, this tradition group of myths makes a relationship with man and God. This story is mainly communicated in the Korean shamanistic ritual(Gut) that sent the dead to the afterlife. Although the shaman is the sender and the participants in the ritual are the receivers, the story is well known a message that does not have new information repeated in certain situations. In gut, the patrons and participants do not simply accept the narrative as a message, but accept themselves as codes for reconstructing their lives and behavior through autocommunication. By accepting the characters and events of as a homeomorphism relationship with their lives, people accept the everyday life as an integrated view of life and death, disjunction and communication, conflict and reconciliation, and the present viewpoint. It can not change the real world, but it changes the attitude of 'I' about life. And it is a change and transformation that can be achieved through personal communication like the transformation of Princess Bari into god in myth. Thus, Princess Bari shows that each meaning and function in the story level, composition level, and communication level is related to each other. In addition, the structure revealed by this narrative on three levels is also effective in revealing the collective consciousness and cultural system of the transmission group.

• New Physics: Sae Mulli
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• v.68 no.12
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• pp.1293-1301
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• 2018

The basic magnetic properties of commercially available High-$T_c$ Superconductor (HTS) GdBCO-coated conductor (GdBCO-CCs) were investigated by using physical property measurement system-vibrating sample magnetometer (PPMS-VSM). From the zero-field-cooled (ZFC) m(T) curve, the $T_c$ was found to be ~93 K. After removing the background m(H) data, we obtained both the net m(H) data and the ${\Delta}m_{irr}$. The $H_{irr}(T)$ coincided very well with the power-law relation $H_{irr}=H_{irr}(0)(1-T/T_c)^n$ with $$n{\sim_=}1.19$$. The magnetic flux behavior was investigated by using the ${\delta}$ values in the relationship $J_c{\propto}{\Delta}m_{irr}{\propto}H^{-{\delta}}$. A ${\delta}{\approx}0$ region denoting an independent magnetic flux pinning effect, a ${\delta}{\approx}0.6{\sim}1.2$ region representing a collective flux pinning effect due to the interaction, and a ${\delta}{\gg}2$ region representing freely moving magnetic fluxes caused by the Lorentz force were observed. The boundary line between ${\delta}{\approx}0$ and ${\delta}{\approx}0.6{\sim}1.2$ is denoted by a $H_1$, and the one between ${\delta}{\approx}0.6{\sim}1.2$ and ${\delta}{\gg}2$ is denoted by a $H_2$. The ${\delta}(T)$ was obtained in the region of $H_1$ < H < $H_2$. As the temperature was decreased, the ${\delta}$ value gradually decreased.

• The Journal of Korean Philosophical History
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• no.50
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• pp.37-74
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• 2016

Song Joon Kil(宋浚吉, 1606-1672) intended to establish the subjectivity of people as a "Great Justice". He declared that at that time "Great Justice" was meant to respect 'Ming(明)' and reject 'Ching'(淸). He understood 'Ching' as a country which destroyed the human community and reasoned that if we put Ching's uncivilized behavior out of our mind in favor of the pursuit of present existence and merits, a temporary peace may be got but eternal peace and stability would not be achieved. 'Ming' doesn't refer only to the name of a country, but a country with the capacity to perform 'humanity and justice' with a human culture. On the other hand, he considered 'Ching' to signify the uncivilised country that destroyed or repressed the humanity and peaceful order of the world. He thought the international order can only be maintained under the organization respectful and protective of humanity. He believed a country should act to unify the whole world guaranteeing life and stability. He possessed this cultivated spirit which acted to protect the civilised world from the perils of an uncivilised world. But because of the great famine for a lot of years and the international state(Ming was regressing, and Ching was continuing to make rapid strides) was timely unsuitable to revenge and to wash the shame off. So Song propeled to stabilize the government and to strengthen the national ethics. Song focused on administering the domestic affairs. To him a high priority was a internal affairs, and a low priority was a external affairs[military aggression]. Song considered 'providing for the welfare of the people'(安民) before 'pushing ahead with military aggression'(外攘). And a high priority was 'restoring the people'(養民), a low priority was 'the military affairs'(治兵). Song regarded 'domestic affairs'(內治) as a fundamental affairs. He putted 'to nurse people'(養民) and 'to straighten King's mind'(格君心) first, than 'to buildup military'. His foreign policy was 'respecting Ming' and 'rejecting Ching'. Song was bothered about defining Chosun dynasty's moral obligations to the southern Ming government(1644~46) at Nanjing at that time.

• The Journal of Korean Philosophical History
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• no.23
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• pp.217-244
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• 2008

This research studied Minor Annotation of Elementary Learning("小學枝言") and Private Examination of Classic of the Mind("心經密驗") from the ethical perspective. Minor Annotation of Elementary Learning and Private Examination of Classic of the Mind are writings that play a role of bridge between Chinese classics(經學) and Theory of Statecraft(經世論). These two essays were written for the purpose of putting virtue into practice, which had been attained by studying Chinese classics, through a vehicle called Theory of Statecraft. If Minor Annotation of Elementary Learning called as a book of cultivation of outward morality or outward behavior, then Private Examination of Classic of the Mind is the book for cultivation of inward temperament. The 'practice' emphasized by Dasan through these two essays denotes ceaseless efforts toward goodness or virtue. Such efforts can be interpreted as 'ethical practice', if looked at from the perspective of aggressive struggle toward virtue. Dasan, in these two essays, had stressed to practice Good(善) through positive and lively actions. The matter of Good and Bad(善惡) in humans is not associated with their mind, but related to their practice. That is to say, humans may turn out to be good through means of 'ethical practice'. For Dasan, 'ethical practice' toward Good should have to be continued and upheld not only in the course of self-cultivation, but also in 'establishing relationship' with others. Such an assertion of Dasan was to lay emphasis on accomplishment of 'ethical practice' toward Good amid close relationship between personal and social ethics. Also, Dasan had emphasized free will(自由意志) in humans. This means that Good and Bad will be determined according to humans' free will, and to the same extent, that humans are responsible for its consequence. It is noted that Dasan had stressed that any human having free will should have to be a 'man of virtue'(君子) through means of 'ethical practice'.

• (The)Study of the Eastern Classic
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• no.49
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• pp.393-430
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• 2012

In this paper, Bowen's family therapy from the perspective of the theory, narrative analysis of Korean novels, three Regis - tration Subsection.Bowen's description of the individual's behavior is causing problems within the family of anxiety and self-differentiation using two variables. The home if problems or conflicts expressed in these works, the figures showed that the undifferentiated ego at the center of the problem. Undifferentiated ego character felt extreme anxiety when their alienation from the relationship of the family-oriented jeokjangja Undifferentiated ego to relieve anxiety and to consolidate their position in the family relationship, so people were strongly united with each other. Sohyunseongnok, Chossisamdaerok series structures and patterns of a series of domestic problems occur, "mother and son, self-differentiation self undifferentiated undifferentiated ego and self-differentiation mother son, mother and self-ego undifferentiated undifferentiatedcan be subdivided into the son '.Established a symbiotic relationship between them and the U.S. established the presence of a pattern, healer, depending on the deployment method depends narrative. And is divided accordingly, self-determination and to the Son, a son, a son to be born again through repentance of the execution. Depending on the presence or absence healer than what was described on the deployment structure differs. Undifferentiated ego and self undifferentiated mother son family therapist within the family, the problem is solved. Son, a son to repent and be born again, and that caused the problem. Ego Undifferentiated mother and son self-differentiation, undifferentiated ego and self-differentiation mother son home my healer in the absence son committed suicide and executions each tragedy occurred. Personal level, but occurred at home conflicts or problems about this when analyzing the Three-generation stories of the Joseon Dynasty, by applying the theory of Bowen's Family Therapy view dimension in the relationship between family were. Toughness or desire of any one individual, but serious conflicts and problems within the family, the institution of the family itself is the root cause was. And was able to reveal aspects of narrative flow, depending on the presence or absence of family therapists vary significantly depending on his role in the rest of the family comfort and peace determines whether the Three-generation stories of the Joseon Dynasty, received an important narrative of men and axis formation. In a gauze-like situation of this problem in the Three-generation stories of the Joseon Dynasty, a personal desire or toughness in confined without the dimension of the entire family. And extrinsic psychological approach against the background of the wall in the main narrative of the sufferings of women of Korean novels, approached significance.