• Journal of the Korean Mathematical Society
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• v.41 no.6
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• pp.1035-1047
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• 2004

In this paper, we study the unit tangent sphere bundles T$_1$M(4c) of complex space forms M(4c) with constant holomorphic sectional curvature 4c. In particular, we determine T$_1$M(4c) whose Ricci tensors satisfy the Einstein-like conditions.

• Korean Circulation Journal
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• v.48 no.12
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• pp.1081-1096
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• 2018

We reviewed the anatomical characteristics of the conduction system in the ventricles of human and ungulate hearts and then raised some questions to be answered by clinical and anatomical studies in the future. The ventricular conduction system is a 3-dimensional structure as compared to the 2-dimensional character of the atrial conduction system. The proximal part consisting of the atrioventricular node, the bundle of His and fascicles are groups of conducting cells surrounded by fibrous connective tissue so as to insulate from the underlying myocardium. Their location and morphological characters are well established. The bundle of His is a cord like structure but the left and right fascicles are broad at the proximal and branching at the distal part. The more distal part of fascicles and Purkinje system are linear networks of conducting cells at the immediate subendocardium but the intra-mural network is detected at the inner half of the ventricular wall. The papillary muscle also harbors Purkinje system not in the deeper part. It is hard to recognize histologically in human hearts but conducting cells as well as Purkinje cells are easily recognized in ungulate hearts. Further observation on human and ungulate hearts with myocardial infarct, we could find preserved Purkinje system at the subendocardium in contrast to the damaged system at the deeper myocardium. Further studies are necessary on the anatomical characteristics of this peripheral conduction system so as to correlate the clinical data on hearts with ventricular arrhythmias.

• Journal of Chest Surgery
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• v.22 no.1
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• pp.116-122
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• 1989

During 22-year period ending in June 1988, operation was performed on 22 patients with primary heart tumor at Yonsei University College of Medicine. Mean age was 38.8*3.03[mean \ulcornerEM] ranging from 14 to 63 years old. Twenty cases were myxomas. Others were fibromyxoma and rhabdomyosarcoma. All patients complained of dyspnea on exertion. Nine cases had palpitation. Other constitutional symptoms were weight loss [7 cases], headache [4 cases], generalized edema [3 cases] and cough [3 cases]. Five cases had neurological symptoms and signs preoperatively. Preoperative NYHA Class was poor [Class II; 8 cases, III; 9 cases and IV; 5 cases]. The most common site of tumor origin was fossa ovalis limbus [16 cases; 72.8%]. Because of severe mitral regurgitation and of recurrent myxoma, 2 cases were reoperated for mitral valve replacement. Postoperative complications were postoperative mitral regurgitation [5 cases; 22.8%] and arrhythmia [4 cases; 18.2%], one of which was supra-His bundle block. All patient survived operation. Follow-up of 15 patients [mean 28.95*8.3 months] was good as functional class 1[8 cases] or II [7 cases]. More effective adjuvant therapy will be necessary to improve long-term prognosis for malignant primary heart tumor.

• Journal of Fashion Business
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• v.6 no.3
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• pp.1-14
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• 2002

According to Scythian tradition, many burials contained numerous artifacts, from weapons and harness to everyday objects and a multiplicity of personal adornments. Most valuable of all is the Scythian Gold often lavishly decorated with precious stones. The detailed images on these pieces make it possible for us to picture the appearance of the Scythians, their clothes and weapons. Scythian Gold Plaques were attached to the fabric in such a way that when they moved with each movement of the wearer it created what must have been a dazzling sight in bright daylight. Scythian Gold Plaques were divided into several types according to the shape, animal style(curved beast shape, profile shape, head reversed over its back shape), round shape, quadrilateral form, star shape, flower shape, crescent shape, bundle shape, human appearance. Through the antique tombs bequests of Three Kingdom States hereby describe the original forms of their source of Baekje gold plaque were influenced by Scythe style. Like nearly all Scythian ornaments, such gold pieces were designed to maximize various magical powers and to signify the owner's importance relative to his fellow tribesmen.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.150-155
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• 1997

Modelling and Simulation of the activation process for the myocardium is meaningful to understand special excitation conduction system in the heart and to study cardiac functions. In this paper, we propose two dimensional cellular automata model for the activation process of the myocardium and simulated by means of discrete time and discrete event algorithm. In the model, cells are classified into anatomically similar characteristic parts of heart; SA node, internodal tracks, AV node, His bundle, bundle branch and four layers of the ventricular muscle, each of which has a set of cells with preassigned properties, that is, activation time, refractory duration and conduction time between neighbor cell. Each cell in this model has state variables to represent the state of the cell and has some simple state transition rules to change values of state variables executed by state transition function. Simulation results are as follows. First, simulation of the normal and abnormal activation process for the myocardium has been done with discrete time and discrete event formalism. Next, we show that the simulation results of discrete time and discrete event cell space model is the same. Finally, we compare the simulation time of discrete event myocardium model with discrete time myocardium models and show that the discrete event myocardium model spends much less simulation time than discrete time myocardium model and conclude the discrete event simulation method Is excellent in the simulation time aspect if the interval deviation of event time is large.

• Sijohaknonchong
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• v.24
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• pp.139-171
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• 2006

'Geumokchongbu' that is Gajib(a book of songs) is composed only the works of An Minyoung. Ahn Minyoung was not only an editor of Gajib and also Musician that is a kind of singer, Because of his works, he is the one who should be studied for the history of literature of Sijo in the latter period of Chosun, especially in 19th century. Through the studies on 'Geumokchongbu' that is the Gajib edited by Ahn Minyoung. his excellent musical talent could be confirmed. 'Geumokchongbu' which is another Gajib in compared to 'Gagokwonryu' was produced under his careful musical consideration. The tunes shown on Gajib reflected the situation of Gagok just as it was sung and played in that period. Generally, the system of Gajib which was edited in that period Including 'Geumokchongbu' was continued on nowaday's tradition of singing and playing the Gagok. Nevertheless lots of studied results about Ahn Minyoung, the editor of Gajib. was reported. his personal aspect still was not explained for many detailed part. The introduction o( the background of works and various explanation was recorded for each work in 'Geumokchongbu'. The written year of works was found in the introductions. and some of Ahn Minyoung's life could be traced through the chronicle. It could be confirmed for his broad knowledge about music and detailed reality of active correspondences with many loyal family including Daewongun, Lee Haeung and artists in that period. The existence of a type of singing and playing which takes any part of specific tunes shown on Gajib was confirmed. For example, Hachuksi, a blessing poem, dedicated for Daewongun or loyal family was created for supposing singing and playing thoroughly. Accordingly, Hachuksi dedicated to specific persons might be sung and played at the same place, and in the same bundle. Through the study, the way of singing and playing the Gagok was much various, and the variety was confirmed concretely.

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.44-51
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• 1994

It is known that the normal His-Purkinje system provides for nearly synchronous activation of right (RV) and left (LV) ventricles. When His-Purkinje conduction is abnormal, the resulting sequence of ventricular contraction must be correspondingly abnormal. These abnormal mechanical consequences were difficult to demonstrate because of the complexity and the rapidity of it's events. To determine the relationship of the phase changes and the abnormalities of ventricular conduction, we performed phase image analysis of $^{99m}Tc$-RBC gated blood pool scintigrams in patients with intraventricular conduction disturbances (24 complete left bundle branch block (C-LBBB), 15 complete right bundle branch block (C-RBBB), 13 Wolff-Parkinson-White syndrome (WPW), 10 controls). The results were as follows; 1) The ejection fraction (EF), peak ejection rate (PER), and peak filling rate (PFR) of LV in gated blood pool scintigraphy (GBPS) were significantly lower in patients with C-LBBB than in controls ($44.4{\pm}13.9%$ vs $69.9{\pm}4.2%,\;2.48{\pm}0.98$ vs $3.51{\pm}0.62,\;1.76{\pm}0.71$ vs $3.38{\pm}0.92$, respectively, p<0.05). 2) In the phase angle analysis of LV, Standard deviation (SD), width of half maximum of phase angle (FWHM), and range of phase angle were significantly increased in patients with C-LBBB than in controls ($20.6{\pm}18.1$ vs $8.6{\pm}1.8,\;22.5{\pm}9.2$ vs $16.0{\pm}3.9,\;95.7{\pm}31.7$ vs $51.3{\pm}5.4$, respectively, p<0.05). 3) There was no significant difference in EF, PER, PFR between patients with the Wolff-parkinson-White syndrome and controls. 4) Standard deviation and range of phase angle were significantly higher in patients with WPW syndrome than in controls ($10.6{\pm}2.6$ vs $8.6{\pm}1.8$, p<0.05, $69.8{\pm}11.7$ vs $51.3{\pm}5.4$, p<0.001, respectively), however, there was no difference between the two groups in full width of half maximum. 5) Phase image analysis revealed relatively uniform phase across the both ventricles in patients with normal conduction, but markedly delayed phase in the left ventricle of patients with LBBB. 6) In 13 cases of WPW syndrome, the site of preexcitation could be localized in 10 cases (77%) by phase image analysis. Therefore, it can be concluded that phase image analysis can provide an accurate noninvasive method to detect the mechanical consequences of a wide variety of abnormal electrical activation in ventricles.

• Journal of the Korean Society for Library and Information Science
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• v.45 no.2
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• pp.209-228
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• 2011

Web search behavior has evolved. People now search using many diverse information devices in various situations. To monitor these scattered and shifting search patterns, an improved way of learning and analysis are needed. Traditional web search studies relied on the server transaction logs and single query instance analysis. Since people use multiple smart devices and their searching occurs intermittently through a day, a bundled query research could look at the whole context as well as penetrating search needs. To observe and analyze bundled queries, we developed a proprietary research software set including a log catcher, query bundling tool, and bundle monitoring tool. In this system, users' daily search logs are sent to our analytic server, every night the users need to log on our bundling tool to package his/her queries, a built in web survey collects additional data, and our researcher performs deep interviews on a weekly basis. Out of 90 participants in the study, it was found that a normal user generates on average 4.75 query bundles a day, and each bundle contains 2.75 queries. Query bundles were categorized by; Query refinement vs. Topic refinement and 9 different sub-categories.

• Journal of the Korean association of regional geographers
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• v.7 no.1
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• pp.51-66
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• 2001

The curriculum of integrated social studies is not conceptually established, but various forms pursuing so-called perfect integrated subject have appeared from elementary school to high school. But we cannot find out desirable integration in the elementary school though the apparent goal is to integrate all kinds of social concepts into one unit. The current method of integration has some problems over advantages people initially expected by integration. It is problematic in that students learn fragmental knowledges of geography without capturing the whole geographical concept structure or obtaining their own geographical viewpoint. Therefore, we purpose to reinterpret integration of social studies and reorganize the current textbook into the right direction under the assumption that simple mixture of knowledges is far from our goal of true integration. For this purpose, we suggest a new method for social studies as an integrated subject. Instead of providing knowledges unrelated to each other into one bundle, it helps students to see the real world in his own knowledge framework equipped with geographical viewpoint. The text we claim will show students that geography consists of three key concepts: physical environment, man and environment, and spatial structure. With this text, they will have an easy access to the relationships between key concepts and details, and between geographical concepts and similar concepts from other disciplines. The proposal contributes to both upcoming textbook development and classroom teaching by eliminating problems in the current social studies teaching.

• The Korean Society of Law and Medicine
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• v.18 no.1
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• pp.37-60
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• 2017

Ownership is the bundle of rights that allow a person or institute to use and control an object. As the biomedical science is advanced, we should consider whether human biological material should be recognized as property. Whether separated parts of the human body can be objects of ownership is a different issue. Many thought that separated parts of the human body could not be objects of ownership. This idea is primarily based on this thought: even if a piece of human biological material is separated from a person, it still relates to that person, and if treated as a thing, human dignity may be harmed. However, some commentators have admitted separated parts of the human body into the realm of property. Though a person owns his/her body or body parts, this does not mean that he/she can do anything he/she desires. There are many natural and social limitations to exercise the ownership of human biological material as discussed above. Human dignity is the core consideration whether or not we recognize that ownership of human biological material biomedical research and knowledge.