• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.412-419
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• 1993

The transient responses of a linear system having undesired disturbances are dominantly governed by the system's left eigenstructure(eigenvalues/left eigenvectors). In control system design problem of altering the transient response of the system, both the controllability and the disturbance suppressibility, should be considered simultaneously to obtain a robust, effective controller. The controllability of the system may be degraded if the left eigenstructure is chosen to suppress the disturbance, or vice versa. In this paper, first, proposed are a modal disturbance suppressibility measure and an improved version of the modal controllability measure suggested by Hamdan and Nayfeh. Second, a simple and general left eigenstructure assignment scheme, considering both the proposed modal disturbance suppressibility measure and the improved version of modal controllability measure, is suggested. When the previous works are applied to assign the left eigenvectors may differ from the desired ones. But the proposed left eigenstructure assignment scheme makes it possible to achieve the desired colsed-loop eigenvalues exactly, provided the desired left eigenvectors reside in the achievable subspace. In case the desired left eigenvectors do not reside in the achievable subspace, the closed-loop eigenvalues are achieved exactly and the left eigenvectors are assigned to the best possible set of eigenvectors in the least square sense. Finally, a numerical example is included to confirm and demonstrate the usefulness of our propositions and to illustrate the proposed design scheme.

• Journal of Korean Society of Transportation
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• v.14 no.4
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• pp.91-106
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• 1996

This paper deals with on the efficiency questions of the left-turn prohibit at an isolated intersection and a corridor with 5-phase signal system. Its objectives are three-fold ; (1) to analyze the efficiency of the left-turn prohibit with the use of an imaginary network, (2) to evaluate various factors under consideration in decision making on the left-turn prohibit, (3) to provide a framework for estimating and evaluating overall impacts of the left-turn prohibit in traffic network. the major findings using an imaginary network and computer packages such as MINUTP, TRANSYT-7F and STATGRAPH are followings. First, left-turn prohibit reduces cycle length by 33 seconds and delay time per vehicle by 36 seconds at an isolated intersection, and cycle length by 31 seconds and delay time per veicle by 43 seconds along a corridor. Second, total vehicle mile of travel and total travel time at an isolated intersection seem up to increase 38.85 miles(57.36km), 14.4 hour on the average, Regarding to a corridor, total vehicle mile of travel is increased by 50.14 miles(80.22km), but total travel time is decreased by129.9 hours. Third, the efficiency of left-turn prohibit are affected the following eight factors including left-turn volume(veh/hr) and ratio(%), average delay time per vehicle(sec/veh) and others. Finally, several simple and multiple regression models to evaluate the impacts on the left-turn prohibit are formulated from the above eight factors. It can be expected that these models will take an important role in decision-making of left-turn prohibit.

• The Korean Journal of Nuclear Medicine
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• v.20 no.1
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• pp.85-91
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• 1986

In detecting, localizing and quantitating cardiac shunts, radionulide angiocardiography has been known to be a simple and safe method compared with oxymetry method. To ascertain the availability of the results obtained by radionuclide angiocardiography for the evaluation of patients with cardiac shunt, author compared the Qp/Qs ratios(pulmonary to systemic flow ratios) obtained by radionuclide angiocardiography with the results of oximetry method in 40 patients with left to right shunt, and also compared the results of radionuclide angiocardiography examined before and after shunt operation in 8 patients. The results were as follows: 1) Of the 161 patients examined radionuclide angiocardiography, 98 were thought to have cardiac shunts: right to left shunt id 27, left to right shunt in 71. Of the 71 patients who had left to right shunt, 40 who were examined with both radionuclide angiocardiography and oxymetry had following congenital heart disease: VSD in 21, ASD in 9 and PDA in 10. 2) Comparison of Qp/Qs ratios obtained during radionuclide angiocardiography and oxymetry revealed good correlation (linear regression analysis yielded correlation coefficient of 0.80) in 32 patients whose Qp/Qs ratio obtained during oxymetry were below 3.0, but very poor correlation in 8 patients whose Qp/Qs ratios were above 3.0 3) Radionuclide angiocardiography is a relatively safe and simple method in postoperative evaluation of patients with cardiac shunt.

• Journal of Chest Surgery
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• v.22 no.5
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• pp.816-822
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• 1989

Aneurysms of the descending thoracic aorta can be caused by various etiologies. So, its abrupt rupture leads life-threatening state, it must be operated as soon as possible. Surgical treatment of the descending thoracic aortic aneurysm requires temporary cross-clamping of major artery. The obligatory occlusion of the descending thoracic aorta during management causes proximal arterial hypertension and distal arterial hypotension. The former may leads to left ventricular failure, or cerebrovascular accident, whereas the latter may leads to spinal cord ischemia or renal injury. Some have recommended insertion of temporary shunt around the occluded descending aorta to prevent above problems. Still others would favor expeditious operation employing simple aortic occlusion during the repair of the descending aorta. Recently we had experienced two cases of dissecting aneurysms of descending thoracic aorta which performed aortoplasty with Gore-Tex conduit under simple aortic occlusion. The one was 34-year-old female patient with traumatic dissecting aortic aneurysm [5 em X 5 cm] on the descending thoracic aorta distal to the origin of the left subclavian artery and the other was 58-year-old female patient with atherosclerotic dissecting descending thoracic aortic aneurysm [6 cmX7 cm] and diffuse abdominal aortic aneurysms [3X5 cm]. Both patients performed standard left posterolateral thoracotomy. After the aneurysmal sac was mobilized, occluding vascular clamps were placed on the transverse aorta proximal to the origin of the left subclavian artery, and on the distal descending aorta without adjuvant bypass procedures for 31 and 32 minutes, respectively, and the aneurysmal sac was repaired with 18 mm ringed Gore-Tex conduit graft. Both patients postoperative courses were uneventful.

• Journal of the Korean Society of Costume
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• v.38
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• pp.337-358
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• 1998

Underlying principles on the origin and establishment of the concept fo Right-and-Left (R-&-L) in Korean traditional costume is studied in this paper. Among Korean traditional costumes, ordinary and funeral costumes are considered in this study. Thed concept of R-&-L expanded into different elements of daily life among Korean people is also considered as a process of conceptual development : starting from astron-omy principle, then developed to pragmatism principle, and expanded to abstraction principle. No evidence on the case where the astro-omy principle was directly applied to was found in this study. In most cases, pragmatism and abstraction principles are observed as underly-ing principles. In ordinary costumes, pragmatism principle is the fundamental base for R-&-L through right-hand-use rule. Even though abstraction prin-ciple was found in some ordinary costumes, we believe that this was generated for adding more meanings in addition to the pragmatism principle. In funeral costumes, pragmatism principle was almost totally ignored unlike in ordinary costumes because the funeral rite was performed though formality with abstract thoughts. The abstraction principle was exercised with the form of simple-discrimination rule based on the dual system along with Yin-Yang related cultural rules such as‘Yang-left-and-Yin-right’or‘father-left-and-mother-right’. However, the case where‘left-male-and-right-female’rule is applied to was not found in this study.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.669-685
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• 1997

The present study was performed to evaluate the effects of xylazine and tiletamine + zolazepam on echocardiograms before and after experimental myocardial infarctions in clinically normal dogs taken preliminary examinations related to cardiac function. The results are as follows. With xylazine administration, left ventricle end-diastolic dimension, left ventricle end-systolic dimension, left atrium/aorta, ejection time and velocity of circumferential fiber shortening increased and mitral valve CD slope, % delta D decreased(p<0.01). In tiletamine+zolazepam administered group, interventricular septum amplitude(p<0.01), mitral valve DE slope(p<0.05) and ejection time(p<0.01) decreased and left atrium/aorta, ejection time also decreased compared with xylazine group(p<0.01). In 48 hours after experimental myocardial infarction group, anterior aortic wall amplitude decreased compared with control, xylazine, tiletamine + zolazepam group, respectively(p<0.01). Posterior aortic wall amplitude decreased compared with control(p<0.01). Left ventricle end systolic dimension increased compared with control and tiletamine + zolazepam group, respectively(p<0.01). Left ventricular posterior wall end systolic dimension decreased compared with control(p<0.01). Left ventricular posterior wall amplitude decreased compared with control and tiletamine+zolazepam group(p<0.01). Left atrium/aorta decreased compared with xylazine group(p<0.01). % thickening left ventricular posterior wall decreased compared with control(p<0.05). % delta D decreased compared with control and tiletamine+zolazepam group(p<0.01). Ejection time decreased compared with xylazine(p<0.01). Velocity of circumferential fiber shortening increased compared with control and tiletamine + zolazepam group(p<0.01). With xylazine administration 48 hours after experimental myocardial infarction, anterior aortic wall amplitude, posterior aortic wall amplitude decreased compared with control(p<0.01). Left ventricle end-diastolic dimension increased compared with control(p<0.01). Left ventricle end-systolic dimension increased compared with control and tiletamine + zolazepam group, respectively(p<0.01). Left ventricular posterior wall end-systolic dimension and left ventricular posterior wall end-diastolic dimension decreased compared with control(p<0.01). Left atrium/aorta decreased compared with xylazine group(p<0.01). % thickening left ventricular posterior. wall(p<0.05) and % delta D(p<0.01) decreased compared with control. Velocity of circumferential fiber shortening increased compared with tiletamine + zolazepam group(p<0.01). With tiletamine + zolazepam administration 48 hours after experimental myocardial infarction, anterior aortic wall amplitude decreased compared with control, xylazine and tiletamine+zolazepam group, respectively(p<0.01). Posterior aortic wall amplitude decreased compared with control(p<0.01). Left ventricle end-systolic dimension increased compared with control and tiletamine+zolazepam group(p<0.01). Left ventricular posterior wall end-systolic dimension, left ventricular posterior wall end-diastolic dimension and interventricular septum amplitude decreased compared with control(p<0.01). Left atrium/aorta decreased compared with xylazine group(p<0.01). % delta D decreased compared with control and tiletamine + zolazepam group(p<0.01). Ejection time decreased compared with xylazine group and velocity of circumferential fiber shortening increased compared withtiletamine+zolazepam group(p<0.01). Conclusively, echocardiography was proved to be a useful, diagnostic, non-invasive and simple method for establishing the diagnosis of myocardial infarction and evaluating the effects of drug on cardiac function before and after myocardial infarction.

• Bulletin of the Korean Mathematical Society
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• v.44 no.2
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• pp.359-367
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• 2007

We consider the intuitionistic fuzzification of the concept of several ${\Gamma}$-ideals in a ${\Gamma}$-semigroup S, and investigate some properties of such ${\Gamma}$-ideals.

• Transactions of Materials Processing
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• v.15 no.6 s.87
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• pp.467-472
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• 2006

The forming limit diagram of tube is required for the part design and the formability analysis of tube hydroforming. The finite element analyses of simple bulge test were done to obtain the various strain combinations on FLC. The finite element analysis results were shown that the bursting at various strain combinations could be induced by simple bulge test. The experiment oi tube bulge test was carried out according to the test condition that obtained from finite element analysis and the left hand side of forming limit diagram was built.

• Journal of applied mathematics & informatics
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• v.27 no.5_6
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• pp.1447-1457
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• 2009

In this paper we define intuitionistic fuzzy interior ideals in ordered semigroups. We prove that in regular(resp. intra-regular and semisimple) ordered semigroups the concepts of intuitionistic fuzzy interior ideals and intuitionistic fuzzy ideals coincide. We prove that an ordered semi group is intuitionistic fuzzy simple if and only if every intutionistic fuzzy interior ideal is a constant function. We characterize intra-regular ordered semi groups in terms of interior (resp. intuitionistic fuzzy interior) ideals.

• Imaging Science in Dentistry
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• v.32 no.4
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• pp.227-230
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• 2002

The central odontogenic fibroma is a rare benign neoplasm, and considered to be derived from the mesenchymal tissue of dental origin. It is a poorly defined tumor of the jawbones which has only been infrequently reported in the literature. We report a histologically proven case of simple-type central odontogenic fibroma, which affected the left canine-premolar region of the maxilla in a 52-year-old woman.