Remembering and Forgetting the Korean War in the Republic of Korea

The Korean War had no official ending and has continued in a form of Cold War since 1953, the year the cease-fire agreement was signed, and yet, during the  past five decades, it appears to have faded from South Korean memory. Anti-communism became a national ideology in post-war South Korea. For a country that was endeavoring to establish a national identity that differs from communist North Korea, the establishment of an anti-communist state was inevitable. However, the collapse of the Communist Bloc and a humanitarian crisis in North Korea in the 1990s led to attitudinal changes in the South Korean public toward North Korea. The forgetting and remembering of North Korea in conjunction with the memory of the Korean War has left the South Korean people ambivalent toward North Koreans. This paper explores social encounters between North and South Koreans in the late 2000s in Seoul that illustrate the uneasy interactions that stem from past anti-communist education as well as the subsequent erasure of social memory about North Korea as part of Korean culture.   Keywords: history, memory, migration, North Korean refugee

Being Korean and being Christian: identity making in the Korean Baptist Church of Baton Rouge in the U.S. Deep South

The post-1965 generation Korean immigrants in the U.S., who have left their country for betterment of their lives, find themselves unable to acculturate to the U.S. mainstream culture. Although legally Americans, these Koreans strive to hold onto their culture they brought with them. A group of Koreans who belong to this post-1965 immigrant generation in Baton Rouge established a church to share religious and cultural experience while speaking Korean language and sharing Korean food--The Korean Baptist Church of Baton Rouge. The members of the Korean Baptist Church of Baton Rouge ( the Church ) create a familial community within Christian and Confucian ideology. Christianity guides the members\u27 spiritual lives; Confucian codes dictate their social behavior. The roles and responsibilities the members carry out resemble that of a family structure prescribed by Confucian ideology, and biblical teachings and Protestant beliefs reinforce the maintenance of the Korean church community in Baton Rouge

Nonlinear autopilot design for endo- and exo-atmospheric interceptor with thrust-vector-control

This paper proposes an autopilot design for an interceptor with Thrust-Vector-Control (TVC) that operates in the endo- and exo-atmospheric regions. The main objective of the proposed autopilot design is to ensure control performance in both atmospheric regions, without changing the control mechanism. In this paper, the characteristics of the aerodynamic forces in both atmospheric regions are first investigated to examine the issue of the conventional control mechanism at various altitudes. And then, a control mechanism, which can be applied to both atmospheric regions, is determined based on the analysis results. An autopilot design is then followed by utilizing the control mechanism and the feedback linearization control (FBLC) method. Accordingly, the proposed autopilot does not rely on changing the control mechanism depending on flight condition unlike the conventional approach as well as it can adjust the control gains automatically according to the changes of flight operating conditions. In this paper, the robustness of the proposed autopilot is investigated through the tracking error analysis and the relative stability analysis in the presence of model uncertainties. The physical meaning of the proposed autopilot is also presented by comparing to the well-known three-loop control structure. Finally, numerical simulations are performed to show the performance of the proposed method

Extended study of matter-wave diffraction from a periodic array of half-planes: Influences of van der Waals interactions on half-plane reflection/diffraction

Department of ChemistryHalf-plane reflection/diffraction refer to overall optical phenomena occurring at a periodic array of half-planes, playing a significant role in various fields of science and technology such as statistical quantum mechanics and ultrahigh frequency communication in urban areas. In Kirchhoff approximation, these phenomena are understood as multiple scatterings over half-planes. In atom optics, such reflection mechanism was utilized to increase reflectivity of atoms from solid materials and named as ???Fresnel diffraction mirror???.We recently have shown that matter-wave optical phenomena from square-wave gratings are governed by edge diffraction from an array of half-planes with decreasing strip widths of square-wave gratings while quantum reflection becomes predominant as the strip widths increase. Within this thesis, we extend our previous work to study how the interaction between matter-waves and top surfaces of strips affects half-plane reflection/diffraction. Interactions between particles and surfaces, namely, van der Waals interactions, influence matter-wave diffraction from square-wave gratings in two different manners - a manifestation of quantum reflection and a reduction of reflection/ diffraction efficiencies. To effectively study the latter case, i.e., an attenuation effect, we adapt a theoretical study obtained by Kouznetsov and Oberst. By comparing our measurement to the theoretical results, we find that the effects of van der Waals interactions appear differently for different particles, different grating periods and different de Broglie wavelengths. However, the adapted theoretical analysis is still not available to provide quantitative analysis for the attenuation effect. Hence, we suggest that the current theory should be improved by considering multiple scatterings of phase shifted waves induced by the van der Waals potentials in Fresnel integral. Furthermore, we look into the applicability of half-plane reflection/diffraction to van der Waals clusters and bigger molecules. Half-plane reflection of He3 was demonstrated in our previous paper with a square wave grating, and yet it remains to be challenging to study half-plane diffraction for the van der Waals clusters due to the low diffraction efficiencies. As a breakthrough, we suggest a new type of grating which is referred to as ???meta grating??? by embedding a large period into a periodic array of half-planes. Such a combination of two different grating periods is expected to enable enhanced diffraction efficiencies of fragile van der Waals clusters. Besides, a theoretical study is carried out with the consideration of attenuation effects for nitrogen and helium trimer to test the possibility of applying half-plane reflection/diffraction to bigger molecules. Considering that the reflectivity goes up with decreasing grating periods, square-wave gratings of 20 m period with 1 and 0.1 m strip widths are used in our calculation. Compared to quantum reflection, much higher reflectivity is observed and it shows the possibility to study matter-wave optical phenomena of particles with high polarizability.ope

An Empirical Examination of Consumer Behavior for Search and Experience Goods in Sentiment Analysis

With the explosive increase of user-generated content such as product reviews and social media, sentiment analysis has emerged as an area of interest. Sentiment analysis is a useful method to analyze product reviews, and product feature extraction is an important task in sentiment analysis, during which one identifies features of products from reviews. Product features are categorized by product type, such as search goods or experience goods, and their characteristics are totally different. Thus, we examine whether the classification performance differs by product type. The findings show that the optimal threshold varies by product type, and simply decreasing the threshold to cover many features does not guarantee improvement of the classification performance

Suppression of Dielectric Loss at High Temperature in (Bi1/2Na1/2)TiO3 Ceramic by Controlling A-site Cation Deficiency and Heat Treatment

Dielectric capacitors are integral components in electronic devices that protect the electric circuit by providing modulated steady voltage. Explosive growth of the electric automobile market has resulted in an increasing demand for dielectric capacitors that can operate at temperatures as high as 400oC. To surpass the operation temperature limit of currently available commercial capacitors that operate in temperatures up to 125oC, Bi1/2Na1/2TiO3 (BNT), which has a large temperature-insensitive dielectric response with a maximum dielectric permittivity temperature of 300oC, was selected. By introducing an intentional A-site cation deficiency and post-heat treatment, we successfully manage to control the dielectric properties of BNT to use it for high-temperature applications. The key feature of this new BNT is remarkable reduction in dielectric loss (0.36 to 0.018) at high temperature (300oC). Structural, dielectric, and electrical properties of this newly developed BNT were systematically investigated to understand the underlying mechanism

Fabrication of flexible UV nanoimprint mold with fluorinated polymer-coated PET film

UV curing nanoimprint lithography is one of the most promising techniques for the fabrication of micro- to nano-sized patterns on various substrates with high throughput and a low production cost. The UV nanoimprint process requires a transparent template with micro- to nano-sized surface protrusions, having a low surface energy and good flexibility. Therefore, the development of low-cost, transparent, and flexible templates is essential. In this study, a flexible polyethylene terephthalate (PET) film coated with a fluorinated polymer material was used as an imprinting mold. Micro- and nano-sized surface protrusion patterns were formed on the fluorinated polymer layer by the hot embossing process from a Si master template. Then, the replicated pattern of the fluorinated polymer, coated on the flexible PET film, was used as a template for the UV nanoimprint process without any anti-stiction coating process. In this way, the micro- to nano-sized patterns of the original master Si template were replicated on various substrates, including a flat Si substrate and curved acryl substrate, with high fidelity using UV nanoimprint lithography