• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.817-832
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• 2021

In this paper, a simple practical method to estimate the drag of Super-Cavitating Underwater Vehicles (SCUV) is proposed that can obtain the drag with only principal dimensions in an initial design stage. SCUV is divided into cavitator, forebody, afterbody, base, and control fin and the drag of each part is estimated. The formulas for the drag coefficient are proposed for the disk and cone type cavitators and wedges used as control fins. The formulas are a function of cavitation number, cone or wedge angle, and Reynolds number. This method can confirm the drag characteristics of SCUV that the drag hump appears according to the coverage of the body by the cavity and the cavitator drag remains only when the entire body is covered by cavity. Applying this method to SCUV of various shapes, it is confirmed that the effects of cavitating and non-cavitating conditions, cavitator and body shape, and speed could be found.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.1
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• pp.55-66
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• 2018

Judicious control of high temperature is the most important task for the successful intensive-cultivation of vegetables in glasshouses during the hot summer. Estimation of cooling load and wise selection of suitable equipments and facilities based upon the environmental conditions are essential for the efficient temperature control. A series of experiments were carried out to investigate VETH(ventilation, evapotranspiration, temperature and humidity) plot was prepared for the possible practical application in designing some evaporated cooling methods for the following 9 locations; Seoul, Seosan, Taejeon, Pusan, Cheju, Kwangju, Taegu, Chonju, and Chinju.

• Journal of muscle and joint health
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• v.25 no.2
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• pp.135-147
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• 2018

Purpose: The purpose of this study was to develop evidence-based guidelines for infection control in nursing homes in Korea (ENIK). Methods: Three steps were planned for the development which were developing a draft and testing the content validity. First, the draft was based on evidence and developed through focus group interviews with nurses in nursing homes, a comprehensive review of international guidelines and literature, and systematic reviews of interventions for infection control and outbreaks in long-term care facilities. Clinical applicability was established through reviews of nursing records and job assignments in one nursing home. The final step consisted of experts evaluating the content validity. The ENIK was revised to fit Korean nursing homes. Results: The ENIK consisted of recommendations in 9 compositions and a one-page practical algorithm. The principles of infection control were presented by statements and specific strategies were recommended in resident care programs. The infection control practical algorithm was organized into 3 steps: screening at admission, prevention, and control at the early stage. The practice to control infection was composed of a 5-step process. Conclusion: The ENIK will contribute to improving the competency of infection control practice because it provides standardized practice and is tailored to Korean nursing homes.

• Convergence Security Journal
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• v.24 no.2
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• pp.39-45
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• 2024

The purpose of security control in the public sector is to secure the safety of administrative services for the public by preventing resource loss or information infringement in information systems and information and communication networks. The security control system is a process that performs real-time detection, analysis, response, and reporting through system vulnerability analysis and security system detection pattern optimization. This study aims to objectively identify the current situation of the mismatch between the supply and demand of cyber security control centers currently in operation and specialized security control companies that can be entrusted to operate them, and to derive and propose practical and institutional improvement measures. Considering that the operation of security control centers in the public sector is expected to increase in the future, research on the practical supplementation required for the operation process of security control centers and the improvement of the designation system of security control specialized organizations has fundamental and timely significance, and it is an area that requires continuous research in terms of strategic industrialization.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.153-158
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• 2004

In this paper, we proposed a two-stage control of the container crane. The first stage control is time-optimal control for the purpose of fast trolley traveling. With suitable trolley velocity patterns, the sway which is generated during trolley moving is minimized. At the second stage control feedback control law is investigated for the quick suppression of residual vibration after the trolley motion. For more practical system, the container crane system is modeled as a partial differential equation (PDE) system with flexible cable. The dynamics of the cable is derived as a moving system with tension caused by payload using Hamilton's principle for the systems. A control law based upon the Lyapunov's method is derived. It is revealed that a time-varying control force and a suitable passive damping at the actuator can successfully suppress the transverse vibrations.

• 한국ITS학회:학술대회논문집
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• 2008.11a
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• pp.158-160
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• 2008

• Journal of Power Electronics
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• v.7 no.1
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• pp.1-12
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• 2007

Novel nonlinear backstepping control with integrated adaptive control function is developed for high-performance positioning control systems. The proposed schemes are synthesized by a systematic approach and implemented based on a modern low-cost DSP controller, TMS320C32. A baseline backstepping control scheme is derived first, and is then extended to include a nonlinear adaptive control against the system parameter changes and load variations. The backstepping control utilizes Lyapunov function to guarantee the convergence of the position tracking error. The final control algorithm is a convenient in the implementation of a practical 32-bit DSP controller. The new control system can achieve superior performance over the conventional nested PI controllers, with improved position tracking, control bandwidth, and robustness against external disturbances, which is demonstrated by experimental results.

• The Journal of the Korean dental association
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• v.51 no.3
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• pp.130-137
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• 2013

Infection control is critical to good dental practice. To this end, it is essential that the practitioner not only understand the concepts involved in the development and applications of antimicrobial(physical and chemical) agents but also know how to use them properly in the dental operatory. Practical applications of infection control are more fully described in several of the suggested references.

• Journal of Industrial Technology
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• v.28 no.A
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• pp.149-153
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• 2008

$C_p$ and other process capability indices are used extensively in industry, However, They are inadequate and widely misused. In a practical application, process average ${\mu}$ is almost always drifted by various assignable causes in process. And control charts will not detect these shifts in process average. In this study, incorporating these undetected shifts, a new capability analysis method is introduced.

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.280-284
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• 1997

In this paper theoretical foundation of distribution STATCON, the operating characteristics of D-STATCON, the overview of control technologies for power factor correction of D-STATCON, and the PWM current control of D-STATCON and simulated results are given to shows the practical feasibility of a Flexible AC Transmission System and Distribution Static Condenser.