• Kyungpook Mathematical Journal
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• v.53 no.4
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• pp.497-505
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• 2013

The noncommutative Singer-Wermer conjecture states that every derivation on a Banach algebra (possibly noncommutative) leaves primitive ideals of the algebra invariant. This conjecture is still an open question for more than thirty years. In this note, we approach this question via some sufficient conditions for the separating ideal of ${\phi}$-derivations to be nilpotent. Moreover, we show that the spectral boundedness of ${\phi}$-derivations implies that they leave each primitive ideal of Banach algebras invariant.

• Korean Journal of Human Ecology
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• v.8 no.2
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• pp.327-337
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• 1999

Primitive men's primordial formative activity derives from incarnation contained in intensive vitality and strong creativity mind. The trend of modern fashion requiring the boundless imagination can be called that it, just, itself, has something in common with basic spiritual activity that primitive men had. What is concerning how modern fashion designers have developed formative language through enchanting primitive art is as follows. 1. The nature's mysterious power appears to be transformed into personified image. The incarnation for acquiring beauty, power, prestige of genius appears in the form of personification, making use of mask in modern fashion. 2. As for primitive men, the whole universe has a potentiality as a symbol. The symbolism of primitive art based on religion and myth appears in modern art as the form of presenting oppositional objects together in one space. 3. Primitive art is the purest form and the most unpolluted. This shows the natural quality being assimilated into nature, which is expressed in modern fashion as intensity, free-spirit, simplicity, etc. 4. The primitive men's anxiety to the outside world appears as impulse. The geometrical form of primitive art occurred in the shape of impulse appears in expressional form of modern fashion. 5. The real existence in primitive art inducing real materials and objects, in themselves, into formative world appears in modern art in the way of expression such as repetition, enlargement, exact reproduction.

• Journal of architectural history
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• v.14 no.1 s.41
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• pp.135-150
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• 2005

Historical study of Korean traditional houses have been carried, mainly, based on the geographical region of Korean peninsula. However, the case of primitive houses can not be researched according to the geographical and racial concept of modern nations. This study aims to examine the primitive houses of ethnic minorities of northeastern China, where the cultural and racial background have been deeply rooted in the history of Korea as well as Korean traditional houses. Through the field research and literary materials, the basic types of primitive houses of the five ethnic minorities could be identified. Among these types, those that have possible relationship with Korean houses, are cone shaped house, underground house, and elevated wooden house. Archeological evidences of underground houses were amply found in Korea already, but above ground evidences could not be found. However, It seems quite certain that the cone shaped houses and elevated wooden houses, too, existed in Korea as one of the earliest housing types, as can be examined in remaining examples in Korean peninsula. With no doubt, the primitive houses of Korea have strong connection with that of the ethnic minorities of northeastern China. This can be verified through the facts that the evidences of cone shaped houses, the similarities of the use of Inner space, the evidences of elevated wooden houses. Also, the combination of wooden floor and ondol, which is known to be one of the strongest characteristic of Korean traditional houses, could be originated from the combination of primitive summer house, the elevated wooden house, and the winter house, the underground house with ondol.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.489-496
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• 2007

Let g be a continuous function on an interval I which is not constant on any subinterval of I, and let ${\mu}$ be a Borel measure on I. In this paper we give a necessary and sufficient conditions guaranteeing, for the strongly measurable function f on I with values in a Banach space X, the existence of a continuous primitive function F on I with respect to g.

• Journal of The Korean Astronomical Society
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• v.40 no.4
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• pp.107-111
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• 2007

The original environment of the solar system can be inferred by studying the oxygen isotope ratios in the Sun as well as in primitive meteorites and comets. The oxygen isotopic fractionation measured in primitive meteorites is mass-independent, which can be explained by the isotopic-selective photodissociation of CO. The isotopic-selective photodissociation model in a collapsing cloud by Lee et al. (2007) imply the birth of the Sun in a stellar cluster with an enhanced radiation field, which is consistent with the inferred presence of $^{60}Fe$.

• Korean Journal of Crystallography
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• v.14 no.1
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• pp.13-15
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• 2003

For all primitive centric space groups in the triclinic, monoclinic and orthorhombic systems, either phase 0 or π can be allocated to three different kinds of reflections in order to specify the origin at one of the eight centers of symmetry. and the same holds for all primitive acentric space groups belonging to the point group 222. If these phased reflections are used as a basic set, more and more phased reflections with better accuracy could emerge in the process of direct methods.

• Proceedings of the KIEE Conference
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• 1987.07b
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• pp.1100-1103
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• 1987

In this paper, we report a method for the primitive segments extraction from printed Korean characters without thinning as a preliminary stage to design an efficient recognition system. The primitive segments are defined by fundamental subpatterns which are vertical(I), right sloping(/), left. sloping(\). horizontal(-), and circular segment(o). The circular segment among the five kinds of segment is different from the others in geometrical properties. Therefore, at first, the circular segment is extracted by using the closed circle of the inner boundary and the geometrical characteristics of its outer. Next, linear segments are separated from the character pattern by means of a directional coding method. Finally, primitive segments are extracted from each set of linear segments by using a projection profile which involves the fact whether the segment has branches or not. The experimental results show that this method reduces computation time and storage space in comparision with the existing methods.

• Journal of the Korean Mathematical Society
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• v.34 no.4
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• pp.809-824
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• 1997

With the primitive orders in quaternion algebra, theta series associated with these orders are constructed. Here, we studied the space of modular forms generated by these theta series.

• Journal of Information Processing Systems
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• v.8 no.3
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• pp.409-420
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• 2012

The decision-making by agents in games is commonly based on reinforcement learning. To improve the quality of agents, it is necessary to solve the problems of the time and state space that are required for learning. Such problems can be solved by Macro-Actions, which are defined and executed by a sequence of primitive actions. In this line of research, the learning time is reduced by cutting down the number of policy decisions by agents. Macro-Actions were originally defined as combinations of the same primitive actions. Based on studies that showed the generation of Macro-Actions by learning, Macro-Actions are now thought to consist of diverse kinds of primitive actions. However an enormous amount of learning time and state space are required to generate Macro-Actions. To resolve these issues, we can apply insights from studies on the learning of tasks through Programming by Demonstration (PbD) to generate Macro-Actions that reduce the learning time and state space. In this paper, we propose a method to define and execute Macro-Actions. Macro-Actions are learned from a human subject via PbD and a policy is learned by reinforcement learning. In an experiment, the proposed method was applied to a car simulation to verify the scalability of the proposed method. Data was collected from the driving control of a human subject, and then the Macro-Actions that are required for running a car were generated. Furthermore, the policy that is necessary for driving on a track was learned. The acquisition of Macro-Actions by PbD reduced the driving time by about 16% compared to the case in which Macro-Actions were directly defined by a human subject. In addition, the learning time was also reduced by a faster convergence of the optimum policies.

• Journal of architectural history
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• v.17 no.2
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• pp.67-81
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• 2008

Aldo Rossi explained Roman Forum as a significant urban artifact, because Roman Forum analogically showed not only an image of Roman Empire but also a figure of primitive design for its region. Thus the comparison and analysis between characteristics of Aldo Rossi's architectural works which are based on the theory of 'Analogical city' and the forums, the urban artifacts, was proceeded in this study. Consequently, it was discovered that Aldo Rossi had used his analogical thinking from the forum for his architectural languages such as gable roofs, square windows with depth, columns and so on. His analogical use of organizing spaces, such as courtyard type and pillar corridor type, has also shown that their types came from forum spaces. His analogical aspects of the forum: a space where urban images are analogically formed; were expressed in the 'Theater of Science' with the urban architecture form as the actor and the Theatre as the stage for analogical urban performances. Nevertheless, the expression of primitive design which divides the Roman Forum from other forums was actualized in 'the Theater of the World'. He not only analogically used types from Roman Forum in architectural design but also used boat in Water space, which decided the lifestyle and culture of Venice even before the civilization, to express the primitive design of Venice. Consequently, Aldo Rossi, by aiming the severance from the tradition, provided the possibility of explaining the newest modem type within the historical meaning by forming type which finds its continuance in history through 'the Theater of the World' and through analogical thinking along with the level of modern culture, to our urban architectural atmosphere that has lost its historical meanings.