• 대한수학회지
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• 제52권4호
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• pp.853-868
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• 2015

Let G be a complex semisimple simply connected linear algebraic group. The main result of this note is to give several equivalent criteria for the untwistedness of the twisted cubes introduced by Grossberg and Karshon. In certain cases arising from representation theory, Grossberg and Karshon obtained a Demazure-type character formula for irreducible G-representations as a sum over lattice points (counted with sign according to a density function) of these twisted cubes. A twisted cube is untwisted when it is a "true" (i.e., closed, convex) polytope; in this case, Grossberg and Karshon's character formula becomes a purely positive formula with no multiplicities, i.e., each lattice point appears precisely once in the formula, with coefficient +1. One of our equivalent conditions for untwistedness is that a certain divisor on the special fiber of a toric degeneration of a Bott-Samelson variety, as constructed by Pasquier, is basepoint-free. We also show that the strict positivity of some of the defining constants for the twisted cube, together with convexity (of its support), is enough to guarantee untwistedness. Finally, in the special case when the twisted cube arises from the representation-theoretic data of $\lambda$ an integral weight and $\underline{w}$ a choice of word decomposition of a Weyl group element, we give two simple necessary conditions for untwistedness which is stated in terms of $\lambda$ and $\underline{w}$.

• 한국산학기술학회논문지
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• 제8권6호
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• pp.1648-1654
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• 2007

본 연구의 목적은 최근 전 세계적으로 확산되고 있는 리얼리티 쇼 프로그램의 사회 문화적 특성에 따른 현상을 살펴보고, 케이블 TV 프로그램 <스캔들>의 분석을 통해서 나타나는 여러 특성 등을 검토하고자 하는 것이다. TV리얼리티 쇼 프로그램 <스캔들>에 나타나고 있는 제작 방식은 다양한 장르의 특성이 결합된 새로운 시도로 분석된다. 그러나 그 저변 확대에도 불구하고 리얼리티 쇼 프로그램이 방송의 공영적인 책무를 무시한 선정적이고 관음적인 호기심을 자극하는 오락의 대상으로만 부각되고 있는 현 상황은 텔레비전의 저급문화가 확산되는 심각성을 간과할 수 없게 하는 문제점을 발생시키고 있다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제14권2호
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• pp.73-83
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• 2014

Many recent theoretical developments in the field of machine learning and control have rapidly expanded its relevance to a wide variety of applications. In particular, a variety of portfolio optimization problems have recently been considered as a promising application domain for machine learning and control methods. In highly uncertain and stochastic environments, portfolio optimization can be formulated as optimal decision-making problems, and for these types of problems, approaches based on probabilistic machine learning and control methods are particularly pertinent. In this paper, we consider probabilistic machine learning and control based solutions to a couple of portfolio optimization problems. Simulation results show that these solutions work well when applied to real financial market data.

• 영어어문교육
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• 제17권2호
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• pp.79-91
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• 2011

The purpose of this paper was to take an in-depth look at early American English around the $17^{th}$ and $18^{th}$ century when immigrants from different European countries started to move into the New World. The paper attempted to describe early American English in relation to the process of immigration and settlement from a historical perspective. With a focus on major features of early American English such as uniformity, archaism and richness of lexicon, the paper tried to answer the questions such as how settlement influenced the formation and distribution of regional dialects across the continent, why immigrants tended to show a preference for a uniform way of speaking rather than choosing a variety of regional dialects for communication, and what role foreign languages played in the development of early American English. The overall findings based on the answers to these questions showed how American English went through a variety of processes and changes at the early stages of its development to become a national language later. The paper concluded with some remarks about the implications of the findings for EFL learning and the direction of future research on early American English.

• 대한수학회지
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• 제44권1호
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• pp.35-54
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• 2007

Let $M_c$ = M(2, 0, c) be the moduli space of O(l)-semistable rank 2 torsion-free sheaves with Chern classes $c_1=0\;and\;c_2=c$ on a K3 surface X, where O(1) is a generic ample line bundle on X. When $c=2n\geq4$ is even, $M_c$ is a singular projective variety equipped with a holomorphic symplectic structure on the smooth locus. In particular, $M_c$ has trivial canonical divisor. In [22], O'Grady asks if there is any symplectic desingularization of $M_{2n}$ for $n\geq3$. In this paper, we show that there is no crepant resolution of $M_{2n}$ for $n\geq3$. This obviously implies that there is no symplectic desingularization.

• 한국멀티미디어학회논문지
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• 제18권11호
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• pp.1383-1390
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• 2015

By according to the development of the mobile devices, a touch screen provides the variety of inputting character and the flexibility of user interface. Currently, the physically simple touch method is widely used for English input but this simple touch is not increasing the variety of inputs and flexibility of the user interfaces. In this paper, we propose a new method to input English characters continuously by recognizing gestures instead of the simple touches. The proposed method places the rotational pickers on the screen for changing the alphabetical sequence instead of the keys and inputs English characters through the flick gestures and the touches. Simulation results show that the proposed keypad method has better performance than the keypad of the conventional methods.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.519-523
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• 2007

Gas(or methane) hydrates are solid solutions when water molecules are linked through hydrogen bonding and create host lattice cavities that can enclose a large variety of guest gas molecules. The natural gas hydrate crystal may exist at low temperature above the normal freezing point of water and high pressure greater than about 30 bars. A lot of quantities of natural gas hydrates exists in the earth and many production schemes are being studied. In the present investigation, depressurization method was considered to predict the production of gas and the simulation of the two phase flow - gas and water - in porous media is being carried out. The simulation show about the fluid flow in porous media have a variety of applications in industry. Results provide the appearance of gas and water production, the pressure profile, the saturation of gas/ water/ hydrates profiles and the location of the pressure front.

• The Korean Journal of Pain
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• 제19권1호
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• pp.123-126
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• 2006

Spinal cord stimulation (SCS) has been used since 1967 for refractory chronic pain. SCS has recently undergone a variety of technical modifications and advances, and it has been applied in a variety of pain conditions. SCS has been most commonly applied for those patients with chronic back and leg pain and failed back surgery syndrome (FBSS). The clinical hallmark of FBSS is chronic postoperative pain. The pain pattern varies and the pain may show an axial or radicular distribution. Chronic intractable pain after FBSS is difficult to treat. This report describes our experience with treating chronic pain in two patients who suffered from FBSS with a spinal cord stimulator. A permanent spinal cord stimulator was implanted after a successful trial of stimulation with temporarily implanted electrodes. After 5 months of follow-up, the two patients had satisfactory improvement of their pain.

• Current Research on Agriculture and Life Sciences
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• 제33권1호
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• pp.7-14
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• 2015

This study identifies the complementarity or substitutability among apple production technology bundles. To identify the production technology bundle relationships, this paper focuses on the 8 most commonly used technology groups, including a high density plant, normal density plant, M9, M26, more than 70% adoption ratio of a medium-maturing variety, the adoption of a new variety, artificial pollination, and low-temperature storage. The results show that M9 has a complementary relationship with a high density plant, yet a substitute relationship with a normal density plant. Meanwhile, M26 has a complementary relationship with both a high and normal density plant. No substitute relationship is found between M9 and M26, yet a complementary relationship is identified between the adoption of artificial pollination and low-temperature storage and M9 or M26.

• The International Journal of Costume Culture
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• 제4권3호
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• pp.203-216
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• 2001

Subjects were 405 female college students and 505 was utilized for structural equation modeling. As results, hedonic shopping value had positive effects on impulse purohasing, variety seeking, and purchasing involvement. In contrast, interestingly, impulse purchasing did not show any significant effect on brand loyalty and purchasing involvement had rather a positive effect on brand loyalty. There was a Positive effect of hedonic shopping value on brand loyalty. This result indicates that people who get more involved in and enjoy clothing shopping are likely more brand loyal than others. This seems to come from the intrinsic characteristics of shopping. People who enjoy clothing shopping likely have high level of fashion or style concern, and this might lead higher levels of purchasing involvement and brand loyalty. Due to the symbolic characteristics of clothing, the brand loyalty of clothing seems to be more symbolic and emotive rather than utilitarian and cognitive.