• Journal of Chest Surgery
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• v.26 no.3
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• pp.228-233
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• 1993

Patients with anomalous connection of the left coronary artery to the pulmonary artery are at risk for myocardial infarction, and early or sudden death. Between 1986 to 1992, a total of 4 of these patients underwent surgical intervention with various operative techniques at our institution. Age at operation ranged from 2 months to 43 years. Three infant patients had congestive heart failure, 2 of them had mitral regurgitaion, and 1 had ST-T change on elctrocardiogram. Operative techniques included direct coronary artery transfer to the aorta[n=2], intrapulmonary tunnel from the aortopulmonary window[n=1], coronary artery bypass using saphenous vein[n=1]. One deaths occured at 2 weeks after direct coronary arterial transfer due to respiratory failure caused by Respiratory Syncitial virus pneumonia. Supravalvar pulmoanry stenosis occured after intrapulmoanry tunnel. We recommend direct aortic implatation of the anomalous coronary artery at the time of diagnosis. Intrapulmonary tunnel from aortopulmonary window or subclavian-coronary anastomosis could be alternatives in whom aortic implantation is not feasible anatomically.

• Journal of Cerebrovascular and Endovascular Neurosurgery
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• v.25 no.3
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• pp.245-252
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• 2023

Carotid-cavernous fistulas, characterized by abnormal arteriovenous communication within the cavernous sinus (CS), can be classified as direct or indirect. Direct fistulas are defined as a direct connection between the internal carotid artery (ICA) and CS, whereas indirect fistulas result from an abnormal connection between the CS and dural arterial branches. The first-line treatment for both types of fistulas is endovascular intervention, most commonly accomplished through the transarterial and transvenous approaches of the conventional pathway, including the ICA, inferior and superior petrosal sinuses, or basilar plexus. Nonetheless, a retrograde approach through the superior ophthalmic vein may be necessary for individuals in whom conventional endovascular treatment fails. Herein, the current principles of surgical indication and technique are presented, along with case studies.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.698-702
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• 2005

Natural modes and responses of floating structures under wave loads are analyzed by direct method considering the stiffness of unit connections. Tow types of connection such as tandem connection and side by side connection are considered in numerical examples. By analyzing natural modes and connection forces, influences of connection stiffness on responses of floating structures are investigated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.895-902
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• 2005

This paper investigates the characteristics of dynamic responses of floating structures with connections under sea wave loads. Direct method using higher order boundary element method and finite element method is adopted for numerical analysis. 500 m-long VLFS with four units are considered in numerical analysis. Hinge connection and spring connection with various strength are considered as connection types. Displacements and stresses of VLFS according to the connection types are compared considering wave period and heading angle.

• Journal of the Korean GEO-environmental Society
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• v.8 no.1
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• pp.49-55
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• 2007

In order to utilize treads of waste tire as reinforcement material it is necessary to know the interface friction angle between tread surfaces and soil and tensile strength of connection joint of tire treads. In this research large direct shear tests were performed to get the interface friction angle between the inner and outer surfaces of treads and soil for different degree of compaction. From the large direct shear tests, the ratio of interface friction angle to the shear friction angle of sand, ${\delta}/{\phi}$, were 1.06 in outside surface of tire tread and 0.93 in inside surface of tire tread. For weathered granite soil the ratio of interface friction angle was 0.98 and 0.92 for outside and inside of tread, respectively. Also tensile tests were performed using universal testing machine for the connection joint of treads and Tirecell units using bolts. The tensile strength of connection joint increased with the number of bolts and with the sizes of washers. Connection by polypropylene ropes showed lower strength than those of bolts.

• Proceedings of the KOR-KST Conference
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• 2007.05a
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• pp.663-669
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• 2007

• 수도
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• v.24 no.3 s.84
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• pp.4-102
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• 1997

• 수도
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• v.24 no.3 s.84
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• pp.112-123
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• 1997

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1161-1168
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• 2018

On April 27 2018, North-South Korea agreed to establish the practical methods for connecting the railway in the inter-Korean summit talks. This is often reported that the train will be operated directly between Busan and Europe. However, there are many problems for the railway to directly connect between Busan and Europe. Because a train from Busan to Europe should pass through North Korea, China or Russia, and each national railway systems are different. Thus, South Korean railway has to study thoroughly an interoperability before railways directly operates between a nation and another. The standards and technical harmony for direct connection with a different railway network is very important, because a rail transport is a total network system. This paper surveyed a European railway interoperability and studied on the basic direct operation for the North-South Korean railway systems.

• Honam Mathematical Journal
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• v.30 no.1
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• pp.53-64
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• 2008

Lower dimensional cases of Einstein's connection were already investigated by many authors for n = 2, 3, 4, 5, 6. In the following series of two papers, we present a surveyable tensorial representation of 8-dimensional Einstein's connection in terms of the unified field tensor: I. The recurrence relations in 8-g-UFT II. The Einstein 's connection in 8-g-UFT In our previous paper [1], we investigated some algebraic structure in Einstein's 8-dimensional unified field theory (i.e., 8-g-UFT), with emphasis on the derivation of the recurrence relations of the third kind which hold in 8-g-UFT. This paper is a direct continuation of [1]. The purpose of the present paper is to prove a necessary and sufficient condition for a unique Einstein's connection to exist in 8-g-UFT and to display a surveyable tensorial representation of 8-dimensional Einstein's connection in terms of the unified field tensor, employing the powerful recurrence relations of the third kind obtained in the first paper [1]. All considerations in this paper are restricted to the first class only of the generalized 8-dimensional Riemannian manifold $X_8$, since the cases of the second class are done in [2], [3] and the case of the third class, the simplest case, was already studied by many authors.