• 경영과학
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• 제26권1호
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• pp.1-5
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• 2009

I study a solution concept which preserves the nice Nash equilibrium properties of two-person zero-sum games, and define a locally competitive equilibrium which is characterized by a saddle point with respect to the coordinates of strategies. I show that a locally competitive equilibrium shares the properties of uniqueness of equilibrium payoffs, interchangeablity of equilibrium strategies and convexity of the equilibrium set.

• 대한수학회지
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• 제44권2호
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• pp.455-466
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• 2007

The zero-distribution of the Fourier integral $${\int}^{\infty}_{-{\infty}}\;Q(u)e^{p(u)+^{izu}du$$, where P is a polynomial with leading term $-u^{2m}(m\;{\geq}\;1)$ and Q an arbitrary polynomial, is described. To this end, an asymptotic formula for the integral is established by applying the saddle point method.

• 대한수학회지
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• 제49권4호
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• pp.843-854
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• 2012

In this paper, the iterative Uzawa method with a modified Lagrangian functional is investigated to seek a saddle point for the semicoercive variational Signorini inequality.

• 복식
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• 제50권7호
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• pp.129-139
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• 2000

The Chonmachong (Tumulus No. 155 in Whangnam-dong, Kyungju, Korea), which was unearthed in 1973, is an ancient tomb built in the Shilla Era between the 5th∼6th centuries by the method of Juk-suk-mok-gwak. With the excavation of this tomb more than 11,500 articles of luxurious and splendid relics including gold and silver ornaments, weaponry and horse gears were obtained. Among the excavated articles, the saddle flap with a drawing of flying horse on it is the first relic of its kind from the Shilla Era. and 'Chonma'(a flying horse), the name of the tomb. was named after this drawing. The saddle flap is highly valuable in that it provides the idea of how goad the people of Shilla were at drawing. Although a lot of researches have been released about the relics from the Chonmachong, this study is to focus on the fabrics from the excavation, all of which are in the Kyongiu Museum's collection. The findings of this study are as follows : 1 The subject of this study is mainly on the fabrics used in horse gears, the pieces of cloth that were used to spread on a saddle or to underlay beneath a saddle. As the Shilla Dynasty tried to restrict excessive ornamentation on horses and it is assumed that the fabrics used are different. according to the social status. 2. The subject articles are four plain fabrics, three fabrics of combined -construction and one braid, the warp-faced compound woven silks of combined-construction was found for the first tinge in Korea, and is the typical quality sick with patterns woven with dyed threads in different colors. 3. It is ascertained by the Chonmachong excavation that polychrome woven silk was used not only for the clothes of the upper classes but also for the ornaments of their horses in the Era of the Three Kingdoms.

• 한국운동역학회지
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• 제22권1호
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• pp.65-73
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• 2012

The purpose of this study was to identify the saddle to pedal length contributing to successful performance in kayak using a kayak ergometer. Ten male elite kayak players participated in this study. players were tested on the kayak ergometer which was varied saddle to pedal length by the knee flexion angle(90deg; 120deg; 150deg) to measure stroke frequency, paddling amplitude, joint angle, RoM and angular velocity, foot pressure and force, iEMG using the 3D motion system, foot pressure system and EMG wireless system. At a results, rowing at 120deg on knee flexion angle showed higher stroke frequency and paddling amplitude than other knee flexion angles. RoM at upper extremity showed not significant difference between knee flexion angles. But there were significant differences in thorax and pelvis rotation RoM, knee flexion-extension RoM in each condition. In addition, foot pressure, force and iEMG were significantly different in knee flexion angles. Study showed that changed of saddle to pedal length affected rowing performance kinds of stroke frequency, paddling amplitude. The most important thing, increased range of motion in pelvic and thorax has occurred by force that generated foot-bar to seat. Not only that, but it seems to be attributed to a technical adaptation developed to maximum rowing performance.

• Journal of Chest Surgery
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• 제13권1호
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• pp.77-81
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• 1980

We present one case of 26-year-old male having saddle block combined with mitral valvular disease [NYHA Class IV] with auricular fibrillation. The most common cause of emboli is atrial fibrillation. The clinical manifestations of saddle emboli are relatively slow due to development of collateral circulation and large size of lumen of the aorta. The 5month duration of saddle emboli in this case led to severe atrophic changes, coldness, peripheral cyanosis on the both lower extremities, and flexion deformity on the knee and ankle joint of the left lower extremity. We planned staged operation for the saddle block and for mitral stenoinsufficiency and tricuspid insufficiency, because of poor general condition of the patient. The thromboembolectomy of aortic bifurcation was performed through the transabdominal approach without trial of Fogarthy catheter embolectomy, because of expectation of the secondary inflammatory changes of the vessel wall and thrombi which was 3 cm X 1 cm X 0.5 cm in size with irregular surfaced solid in consistency. 1 month later, after thromboembolectomy, mitral valve replacement and tricuspid annuloplasty were performed, with successful early operative result. During operation organized thrombi [1 cm X 0.5 cm] in the left auricle was removed. We wonder if simple management using Fogarthy catheter might be possible to remove the thromboemboli instead of thromboembolectomy by aortotomy in this case.

• Structural Engineering and Mechanics
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• 제14권2호
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• pp.171-190
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• 2002

Two cases of design are performed for the hyperbolic paraboloid saddle shell (Lin-Scordelis saddle shell) and the hyperbolic cooling tower (Grand Gulf cooling tower) to check the design strength against a consistent design load, therefore to verify the adequacy of the design algorithm. An iterative numerical computational algorithm is developed for combined membrane and flexural forces, which is based on equilibrium consideration for the limit state of reinforcement and cracked concrete. The design algorithm is implemented in a finite element analysis computer program developed by Mahmoud and Gupta. The amount of reinforcement is then determined at the center of each element by an elastic finite element analysis with the design ultimate load. Based on ultimate nonlinear analyses performed with designed saddle shell, the analytically calculated ultimate load exceeded the design ultimate load from 7% to 34% for analyses with various magnitude of tension stiffening. For the cooling tower problem the calculated ultimate load exceeded the design ultimate load from 26% to 63% with similar types of analyses. Since the effective tension stiffening would vary over the life of the shells due to environmental factors, a degree of uncertainty seems inevitable in calculating the actual failure load by means of numerical analysis. Even though the ultimate loads are strongly dependent on the tensile properties of concrete, the calculated ultimate loads are higher than the design ultimate loads for both design cases. For the cases designed, the design algorithm gives a lower bound on the design ultimate load with respect to the lower bound theorem. This shows the adequacy of the design algorithm developed, at least for the shells studied. The presented design algorithm for the combined membrane and flexural forces can be evolved as a general design method for reinforced concrete plates and shells through further studies involving the performance of multiple designs and the analyses of differing shell configurations.

• 한국응급구조학회지
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• 제23권2호
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• pp.99-107
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• 2019

Purpose: This study aimed to identify the position for the most accurate head-up cardiopulmonary resuscitation (CPR) by comparing saddle position CPR (SPCPR) and traditional CPR (TCPR). Methods: Sixty certified persons who completed a basic life support provider course between May 1 and June 21, 2019 were enrolled in the study. The participants were asked to perform 2 minutes of CPR, and the depth of chest compression, rate, position, full release, and hands off time were assessed. Accuracy was evaluated based on data collected from a smart phone application connected to the manikin via bluetooth and analyzed using frequency, percentage, t-test, analysis of variance and ${\chi}^2$. Results: The accuracy of chest compression was statistically significantly higher for SPCPR, 63.03%[${\pm}8.75$] for SPCPR and 55.50%[${\pm}10.17$] for TCPR [t=3.074, p=.003]. The depth of chest compression was statistically significantly greater for SPCPR, 4.51cm[${\pm}0.45$] for SPCPR and 4.16cm[${\pm}0.61$] for TCPR [t=2.503, p=.015]. The rate of chest compression was statistically significantly higher for TCPR, 105/min[${\pm}10.79$] for SPCPR and 111/min[${\pm}11.57$] for TCPR [t=-2.008, p=.049]. Accuracy of position of chest compression was statistically significantly higher for SPCPR, 96.10%[${\pm}13.73$] for SPCPR and 79.93%[${\pm}30.34$] for TCPR [t=2.659, p=.011]. Accuracy of full release was higher with SPCPR, with 86.30%[${\pm}30.53$] for SPCPR and 71.10%[${\pm}36.05$] for TCPR, but the difference was not statistically significant [t=1.762, p=.083]. Conclusion: Saddle position CPR was found to be more accurate than TCPR in the performance of manual head-up CPR.

• 한국전산구조공학회논문집
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• 제34권4호
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• pp.191-197
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• 2021

분자동역학에서의 원자들의 유도전하를 계산하기 위해서는 유도전하를 미지수로 하는 선형방정식을 풀어야 하는데 원자들의 위치가 변화할 때마다 필요한 계산이므로 상당한 계산비용이 요구된다. 따라서 효율적인 유도전하 계산 방법은 다양한 시스템을 해석하기 위해서 필수적이다. 본 연구에서는 constraints가 존재하는 Lagrange 방정식의 해에 대한 선형 시스템, 즉 saddle point를 가지는 문제를 해결하기 위해서 Uzawa method를 도입하였다. Uzawa 매개변수가 수렴 속도에 영향을 미치는 단점을 극복하고 행렬 연산의 효율성을 위해서 Schur complement와 preconditioned conjugate gradient (PCG) 방법을 통해 계산의 효율성을 극대화하는 가속 Uzawa algorithm을 적용한다. 두 금속 나노입자가 전기장에 놓여진 분자동역학 수치모델을 통해서 제시된 방법이 유도전하계산의 수렴성, 효율성 측면에서 모두 향상된 결과를 도출함을 확인하였다. 특히 기존의 가우스 소거법에 의한 계산보다 약 1/10으로 계산비용이 절감되었고, 기본 Uzawa method에 비하여 conjugate gradient (CG)의 높은 수렴성이 입증되었다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.677-680
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• 2008

본 논문에서는 다층매질 안에 위치한 안테나의 방사특성을 해석하고 있다. 접지면이 없는 유전체 기판에 인쇄된 안테나의 경우, 매질의 구성은 공기층을 포함하여 3층매질이 되며 이러한 3층매질의 Green 함수은 Sommerfeld적분식으로 표현되기 때문에 해석이 매우 복잡해진다. 그러나 안테나위 방사특성을 해석하는데 있어서는 적분식의 조건이 잘 일치한다면 Sadddle-point법을 이용하여 근사할 수 있다. 본 연구에서는 이와 같은 근사법을 적용하여 접지면이 없는 유전체 기판에 놓인 각종 안테나의 방사패턴 특성을 해석한다. 또한 기판으로 사용하는 유전체의 파라미터를 달리하여 방사특성을 검토한다.