• 대한수학회지
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• 제42권3호
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• pp.457-470
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• 2005

Yu showed that every right (left) primitive factor ring of weakly right (left) duo rings is a division ring. It is not difficult to show that each weakly right (left) duo ring is abelian and has the classical right (left) quotient ring. In this note we first provide a left duo ring (but not weakly right duo) in spite of it being left Noetherian and local. Thus we observe conditions under which weakly one-sided duo rings may be two-sided. We prove that a weakly one-sided duo ring R is weakly duo under each of the following conditions: (1) R is semilocal with nil Jacobson radical; (2) R is locally finite. Based on the preceding case (1) we study a kind of composition length of a right or left Artinian weakly duo ring R, obtaining that i(R) is finite and $\alpha^{i(R)}R\;=\;R\alpha^{i(R)\;=\;R\alpha^{i(R)}R\;for\;all\;\alpha\;{\in}\;R$, where i(R) is the index (of nilpotency) of R. Note that one-sided Artinian rings and locally finite rings are strongly $\pi-regular$. Thus we also observe connections between strongly $\pi-regular$ weakly right duo rings and related rings, constructing available examples.

• Journal of Korean Neurosurgical Society
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• 제49권5호
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• pp.290-291
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• 2011

Persistent primitive olfactory artery (PPOA) is a rare anomaly of the anterior cerebral artery. We present one case of PPOA incidentally diagnosed with the aid of computed tomography (CT) angiography. A 24-year-old woman was admitted to our hospital after sudden onset of vertigo. Three-dimensional CT angiography revealed an anomalous artery arising from the terminal portion of the right internal carotid artery. The proximal portion of the anomalous artery coursed anteromedially and made a hairpin turn posterosuperior to the midline. PPOA may be overlooked because of its rarity, but CT angiography can be useful in detecting this rare vascular anomaly. Follow-up study is necessary in our case to confirm whether an aneurysm occurs on the PPOA.

• 대한수학회보
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• 제50권5호
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• pp.1711-1723
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• 2013

P. V$\acute{a}$mos called a ring R 2-good if every element is the sum of two units. The ring of all $n{\times}n$ matrices over an elementary divisor ring is 2-good. A (right) self-injective von Neumann regular ring is 2-good provided it has no 2-torsion. Some of the earlier results known to us about 2-good rings (although nobody so called at those times) were due to Ehrlich, Henriksen, Fisher, Snider, Rapharl and Badawi. We continue in this paper the study of 2-good rings by several authors. We give some examples of 2-good rings and their related properties. In particular, it is shown that if R is an exchange ring with Artinian primitive factors and 2 is a unit in R, then R is 2-good. We also investigate various kinds of extensions of 2-good rings, including the polynomial extension, Nagata extension and Dorroh extension.

• 대한수학회보
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• 제60권2호
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• pp.339-348
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• 2023

It is shown that every nilpotent-invariant module can be decomposed into a direct sum of a quasi-injective module and a square-free module that are relatively injective and orthogonal. This paper is also concerned with rings satisfying every cyclic right R-module is nilpotent-invariant. We prove that R ≅ R₁ × R₂, where R₁, R₂ are rings which satisfy R₁ is a semi-simple Artinian ring and R₂ is square-free as a right R₂-module and all idempotents of R₂ is central. The paper concludes with a structure theorem for cyclic nilpotent-invariant right R-modules. Such a module is shown to have isomorphic simple modules eR and fR, where e, f are orthogonal primitive idempotents such that eRf ≠ 0.

• 대한두개안면성형외과학회지
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• 제21권3호
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• pp.176-179
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• 2020

Pilomatricoma is a benign tumor arising from the primitive basal cells of the epidermis that differentiate into hair matrix cells. Mutations in the CTNNB1 gene, which encodes β-catenin (a protein involved in hair growth), play an etiological role in the development of pilomatricoma. A 34-year-old woman presenting with a mass in the right parotid region underwent an excisional biopsy. The mass was conclusively diagnosed as pilomatricoma. During pregnancy, the mass grew from 1 cm to 5 cm in diameter and was accompanied by pain and tenderness. The growth may have been facilitated by the increased production of estrogen and progesterone, which bind to receptors located in the outer root sheath cells of the hair follicles. No recurrence was observed during 6 months of follow-up.

• Journal of Chest Surgery
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• 제22권3호
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• pp.468-472
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• 1989

Bronchogenic cysts are uncommon congenital lesions which are derived from primitive foregut. Most of the bronchogenic cysts may occur at the tracheal bifurcation, both main bronchi, the lung parenchyme and the mediastinum. We experienced a case of bronchogenic cyst with a esophageal stalk. The diagnosis was made by simple chest x-ray and confirmed by bronchoscopy and chest CT. On the chest CT findings, 6.8X4.8 cm-sized oval shaped mass was located on the right posteroinferior side of the carina, elevating the right main bronchus and the thin wall of the mass was enhanced with contrast materials. On the operative findings, the esophagus and the cyst were connected with a stalk and the cyst was filled with mucinous materials. And on the histological findings, the mass was lined with pseudostratified ciliated columnar epithelium. Thus we report this case of bronchogenic cyst with review of literatures.

• 한국식생활문화학회지
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• 제3권3호
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• pp.219-243
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• 1988

The sacrificial rite has its origin in the old China's primitive folkways faith based upon animism (B.C. 25c). From the animistic faith, Confucianism made its appearance in B.C. 551. Inevitably, the procedure of Confucian sacrificial rite was developed on the basis of the preceding primitive faith. In Korean culture, the god of Chinese Confucianism introduced to Korea in A.D. 108 was mixed properly with that of Buddhism imported in A.D. 372. Traditionally, Korean primitive religion (from B.C. 10c to B.C. 2c) was the sacrificial rite practiced by 'shaman.' The 'shaman' who was able to utilize ecstasy for the good of community was gods itself, and naturally the main form of the sacrificial rite was an exorcism with a sacrificial offering (food). After Korean primitive religion had been grafted to Buddhism and Confucianism, the character of Korean culture had to become compound. The most essential conception in sacrificial rite is a discrimination of a ghost, one is the evil spirit and the other is the good spirit. According to this conception, the good spirit is a spirit which ascended to heaven, in contrast, the evil spirit is a one which did not ascend to heaven and dispersed into this world. The sacrificial rite is a method to help the evil spirit ascend to heaven or to prevent harms from it. The mode of sacrificial rite especially the dead ancestor worship was transmitted from generation to generation as a purpose of the wealth and honors of descendants. Descendants believed that the evil spirit would not harm them only after receiving sufficient food and the right sacrifice. As a result, the sacrificial rite food was the sign of filial piety and a compensation for the evil spirit. How did the Korean religious culture which was consisted of three different religions-Shamanism, Buddhism. Confucianism-be combined and transformed? The author focused the mixture and transformation of the procedure of sacrificial rite and the arrangement of sacrificial food in each religion. In this thesis, the author studied first, the conception in sacrificial rite, second, the items of sacrificial rite food according to each period. In consequence of the research, each religion had lost its uniqueness and became mixed to each other and settle down in Korean culture.

• 한국수산과학회지
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• 제53권4호
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• pp.637-649
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• 2020

An ideal 3D primitive equation model is implemented to investigate upper ocean response to typhoons, focusing on rightward bias (RWB) which means an appearance of an intensified sea surface cooling to the right side of the typhoon track. The model has 26-stratified levels and a flat bottom (1000 m), covering a rectangular domain of about 3,060 km×3,300 km with four open boundaries. The sea water is forced by an atmospheric pressure and a gradient wind of the typhoon. The model well reproduces the RWB in previous observations and theoretical analyses. For the fast moving typhoon (FMT) (-8m/sec), the model shows that in the mixed layer (ML), the RWB in the SST noticeably appears clearly illustrating the coupling between inertial motion and wind stress, but in the subsurface layer (-100m), the RWB does not emerge since a cyclonic current field (CCF) caused by wind stress curl is primarily dominant. For the slowly moving typhoon (SMT) (-3m/sec), however, the RWB does not emerge because the coupling is weakened and the CCF is rather predominant even in the ML. In the model, we conclude that the RWB noticeably emerges in the FMT but does not emerge in the SMT related to predominance of CCF.

• Journal of Chest Surgery
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• 제30권10호
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• pp.1044-1047
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• 1997

폐모세포종은 매우 드문 원발성 폐 종양으로 종괴를 구성하는 선상구조나 간엽조직 성분이 미분화된 태생기때 조직으로 구성되어 있는 종양으로 주로 성인 및 소아에서 발생한다. 본교실에서는 단순 흉부 사진에서 우측폐 하엽에 약 5Cm크기의 이상음영을 보이는 31세 남자에 발생한 폐모세포종 1례를 경험하고 이를 보고하고자한다. 수술전 임상 진단은 원발성 페종양으로 생각되었다. 수술 소견상 직경 6$\times$5$\times$4cm 크기의 단단하고 등근 종괴가 우측폐중엽에 국한되어 있었으며 부분적으로 폐상엽, 심막과 횡격막에 부착되었다. 우측 폐중됩 절제술 및 폐상엽 부분절제와 광범위한 임파절 절제를 동반하여 부분적으로 심막과 횡격막을 절제하였다. 병리조직학적으로 이상성 폐모세포종으로 진단되었다. 이상성 폐모세포종의 예후는 분화가 좋은 태아 선암종에 비해 나쁘며 외과적 절제술 이외에 특별한 치료는 없다. 폐모세포종의 임상적 경과 및 예후와 상세한 분류를 위해서는 가능한한 많은 증례를 수집할 필요가 있다고 생각된다.

• 대한수학회보
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• 제20권1호
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• pp.45-49
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• 1983

If R is ring and M is a right (or left) R-module, then M is called a faithful R-module if, for some a in R, x.a=0 for all x.mem.M then a=0. In [4], R.E. Johnson defines that M is a prime module if every non-zero submodule of M is faithful. Let us define that M is of prime type provided that M is faithful if and only if every non-zero submodule is faithful. We call a right (left) ideal I of R is of prime type if R/I is of prime type as a R-module. This is equivalent to the condition that if xRy.subeq.I then either x.mem.I ro y.mem.I (see [5:3:1]). It is easy to see that in case R is a commutative ring then a right or left ideal of a prime type is just a prime ideal. We have defined in [5], that a chain of right ideals of prime type in a ring R is a finite strictly increasing sequence I$_{0}$.contnd.I$_{1}$.contnd....contnd.I$_{n}$; the length of the chain is n. By the right dimension of a ring R, which is denoted by dim, R, we mean the supremum of the length of all chains of right ideals of prime type in R. It is an integer .geq.0 or .inf.. The left dimension of R, which is denoted by dim$_{l}$ R is similarly defined. It was shown in [5], that dim$_{r}$R=0 if and only if dim$_{l}$ R=0 if and only if R modulo the prime radical is a strongly regular ring. By "a strongly regular ring", we mean that for every a in R there is x in R such that axa=a=a$^{2}$x. It was also shown that R is a simple ring if and only if every right ideal is of prime type if and only if every left ideal is of prime type. In case, R is a (right or left) primitive ring then dim$_{r}$R=n if and only if dim$_{l}$ R=n if and only if R.iden.D$_{n+1}$ , n+1 by n+1 matrix ring on a division ring D. in this paper, we establish the following results: (1) If R is prime ring and dim$_{r}$R=n then either R is a righe Ore domain such that every non-zero right ideal of a prime type contains a non-zero minimal prime ideal or the classical ring of ritght quotients is isomorphic to m*m matrix ring over a division ring where m.leq.n+1. (b) If R is prime ring and dim$_{r}$R=n then dim$_{l}$ R=n if dim$_{l}$ R=n if dim$_{l}$ R<.inf. (c) Let R be a principal right and left ideal domain. If dim$_{r}$R=1 then R is an unique factorization domain.TEX>R=1 then R is an unique factorization domain.