• Journal of applied mathematics & informatics
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• v.14 no.1_2
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• pp.173-183
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• 2004

Data envelopment analysis(DEA) is a mathematical programming approach to asses s relative efficiency of a group of decision-making units. In view of the defects of existing models in evaluating efficiency of the system with P independent subsystems, Yang et al. [10] introduced YMK model with the assumption that decision-making unit(DMU) is independent of each other. But in some production systems, decision-making units usually have some relationships in this way or that. In this paper, DEA model is given by assuming that DMUs can cooperate with others in its subgroups. Some property and the efficiency relationship of the whole system and its subsystems are given.

• Smart Structures and Systems
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• v.19 no.5
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• pp.463-472
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• 2017

In a previous study, the potential of damping suspension bridges with active stay cables has been evaluated on a numerical model of a suspension bridge, and demonstrated experimentally on a laboratory mockup. In this paper, we extend our study to explore two different configurations of the active stay-cables: one classical configuration, corresponding to attaching the active stay-cables between the top of the pylons and the deck (configuration I) and, another configuration, consisting of attaching the stay-cables between the base of the pylons and the catenary (configuration II). The analysis confirmed that both configurations are effective with a slight superiority of the second configuration. The study is conducted numerically and experimentally on a suspension bridge mock-up, by considering two types of active stay-cables. The experimental results confirmed the numerical predictions, and demonstrated the effectiveness of the second configuration.

• Structural Engineering and Mechanics
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• v.65 no.3
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• pp.251-261
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• 2018

Self-centering concentrically braced frames (SCCBFs) are emerging as high performance seismically resistant braced framing system, due to the capacity of withstanding strong earthquake attacks and promptly recovering after events. To get a further insight into the seismic performance of SCCBFs, systematical evaluations are currently conducted from the perspective of modal contributions. In this paper, the modal pushover analysis (MPA) approach is utilized to obtain the realistic seismic demands by summarizing the contribution of each single vibration mode. The MPA-based results are compared with the exact results from nonlinear response history analysis. The adopted SCCBFs originate from existing buckling-restrained braced frames (BRBF), which are also analyzed for purpose of comparison. In the analysis of these comparable framing systems, interested performance indices that closely relate to the structural damage degree include the interstory drift ratio, floor acceleration, and absorbed hysteretic energy. The study shows that the MPA approach produces acceptable predictions in comparison to the exact results for SCCBFs. In addition, the high-modes effect on the seismic behavior increases with the building height, and is more evident in the SCCBFs than the BRBFs.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2871-2877
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• 2013

Objectives: To evaluate the safety, efficacy, and invasiveness of lobectomy by video-assisted thoracoscopic surgery (VATS) in the treatment of stage I/II non-small cell lung cancer (NSCLC). Methods: A total of 148 patients presenting with Stage I or II NSCLC were enrolled into our study, comprising 71 who underwent VATS and 77 patients undergoing conventional thoracotomic lobectomy, in combination with systematic lymph node resection. Results: It was found that VATS was superior to conventional thoracotomy in terms of the duration of surgery, intraoperative blood loss, frequency of the need to administer postoperative analgesia, thoracic intubation indwelling time, post-operative hospital stay, and survival rate (P<0.05). We saw no obvious difference in the number of resected lymph nodes with either approach. Conclusions: VATS lobectomy is a safe and reliable surgical approach for the treatment of Stage I/II NSCLC, characterized by significantly minimal invasiveness, rapid post-operative recovery, and markedly lower loss of blood.

• The Journal of Korean Medicine
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• v.22 no.4
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• pp.114-120
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• 2001

Objectives : Man adapts himself to nature, so accordingly as he grows up, changes of body composition appear. This study measured the changes of body compositions on the ground of Sasang constitution and seasons Methods : 253 middle school students who live in Busan were studied from the 20th of March, 1999 to the 20th of March, 2001. We measured height and body compositions with Inbody 3.0, six times during that period. Results : According as they grew up, total body water, muscle area, body weight, BMI (Body Mass Index), BMR (Basal Metabolic Rate), ACM (Arm Muscle Circumference), and BCM (Body Cell Mass) increased, but fat body weight ratio decreased. From March to June, total body water, muscle area, height, ACM, and BCM increased. From September to December fat body weight, fat body weight ratio, waist hip ratio increased as compared with other seasons. Height of Soyangin and BMI of both Soyangin and Taeumin increased more than those of other groups, with statistical significance Conclusions : The growth of man is adapting oneself to changes of nature, and it corresponds to the theory of (correspondence between man and universe).

• Journal of Korean Neurosurgical Society
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• v.57 no.3
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• pp.219-220
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• 2015

Variations in the course and distribution of common palmar digital nerves and arteries are rare. A classic common palmar digital nerves and arteries are defined as concomitant. During routine dissection classes to undergraduate medical students we observed formation of each common palmar digital nerve divided into 2 or 3 branches and formed a ring enclosing the corresponding common palmar digital artery. Knowledge of the anatomical variations of the common palmar digital nerves and arteries is crucial for safe and successful hand surgery.

• Bulletin of the Korean Mathematical Society
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• v.53 no.5
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• pp.1457-1469
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• 2016

In this paper, we study a class of Finsler metric. First, we find some rigidity results of the dually flat (${\alpha}$, ${\beta}$)-metric where the underline Riemannian metric ${\alpha}$ satisfies nonnegative curvature properties. We give a new geometric approach of the Monge-$Amp{\acute{e}}re$ type equation on $R^n$ by using those results. We also get the non-existence of the compact globally dually flat Riemannian manifold.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.673-677
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• 2009

In this paper, a transmitting process of a sequence of holograms describing 3D moving objects over the communicating wireless-network system is presented. A sequence of holograms involves holograms is transformed into a bit stream data, and then it is transmitted over the wireless LAN and Bluetooth. It is shown that applying this technique, holographic data of 3D moving object is transmitted in high quality and a relatively good reconstruction of holographic images is performed.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.429-434
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• 2009

We introduce an instant and intuitive shadowing technique for CACAni System. In traditional 2D Anime, since all frames are drawn by hand it takes long time to create an entire animation sequence. CACAni System reduces such a production cost by automatic inbetweening and coloring. In this paper, we develop a shadowing technique that enables CACAni users to easily create shadow for character or object in the image. The only inputs required are sequences of character or object layers drawn in CACAni System with alpha value. Shadows are automatically rendered on a virtual plane based on these inputs. They can then be edited by CACAni users. Achieving this, CACAni System is able to handle instant shadowing and intuitive editing in a short time.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.819-821
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• 2002

Photoluminescenc (PL) and low-voltage cathodoluminescence (CL) characteristics of $[xSrTiO_3+(1-x)Li_2TiO_3]:Pr^{3+}$ and $[xSrTiO_3+(1-x)Na_2TiO_3]:Pr^{3+}$ systems were investigated. The red luminescence intensities of these compounds are enhanced remarkably by the incorporation of $Li^+$ or $Na^+$ ion as compared to that of $SrTiO_3:Pr^{3+}$. The enhanced luminescence is speculated to result from both the charge compensation of $Pr^{3+}$ site and oxygen vacancies generated in the lattices by $Li^+$ or $Na^+$ ion.