• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.24 no.2
• /
• pp.103-112
• /
• 2014

Objectives: The present system of occupational safety and health law gives priority to traditional command and control regulations. However, this may give rise to problems such as the delay of standard-setting and shortages of human resources. The aim of this study is to examine the usability of private standards in occupational safety and health systems. Materials: After the limits of occupational safety and health law were examined, an application plan for private norms (EN, as enforced in the EU) and occupational safety and health management systems (OSHMS) was investigated. Results: The utilization of private norms and OSHMS may address the limits of the current legal system. In particular, OSHMS is known internationally as a measure for achieving improvements in overall occupational safety and health performance. As a result, occupational safety and health law and private norms/OSHMS are complementary to one another. Conclusions: Even though the utilization of private standards may give rise to legal questions, such standards as complementary measures to traditional command and control regulations need to be utilized progressively in occupational safety and health systems.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.31 no.10
• /
• pp.79-88
• /
• 2003

The paper presented here covers the work associated with the flight control law design, ground based and in flight simulation and handling qualities assessment of the Fly-by-Wire type Aircraft (FBWA). The FBWA configurations are of the same generic form of the Korean advanced trainer. The normal acceleration (Nz) and pitch rate (q) feedback control system is employed for longitudinal axis and roll rate (p) and lateral acceleration (Ny) feedback flight control law is developed in lateral/ directional axis. The flight tests for the FBW A dynamics evaluation were executed for the target aircraft (FBWA) on the IFS (In-Flight-Simulator) aircraft . The test results showed that Level 1 handling qualities for the most unstable flight regime and Level 1/2 for the landing approach flight regime were achieved. And the designed FBWA flight control law has revealed acceptable CHR (Cooper-Harper handling qualities Ratings).

• International Area Studies Review
• /
• v.14 no.2
• /
• pp.275-296
• /
• 2010

This study aims to identify effective ways to prevent sexually transmitted diseases among sex workers as well as the general public in Korea by examining the case of Thailand, regarded as a model internationally in reducing prevalence rate of sexually transmitted diseases, under the circumstances in which the implementation of the new anti-sex-trade law causes confusion over the existing sexually transmitted disease control program. For the purpose, the study firstly assesses the anti-sex-trade law which has engendered recent debates over the relationship between sex trade and sexually transmitted diseases, and reviews a change of the sexually transmitted disease control system made by the anti-sex-trade law. The Thai case is explored with some special emphasis on relationship between socio-cultural, political and economic factors and sexually transmitted disease control policies. Comparing to the Thai case, the study proposes some suggestions to make the existing sexually transmitted disease control program more effective under the new anti-sex-trade law.

• Journal of Institute of Control, Robotics and Systems
• /
• v.14 no.7
• /
• pp.711-719
• /
• 2008

Although non-real time simulation and pilot based evaluations are available for the development of flight control computer prior to real flight tests, there are still many risky factors. The control law designed for prototype aircraft often leads to degraded performance from the initial design objectives, therefore, the proper evaluation methods should be applied such that flight control law designed can be verified in real flight environment. The one proposed in this paper is IFS(In-Flight Simulator). Currently, this system has been implemented into the F-18 HARV(High Angle of Attack Research Vehicle), SU-27 and F-16 VISTA(Variable stability. In flight Simulation Test Aircraft) programs. This paper addresses the concept of switching mechanism for FLCC(Flight Control Computer)-SWMC(Switching Mechanism Computer) using 1553B communication based on flight control law of advanced supersonic trainer. And, the fader logic of TFS(Transient Free Switch) and stand-by mode of reset '0' type are designed to reduce abrupt transient and minimize the integrator effect in pitch axis control law. It hans been turned out from the pilot evaluation in real time that the aircraft is controllable during the inter-conversion process through the flight control computer, and level 1 handling qualities are guaranteed. In addition, flight safety is maintained with an acceptable transient response during aggressive maneuver performed in severe flight conditions.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.10
• /
• pp.1683-1693
• /
• 1997

In this paper, a new nonlinear dynamic model is derived for a 2-dimensional overhead crane based on a new definition of 2-degree-of-freedom swing angle, and a new anti-swing control law is proposed for the crane. The dynamic model and control law take simultaneous travel and traverse motions of the crane into consideration. The model is first linearized for small motions of the crane load about the vertical stable equilibrium. Then the model becomes decoupled and symmetric with respect to the travel and traverse axes of the crane. From this result, a decoupled anti-swing control law is proposed based on the linearized model via the loop shaping and root locus methods. This decoupled method guarantees not only fast damping of load-swing but also zero steady state position error with optimal transient response for the 2-dimensional motion of the crane. Finally, the proposed control method is evaluated by controlling the simultaneous travel and traverse motions of a 2-dimensional prototype overhead crane. The effectiveness of the proposed control method is then proven by the experimental results.

• Journal of Institute of Control, Robotics and Systems
• /
• v.19 no.6
• /
• pp.495-500
• /
• 2013

This paper proposes a double sliding surfaces based on a sliding mode control for a tracking control of nonholonomic mobile robots in the Cartesian coordinates. In order to remove sliding surface constraints, we design the additional sliding surface for the heading angle with respect to the newly defined coordinates. Then, we define the switching law based on the posture error to combine the designed sliding surface with the previous one. By using the double sliding surfaces and the switching law, we obtain the control law for arbitrary trajectories. It is proved that the position tracking error and the heading direction error asymptotically converge to zero, respectively, with the Lyapunov stability theory. Finally, through computer simulations, we demonstrate the effectiveness of the proposed control system.

• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.159-162
• /
• 1997

This paper describes robust stabilization of nonlinear single-input uncertain systems without matching conditions. We consider nonlinear systems with a vector of unknown constant parameters perturbed about a known value. The approach utilizes the generalized controller canonical form to lump the unmatched uncertainties recursively into the matched ones. This can be achieved via nonlinear coordinate transformations which depend not only on the states of the nonlinear system but also on the control input. Then the dynamic robust control law is derived and the stability result is also presented.

• International Journal of Control, Automation, and Systems
• /
• v.2 no.1
• /
• pp.68-75
• /
• 2004

In this paper, an estimator with an appropriate adaptive law for updating parameters is designed and analyzed based on the Lyapunov theory. The adaptive law is designed so that the estimation model follows the parameterized plant model. Using the proposed estimator, the parameters of the T-S fuzzy model can be estimated by observing the behavior of the system and it can be a basis for indirect adaptive fuzzy control.

• Proceedings of the KIEE Conference
• /
• 2003.11b
• /
• pp.15-18
• /
• 2003

This paper presents an adaptive control scheme for parking or regulating a nonholonomic mobile robot of an unicycle type with parameter uncertainty. The kinematics can be described with Brockett's nonholonomic integrator. The control law is designed in cylindrical coordinates together with the estimation law for the uncertain parameters such that the controlled signals converge to zero while guaranteeing the boundedness of the estimation errors. The effectiveness of the proposed scheme is demonstrated using simulations.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.507-507
• /
• 2000

In this paper, a kind of limit cycle of an inverted pendulum system is discussed. We propose a stabilization control law for such a limit cycle of an inverted pendulum system that the pendulum rotates periodically. Besides, the stabilization control law is extended so as to ensure not only stability of the limit cycle but also an L$_2$-gain disturbance attenuation in the presence of modeling error and viscosity friction.