• Journal of Korean Society for Quality Management
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• v.46 no.4
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• pp.973-982
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• 2018

Purpose: The purpose of this study is to develop an effective simulation modeling formalism for autonomous control systems, such as unmanned aerial vehicles and unmanned surface vehicles. The proposed simulation modeling formalism can be used to evaluate the quality and effectiveness of autonomous control systems. Methods: The proposed simulation modeling formalism is developed by extending the classic DEVS (Discrete Event Systems Specifications) formalism. The main advantages of the classic DEVS formalism includes its rigorous formal definition as well as its support for the specification of discrete event models in a hierarchical and modular manner. Results: Although the classic DEVS formalism has been a popular modeling tool, it has limitations in describing an autonomous control system which needs to make decisions by its own. As a result, we proposed an extended DEVS formalism which enables the effective description of internal decisions according to its conditional variables. Conclusion: The extended DEVS formalism overcomes the limitations of the classic DEVS formalism, and it can be used for the effectiveness simulation of autonomous weapon systems.

• Journal of Mechanical Science and Technology
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• v.14 no.11
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• pp.1225-1231
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• 2000

This paper proposes a V-shaped Lyapunov function approach for the model-based control of flexible-joint robots, in which a new model-based nonlinear control scheme is designed based on a V-shaped Lyapunov function. The proposed control guarantees global asymptotic stability for link trajectory control while keeping all internal signals bounded. Since joint flexibility is used as a control parameter, the proposed control is not restricted by the degree of joint flexibility and be applied to flexibility-joint, partly-flexibility, or rigid-joint robots without modification. the effectiveness of the proposed control has been by computer simulation.

• 제어로봇시스템학회:학술대회논문집
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• 1999.10a
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• pp.306-308
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• 1999

Recently 2DOF control system has been widely recognized to be efficient. The major merit of 2DOF control is the independency between tracking performance and feedback performance. But the design of two parameters of 2DOF control system is not much considered about the relation between the identification and the design. In the field of robust control, the joint control, which can combine the identification with the design, is investigated. Then are apply the joint control to the design of 2DOF control system, and verify the effectiveness by some simulation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.9
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• pp.1461-1467
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• 2001

This paper proposes a new approach for the ant-swing control of overhead cranes. The proposed control consists of a model-based anti-swing control scheme and a practical path planning scheme. The anti-swing control scheme is designed based on the Lyapunov stability theorem; the proposed control does not require the usual constraints of small load mass, small load swing, slow hoisting speed, and small hoisting distance, but guarantees asymptotic stability while keeping all internal signals bounded. The path planning scheme is designed based on the concepts of minimum-time control and anti-swing control; the proposed path planning generates near-minimum-time trajectories independently of hoisting speed and distance. The effectiveness of the proposed control is shown by computer simulation.

• The Journal of Internal Korean Medicine
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• v.39 no.4
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• pp.520-549
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• 2018

Objectives: We performed a systematic review and meta-analysis to explore the recent clinical research trends regarding the effects of traditional herbal medicine (THM) on chemotherapy-induced leukopenia. Methods: Randomized controlled trials that verified effects of herbal medicine treating chemotherapy induced leukopenia were included in the study. A literature search was performed in the English, Chinese, and Korean databases for papers published from January 1, 2007, to September 1, 2017. The selected literature was assessed by Cochrane's Risk of Bias (RoB). Results: Forty-two of 232 randomized controlled trials met the inclusion criteria. The most commonly used herbal prescriptions called '升白湯 (shengbai decoction)' which means elevating the numbers of White blood cells (WBCs). And the mostly included herbs such as Astragali Radix, Angelicae Gigantis Radix, Atractylodis Rhizoma Alba, Codonopsis Pilosulae, Glycyrrhizae Radix, Ligustri Lucidi Fructus are commonly used to elevate qi, blood and yin. The count of WBC in peripheral blood, the level of leukopenia presented in WHO (World Health Organization), and clinical symptoms were used to evaluate the treatments. The effective rate was 68.6-98.18% and the effectiveness was significantly higher in the intervention group than in the control group in 38 articles (p<0.05). No serious adverse events were reported. Only five articles (5/42, 11.9%) were rated as having adequate methodological quality with a low level of bias. Conclusion: Some traditional herbal medicines may be effective as therapeutic treatments for chemotherapy-induced leukopenia, but the majority of reviewed studies were of poor quality. The present findings need to be confirmed by rigorously conducted high-quality trials, including pharmacokinetic studies, to confirm the absence of interactions between traditional herbal medicine agents and chemotherapy.

• The Journal of Internal Korean Medicine
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• v.38 no.1
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• pp.48-63
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• 2017

Objectives: This study was performed to review the recent clinical research trends of the effects of herbal medicine treatment on chronic pancreatitis in China. Methods: We searched for clinical studies about chronic pancreatitis from the China Academic Journal (CAJ) of the China National Knowledge Infrastructure (CNKI) from January 1, 2005, to August 1, 2016. Results: Thirty-seven papers were selected from 126 studies. The most commonly used herbal prescriptions included Bupleuri Radix (柴胡), Paeoniae Radix Alba (白芍藥), Glycyrrhizae Radix (甘草), Scutellariae Radix (黃芩), Aucklandiae Radix (木香), and Rhei Rhizoma (大黃). Qingyi-tang (淸胰湯) was the most frequently used herbal prescription. Clinical symptoms, physicochemical examination, radiological examination, and relapse were used to evaluate the treatments. The effective treatment rate was 77.5-100%, and effectiveness in the experimental group was significantly higher than in the control group in 15 papers (p<0.05). Conclusions: Herbal medicine treatment has been shown as an effective treatment for chronic pancreatitis. In the future, more scientifically designed clinical studies should be performed to prove the effectiveness of herbal medicine treatment on chronic pancreatitis. These research results can be utilized in other clinical studies and in the treatment of chronic pancreatitis.

• International Journal of Control, Automation, and Systems
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• v.2 no.2
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• pp.144-155
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• 2004

This paper addresses the issue of position control of a chain of multiple mass-spring-damper (CMMSD) units which can be found in many physical systems. The dynamic model of a CMMSD system with any degrees of freedom is expressed in a closed-form for the convenience of the controller design. Backstepping and model reference adaptive control (MRAC) approaches are then used to develop two adaptive output feedback controllers to control the position of a CMMSD system. The proposed controllers rely on the measurements of the input (force) and the output (position of the mass unit at the end of the chain) of the system without the knowledge of its parameters and internal states. Simulations are used to verify the effectiveness of the controllers

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.7 s.178
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• pp.1689-1696
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• 2000

This paper proposes a new adaptive control scheme for flexible-link robots. A model-based nonlinear control scheme is designed based on a V-shape Lyapunov function, and then the nonlinear control i s extended to a model-based adaptive control to cope with parametric uncertainties in the dynamic model. The proposed control guarantees the global exponential or global asymptotic stability of the overall control system with all internal signals bounded. The effectiveness of the proposed control is shown by computer simulation.

• International journal of advanced smart convergence
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• v.10 no.2
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• pp.175-186
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• 2021

We have studied the speed regulation of the permanent magnet synchronous motor (PMSM) servo system in this paper. To optimize the PMSM servo system's speed-control performance with disturbances, a non-linear speed-control technique using a back-propagation neural network (BP-NN) algorithm forthe controller design of the PMSM speed loop is introduced. To solve the slow convergence speed and easy to fall into the local minimum problem of BP-NN, we develope an improved BP-NN control algorithm by limiting the range of neural network outputs of the proportional coefficient Kp, integral coefficient Ki of the controller, and add adaptive gain factor β, that is the internal gain correction ratio. Compared with the conventional PI control method, our improved BP-NN control algorithm makes the settling time faster without static error, overshoot or oscillation. Simulation comparisons have been made for our improved BP-NN control method and the conventional PI control method to verify the proposed method's effectiveness.

• The Journal of Internal Korean Medicine
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• v.44 no.1
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• pp.12-34
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• 2023

Objective: This study was conducted to evaluate the effectiveness of the combination therapy of Yukmijihwang-tang and Western medicine on primary glomerulonephritis. Methods: We conducted a search using keywords, such as Yukmijihwang-tang and Liuwei Dihuang, in eight databases (CNKI, CiNii, Pubmed, Embase, Cochrane, Science On, OASIS, RISS). There was no limit to the publication period of the papers. A meta-analysis was conducted and classified according to the outcome measurements, such as the total effective rate (TER), serum creatinine (SCr), and blood urea nitrogen (BUN). Data analysis was performed using the RevMan 5.4.1 software, and Cochrane's risk of bias (ROB) was used to assess the quality of the papers. Results: A total of 12 randomized control trials were selected. The meta-analysis showed that the treatment group combining Yumijihwang-tang and Western medicine was more efficient than the control group using Western medicine alone (RR: 1.29, CI: 1.20 to 1.39 p=<0.00001). The treatment group also reduced the BUN (MD: -2.40, CI: -2.90 to -1.89, p<0.00001) and Scr (MD: -33.34, CI: -40.85 to -25.82, P<0.00001) more than the control group. Conclusion: This study suggests that the combination therapy of Yukmijihwang-tang with Western medicine is effective in treating primary glomerulonephritis. However, these findings should be interpreted cautiously due to the unknown or high risk of bias in the included trials.