• Proceedings of the KSME Conference
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• 2000.04a
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• pp.511-516
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• 2000

In order to not only perform as a extreme model under the severe operating condition but also acquire more diverse and advanced control capability utilizing high compliance, active vibration control of a flexible 2-link robot manipulator are investigated. Multi variable-structured frequency shaped optimal sliding mode is proposed for the flexible robot manipulator like control system, whose control variables, an angular motion of joint and vibration of flexible link, have to be controlled simultaneously by one control torque at a driving joint. The control system is divided into two subsystems, a control input related subsystem and an added subsystem. The proposed sliding mode, composed of multi control variables, makes optimized relation between subsystems and a individual control input, thus, the sliding mode controller can compensate whole dynamics of each subsystems simultaneously. And the possibility and effectiveness are verified by vibration control of a manipulator having two flexible links. Simulation and experiment results show that the proposed control scheme achieves the purpose effectively.

• The Journal of Korea Robotics Society
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• v.16 no.2
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• pp.147-154
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• 2021

One of the most challenging issues when robots interact with the environment is to establish contact quickly and avoid high impact force at the same time. The proposed method implements the passive suspension system using the redundancy of the torque-controlled robot. Instead of utilizing the actual mechanical compliance, the distal joints near the end-effector are controlled to act as a virtual spring-damper system with low feedback gains. The proximal joints are precisely controlled to push the mid-link, which is defined as the boundary link between the proximal and distal joints, towards the environment with high feedback gains. Compared to the active compliance methods, the contact force measurements or estimates are not required for contact establishment and the control time delay problems do not occur correspondingly. The proposed method was applied to the landing foot control of the 12-DoF biped robot DYROS-RED in the simulations. In the results, the impact force during landing was significantly reduced at the same collision speed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.284-284
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• 2009

The LED of cultivation edible plants was compliance the variable of the photo-receptor pigment with the red light source and ultra red light source from long wave region. The mechanism of cultivation edible plants for each part was necessary the wavelength unit which is appropriate, the illuminant source, motor control and lens design of LED light source about plant. The photo-receptor pigment induces for a long daytime recognition, seed germination and anthesis etc, induction years exists in the state which is an inactivity within the cells and in compliance with the red light source to be converted in active

• Journal of the Korean Society of Propulsion Engineers
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• v.7 no.4
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• pp.1-9
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• 2003

To reduce the possibility of longitudinal dynamic instability, called "POGO", in the liquid rocket system due to the feedback effect of a main structure and a fuel-feeding system, several different types of PSD(POGO Suppression Device) systems have been studied. In the present study, several different types of PSD were reviewed. Basically, all PSD systems can be categorized into two groups; a passive PSD or an active PSD. We can classify the passive PSD's into more detailed groups according to their compliance methods; localized compliance methods or distributed compliance methods. As a result of our intensive review on various PSD's, the gas-filled accumulator with a level control system is considered to be the most suitable one to suppress the POGO instability without mal-effects to the performance of a fuel-feeding system.ng system.

• The korean journal of orthodontics
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• v.34 no.5 s.106
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• pp.458-464
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• 2004

Anchorage plays an important role in orthodontic treatment especially in the maxillary arch. In spite of many efforts for anchorage control. it was difficult for clinicians to predict the result of treatment because most of the treatment necessitated an absolute compliance of patients, But recently, skeletal anchorage has been used widely because it does not necessitate patient compliance but produces absolute anchorage. In addition titanium miniscrews have several advantages such as ease of insertion and removal. possible immediate leading and use in limited implantation spaces. In this case, a skeletal Class I bialveolar protrusion Patient was treated with standard edgewise mechanics using indirect active P.S.A. (palatal skeletal anchorage). The miniscrews in the paramedian area of the hard palate provided anchorage for retraction of the upper anterior teeth and remained firm and stable throughout treatment This indicates that the PSA can be used to reinforce anchorage for orthodontic treatment in the maxillary arch Consequently, this new approach can help effective tooth movement without patient compliance, when used with various transpalatal arch systems.

• Tuberculosis and Respiratory Diseases
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• v.81 no.1
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• pp.6-12
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• 2018

The role of the treatment for latent tuberculosis infection (LTBI) has been underscored in the intermediate tuberculosis (TB) burden countries like South Korea. LTBI treatment is recommended only for patients at risk for progression to active TB-those with frequent exposure to active TB cases, and those with clinical risk factors (e.g., immunocompromised patients). Recently revised National Institute for Health and Care Excellence (NICE) guideline recommended that close contacts of individuals with active pulmonary or laryngeal TB, aged between 18 and 65 years, should undergo LTBI treatment. Various regimens for LTBI treatment were recommended in NICE, World Health Organization (WHO), and Centers for Disease Control and Prevention guidelines, and superiority of one recommended regimen over another was not yet established. Traditional 6 to 9 months of isoniazid (6H or 9H) regimen has an advantage of the most abundant evidence for clinical efficacy-60%-90% of estimated protective effect. However, 6H or 9H regimen is related with hepatotoxicity and low compliance. Four months of rifampin regimen is characterized by less hepatotoxicity and better compliance than 9H, but has few evidence of clinical efficacy. Three months of isoniazid plus rifampin was proved equivalence with 6H or 9H regimen in terms of efficacy and safety, which was recommended in NICE and WHO guidelines. The clinical efficacy of isoniazid plus rifapentine once-weekly regimen for 3 months was demonstrated recently, which is not yet introduced into South Korea.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.74.6-74
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• 2002

$\textbullet$ A new implant capable of controlling IOP actively and coping with personal difference among patients $\textbullet$ The valve actuator of the active implant is proposed and fabricated. $\textbullet$ In vitro experiments are carried out extensively with and without a rabbit. $\textbullet$ The experiments are conducted by using the open and closed loop pressure control. $\textbullet$ The experiment with the rabbit is similar as a in vivo experiment, $\textbullet$ since the compliance and the aqueous humor of the rabbit's eye are included. $\textbullet$ The experimental results verify the possibility of the valve actuator for a glaucoma implant.

• The Journal of Korea Robotics Society
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• v.14 no.2
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• pp.131-138
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• 2019

In this study, we developed an FSEA(Force-sensing Series Elastic Actuator) composed of a spring and an actuator has been developed to compensate for external disturbance forced. The FSEA has a simple structure in which the spring and the actuator are connected in series, and the external force can be easily measured through the displacement of the spring. And the characteristic of the spring absorbs the shock to the small disturbance and increases the sense of stability. It is designed and constructed to control the stiffness of such springs more flexibly according to the situation. The conventional FSEA uses a fixed stiffness spring and the actuator is not compensated properly when it receives large or small external force. Through this experiment, it is confirmed that FSEA compensates the external force through the proposed algorithm that the variable stiffness compensates well for large and small external forces.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.5
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• pp.421-426
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• 2015

Need to develop human body's posture supervised robots, gave the push to researchers to think over dexterous design of exoskeleton robots. It requires to develop quantitative techniques to assess human motor function and generate the command to assist in compliance with complex human motion. Upper limb rehabilitation robots, are one of those robots. These robots are used for the rehabilitation of patients having movement disorder due to spinal or brain injuries. One aspect that must be fulfilled by these robots, is to cope with uncertainties due to different patients, without significantly degrading the performance. In this paper, we propose chattering free sliding mode control technique for this purpose. This control technique is not only able to handle matched uncertainties due to different patients but also for unmatched as well. Using this technique, patients feel active assistance as they deviate from the desired trajectory. Proposed methodology is implemented on seven degrees of freedom (DOF) upper limb rehabilitation robot. In this robot, shoulder and elbow joints are powered by electric motors while rest of the joints are kept passive. Due to these active joints, robot is able to move in sagittal plane only while abduction and adduction motion in shoulder joint is kept passive. Exoskeleton performance is evaluated experimentally by a neurologically intact subjects while varying the mass properties. Results show effectiveness of proposed control methodology for the given scenario even having 20 % uncertain parameters in system modeling.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7725-7730
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• 2013

Objective: The purpose of this study was to evaluate secondhand smoke (SHS) exposure inside selected public places to provide basic data for the development and promotion of smoke-free policies. Methods: Between March and May 2009, an SHS exposure survey was conducted. $PM_{2.5}$ levels and air nicotine concentrations were measured in hospitals (n=5), government buildings (4), restaurants (10) and entertainment venues (10) in Seoul, Republic of Korea, using a common protocol. Field researchers completed an observational questionnaire to document evidence of active smoking (the smell of cigarette smoke, presence of cigarette butts and witnessing people smoking) and administered a questionnaire regarding building characteristics and smoking policy. Results: Indoor $PM_{2.5}$ levels and air nicotine concentrations were relatively higher in monitoring sites where smoking is not prohibited by law. Entertainment venues had the highest values of $PM_{2.5}$(${\mu}g/m^3$) and air nicotine concentration(${\mu}g/m^3$), which were 7.6 and 67.9 fold higher than those of hospitals, respectively, where the values were the lowest. When evidence of active smoking was present, the mean $PM_{2.5}$ level was 104.9 ${\mu}g/m^3$, i.e., more than 4-fold the level determined by the World Health Organization for 24-hr exposure (25 ${\mu}g/m^3$). Mean indoor air nicotine concentration at monitoring sites with evidence of active smoking was 59-fold higher than at sites without this evidence (2.94 ${\mu}g/m^3$ vs. 0.05 ${\mu}g/m^3$). The results were similar at all specific monitoring sites except restaurants, where mean indoor $PM_{2.5}$ levels did not differ at sites with and without active smoking evidence and indoor air nicotine concentrations were higher in sites without evidence of smoking. Conclusion: Nicotine was detected in most of our monitoring sites, including those where smoking is prohibited by law, such as hospitals, demonstrating that enforcement and compliance with current smoke-free policies in Korea is not adequate to protect against SHS exposure.