• Journal of the Chungcheong Mathematical Society
• /
• v.20 no.4
• /
• pp.569-575
• /
• 2007

Let M be a nonzero module. M has the property that every submodule of M lies over a direct summand of M. We study some properties of such a module. The endomorphism ring of such a module is also studied. The relationships of such a module to the semi-regular modules, and to the semi-perfect modules are described.

• Journal of the Korean Mathematical Society
• /
• v.42 no.2
• /
• pp.203-222
• /
• 2005

Thompson series is a Hauptmodul for a genus zero group which lies between $\Gamma$o(N) and its normalizer in PSL2(R) ([1]). We construct explicit ring class fields over an imaginary quadratic field K from the Thompson series $T_g$($\alpha$) (Theorem 4), which would be an extension of [3], Theorem 3.7.5 (2) by using the Shimura theory and the standard results of complex multiplication. Also we construct various class fields over K, over a CM-field K (${\zeta}N + {\zeta}_N^{-1}$), and over a field K (${\zeta}N$). Furthermore, we find an explicit formula for the conjugates of Tg ($\alpha$) to calculate its minimal polynomial where $\alpha$ (${\in}{\eta}$) is the quotient of a basis of an integral ideal in K.

• Philosophy of Education
• /
• no.46
• /
• pp.45-70
• /
• 2012

The purpose of this study is researching on educational difficulty in the history of western education. In other words, the goal and significance of this paper lies in knowing the essential meaning of education based on the norms of difficulty. The major method for this study is hermeneutical-anthropological pedagogy. My fundamental claim is the following: the essential nature of teaching is difficulty at any instructional condition and situations. Such a discrete idea was clearly identified and confirmed in the process of pedagogical anthropology. That is, through the consciousness of educational difficulty and critical review for the history of western education, I can cleary define the concept of educational difficulty. Educational difficulty was various ways for understanding by all audiences. Namely, various formulars were developed for understanding it according to the age, cultures, nations, ideology, etc.. But there are continuous characters on the way for understanding on educational difficulty. The results on research are as followings. In the primitive age, fundamental difficulty of education lies in the initiation ceremony. At the classical ancient time, the purpose of education was 'Politai' with politike arete, in this educational conditions, instruction have a complex dimension politically as well as psychologically. At the medieval age, educational difficulty lies in the 'Askese' for instructional methods. In the modern and conventional age, educational difficulty is more and more complex and confused on goals, methods, evaluations, etc.. Most of all, the major or key concept of educational difficulty in this world is the conflict between the two instructional principles, that is, objectivism and constructivism in education. At now, the schoolworks for instruction over all educational situations and conditions have a difficulty of traditional as well conventional dilemma. In conclusion, educational difficulty have formal, natural, original attribute and it is general and universal phenomenon.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1996.04a
• /
• pp.143-145
• /
• 1996

A new method of fabricating 3-dimensional patterns on single crystal silicon is presented in this paper. The method utlizes both chemical and mechanical reactions to make patterns with dimensions of few microns in width and submicron in height. The primaryadvantage ofthis new method over conventional methods of making patterns on silicon lies in its cost effectiveness and speed. The process introduced in this paper is a maskless process and does not reauire expensive capital investment. It is expected that this method can be employed for flexible and cost effective fabrication of micro-machine components in MEMS application.

• Communications of the Korean Mathematical Society
• /
• v.39 no.2
• /
• pp.303-311
• /
• 2024

In this paper, our focus lies in exploring the concept of Cohen-Macaulay dimension within the category of homologically finite complexes. We prove that over a local ring (R, 𝔪), any homologically finite complex X with a finite Cohen-Macaulay dimension possesses a finite CM-resolution. This means that there exists a bounded complex G of finitely generated R-modules, such that G is isomorphic to X and each nonzero G_i within the complex G has zero Cohen-Macaulay dimension.

• Journal of Popular Narrative
• /
• v.27 no.2
• /
• pp.215-262
• /
• 2021

This thesis focuses on Wandeuki and Elegant Lies - novels written by Kim Ryeo-reong and adapted into the film by Director Lee Han; this thesis analyzes the process of storytelling being transformed as the media is converted. Also, this thesis discusses cultural-political implications of transmedia storytelling where different narrative responses coexist concerning post-IMF family disorganization and "individualization." First of all, this thesis critically reviews existing discourses on the concept of transmedia storytelling and refers to 'transfictionality' the narratological concept of Marie-Laure Ryan in order to look into media conversion storytelling that starts from original novels. The novels Wandeuki and Elegant Lies show two aspects of "individualization" that adopts existential conditions of family disorganization. Wandeuki deviates from patriarchal family romance through self-discovery and exhibits loose family bond, which is something similar to companionship of close individuals. Elegant Lies shows individualization of pain by portraying a teenager who found herself completely isolated, while showing that it is impossible for the people left behind to mourn. On the other hand, director Lee Han's films and show stories in which family members, who are confronting family dissolution, rediscover and restore their families against family dissolution. The film promotes the expansion of family community through multicultural identity, and the film completes condolence of the people left behind by having the remaining families survive as survivors of suicide. The storyworld of the novels puts emphasis on 'self-discovery' of individual adolescents, while the storyworld of the movies puts emphasis on 'rediscovery of family'. Through transformation of storytelling - especially the redesigning of narrative structures called "modification" - transmedia storytelling shows that the relationship between media-converted texts is far from "faithful representation," but rather, shows conflicting themes and perspectives. With a reference point of 'the emergence of character' transmedia storytelling, which is predicated on the original work but aims to free itself from the original work by transforming storytelling through media conversion, opens up polyphonic storyworld by creating heterogeneous voices. In the post IMF-era, where uncertainty mounts over family dissolution and individualization, polyphonic storyworld created by transmedia storytelling provides an opportunity to experience disparate desires over individual freedom/risk and complacency toward community. We can call this the cultural-political implication of transmedia storytelling based on transferring, transcednding, and transforming.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.13 no.4
• /
• pp.11-28
• /
• 2005

The research purpose of A Study on the Effect of Aviation Safety over the Air Passenger's Behavior for enhancement of aviation safety management lies at the judgement that passenger's airlines choice criteria has much changed after several serious aviation accidents as before when we used to overlook "aviation safety" variable through surveying to Korean aviation passengers and foreigners visit or travel Korea on various purposes. This study will be regarded significant in terms that empirical analysis was used to prove "Aviation Safety", a variable which had not been regarded as a airline choice factor within Korea air transport market so far, and has an effect on the air passengers' airline preference change and choice after recent frequent aviation accidents. I wish, it can be another opportunity for Korean two national flag airlines to reappraise and reinforce the significance of "aviation safety" and set forth immediate vigorous efforts to support the government's aviation safety improvement countermeasures.

• Bulletin of the Korean Mathematical Society
• /
• v.51 no.3
• /
• pp.813-822
• /
• 2014

A ring R is called quasipolar if for every a 2 R there exists $p^2=p{\in}R$ such that $p{\in}comm^2{_R}(a)$, $ a+p{\in}U(R)$ and $ap{\in}R^{qnil}$. The class of quasipolar rings lies properly between the class of strongly ${\pi}$-regular rings and the class of strongly clean rings. In this paper, we determine when a $2{\times}2$ matrix over a local ring is quasipolar. Necessary and sufficient conditions for a $2{\times}2$ matrix ring to be quasipolar are obtained.

• Journal of the Korean Chemical Society
• /
• v.25 no.3
• /
• pp.166-171
• /
• 1981

The reactions of trimethylbenzenes were investigated over dealuminated, cation-exchanged mordenite catalysts. Higher reaction temperature favored the formation of disproportionation products. In the reaction of 1,2,4-trimethylbenzene, the formation of 1,3,5-trimethylbenzene and the disproportionation products decreased sharply with reaction time. The product distribution, especially the distribution of trimethylbenzenes, suggests that the effective pore diameter of Ba-exchanged dealuminated mordenite catalysts lies somewhere between 8.1 and 8.6${\AA}$.

• Nuclear Engineering and Technology
• /
• v.32 no.1
• /
• pp.17-33
• /
• 2000

A mechanistic model based on wall-attached bubble coalescence, previously developed by the authors, was extended to predict a vow high critical heat flux (CHF）in highly subcooled flow boiling, especially for high mass flux and small tube diameter conditions. In order to take into account the enhanced condensation due to high subcooling and high mass velocity in small diameter tubes, a mechanistic approach was adopted to evaluate the non-equilibrium flow quality and void fraction in the subcooled water flow boiling, with preserving the structure of the previous CHF model. Comparison of the model predictions against highly subcooled water CHF data showed relatively good agreement over a wide range of parameters. The significance of the proposed CHF model lies in its generality in applying over the entire subcooled flow boiling regime including the operating conditions of fission and fusion reactors.