• Journal of fish pathology
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• v.33 no.1
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• pp.97-101
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• 2020

Although aquaculture production rates grown over the years, aquatic animal diseases occur every year which causes substantial economic losses. When an aquatic animal is infected with an aquatic animal pathogen it is either incinerated or buried according to the aquatic life disease control act. Although these methods prevent the spread of disease, it is not environment friendly. Here, we developed an aquatic animal rendering equipment for disposal of fish waste which is environment-friendly and efficient. Also, fertilizer components of fish waste were evaluated value for recycling. The mobile rendering equipment was designed for field operation and/or high temperature and pressure system, oil and water separator, and shredding drying apparatus. During the experiment (July-2016 to November-2016), a total of 53,824 kg fish waste was collected, and 29,216 kg compost of rendering by-product was made. Also, compost made from viral (Viral hemorrhagic septicemia virus) infected fish did not reflect any detectable pathogen. The concentration of nitrogen, phosphorus, and organic matter in the fish waste compost were 2.17%, 26.98%, and 92.44%, respectively. The results suggest that fish waste used in this study was decomposed efficiently as per the official standard for fertilizer product. This equipment can be useful for efficient inactivation of the aquatic animal pathogenic agents and recycling of the fish waste in an environment-friendly manner.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.7
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• pp.683-689
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• 2017

We have carried out the development for hydraulic breaker which can be operated by optimal mode with ICT convergence technology. This developed system can predict the rock properties. Moreover, this system can maximize the energy efficient with intelligent control of hydraulic system. In order to provide the optimal impact force, this system can measure the descending depth of piston with the proximity sensor and discriminate the rock properties with the measuring data and control the piston stroke using solenoid valve eventually. In addition, we have developed the controller, display module and operating device for cascade (multi-level impact) system and applied the module which can communicate each system by wireless communications. In conclusion, the control system which can control the multi-level impact in accordance with strength of rocks has been developed and approved by several field tests.

• The Journal of Korean Academic Society of Nursing Education
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• v.18 no.2
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• pp.293-302
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• 2012

Purpose: The purpose of this study was to investigate nursing students' awareness and performance on standard precautions and to provide meaningful information for nursing students' education regarding hospital infection control. Method: Four hundred forty seven nursing students at 6 universities in D-city participated in this study. Data collection was conducted from March to April 2011. Students' awareness and performance on standard precautions of infection control in hospitals were measured using the modified 2007 CDC standard precautions guidelines. Data analysis was performed using the SPSS WIN 18.0 program, descriptive statistics, t-test, and ANOVA. Results: The level of students' awareness in the standard precautions was higher than performance. The higher levels of students' awareness and performance on standard precautions included patient care equipment, safe injection practices, and worker safety. The lower levels of students' awareness and performance on standard precautions included hand hygiene and personal protective equipment. There was no difference in the students' awareness and performance of standard precautions according to their characteristics. Conclusions: Based on the findings of this study, hand hygiene and personal protective equipment need to be stressed more within the program to improve nursing students' infection control techniques.

• Journal of Power Electronics
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• v.10 no.2
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• pp.132-137
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• 2010

Interleaving techniques are widely used to reduce input/output ripples and to increase the power capacity of boost converters operating in critical conduction mode. Two types of phase-shift control schemes are studied in this paper, the turn-on time shifting method and the turn-off time shifting method. It is found that although the turn-off time shifting method exhibits better performance, it suffers from sub-harmonic oscillations at high input voltages. To solve this problem, an intensive quantitative analysis of the sub-harmonic oscillation phenomenon is made in this paper. Based upon that, a novel modified turn off time shifting control scheme for interleaved boost converters operating in critical conduction mode is proposed. An important advantage of this scheme is that both the master phase and the slave phase can operate stably in critical conduction mode without any oscillations in the full input voltage range. This method is implemented with a FPGA based digital PWM control platform, and tests were carried out on a two-phase interleaved boost PFC converter prototype. Experimental results demonstrated the feasibility and performance of the proposed phase-shift control scheme.

• Journal of Power Electronics
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• v.15 no.4
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• pp.994-1005
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• 2015

This paper presents a novel power control strategy for PWM current-source rectifiers (CSRs) in the stationary frame based on the instantaneous power theory. In the proposed control strategy, a virtual resistance based on the capacitor voltage feedback is used to realize the active damping. In addition, the proportional resonant (PR) controller under the two-phase stationary coordinate is designed to track the ac reference current and to avoid the strong coupling brought about by the coordinate transformation. The limitations on improving steady-state performance of the PR controller is investigated and mitigated using a cascaded lead-lag compensator. In the z-domain, a straightforward procedure is developed to analyze and design the control-loop with the help of MATLAB/SISO software tools. In addition, robustness against parameter variations is analyzed. Finally, simulation and experimental results verify the proposed control scheme and design method.

• Science of Emotion and Sensibility
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• v.15 no.2
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• pp.269-282
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• 2012

Laboratory equipment will continue to be developed and created as long as experiments continue. Up until now, the designs have been focused on the functional role; successfully process the study purpose. However, nowadays, the requirements of providing emotional satisfaction of the design, has increased. Even so, the users are normally limited by specific groups and investments on these designs have been neglected due to small annual production by the small market. Through this study, we have conducted an emotional evaluation on Temperature and Humidity Chamber's (TH Chamber) exterior shape. First of all, we extracted emotional words and placed them in categories that represent these emotions and conducted an emotional evaluation on four typical TH chamber models. They were selected based on its door lock type and control box type. The result showed that the 'fixed type' of control box and the 'handle type' of door lock were most favorable by the users, satisfying the five representative emotions; 'Attractiveness', 'Classiness', 'Comfortableness', 'Pleasant' and 'Satisfaction in Usability'. Particularly, all 4 emotional words in the 'Satisfaction in Usability' category recorded over 3.65. This indicates that Satisfaction in Usability is relatively an important category when expressing laboratory equipment. The result of this research is expected to be used as a basic data to find a way of right approach in laboratory equipment design.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2226-2230
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• 2005

The Advanced Spent Fuel Conditioning Process (ACP), which is a pre-disposal treatment process for spent fuel is being developed at the Korea Atomic Energy Research Institute (KAERI). The ACP equipment is operated in an intense radiation field as well as in a high temperature. Thus, the equipment is designed in consideration of the remote handling and maintenance. This paper describes a Bridge Transported Bilateral Force-Reflecting Servo-Manipulator (BTSM) system, which is being developed to overcome the limitation of access that is a drawback of the mechanical Master-Slave Manipulators (MSMs), which are mounted on the ACP hot cell wall for the operation and the maintenance of the ACP equipment. The BTSM system was manufactured and temporally installed at the mockup to test its performance. The manufactured BTSM system will be installed at the ACP hot cell on June 2005 after the accomplishment of the performance test. The BTSM system consists of four components: a transporter with a telescoping tubeset, a slave manipulator, a master manipulator, and a remote control system. This system will highly increase the volume of coverage for the operation and maintenance of the ACP equipment.

• International Journal of Safety
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• v.9 no.2
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• pp.35-40
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• 2010

Many casualties are being occurred due to many misses the railway platform, and the accident occurrence is being increased. Recently in Korea, efforts to prevent casualties fundamentally are being made by installing and operating the PSD(Passenger Screen Door) as to prevent these casualties of passengers. However, in case of the PSD system, although it can solve the problem of public casualties at platform fundamentally, it is impossible to install it at whole railway platforms. This paper proposes the safety equipment using LaserRadar sensor for the prevention against casualties of passengers at platform. The safety equipment using novel sensor is the safety equipment making an approaching train stopped if the falling object is a person by detecting the obstacle at platform, and it has the merit possible to apply it to platform since it may detect accurately under ambient environmental elements such as the snow, rain and yellow dust, etc. also. We manufactured a prototype of the safety equipment to reduce public casualties at platform by using LaserRadar sensor and carried out its performance test, and the result is presented in this paper.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.3 no.2
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• pp.31-37
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• 2007

The fuzzy control algorithm for HVAC system has been developed for minimizing energy consumption while maintaining the comfort of indoor thermal environment in terms of the environmental variables such as time varying indoor cooling load and outdoor temperatures. The optimal set-points of control parameters with fuzzy control are supply air temperature, chilled water temperature and condenser temperature. This study has been done by using TRNSYS program in order to analyze the HVAC system response. As a result, the fuzzy control algorithm with PID algorithm shows good energy performance in comparison with conventional one.

• Proceedings of the Korean Reliability Society Conference
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• 2000.04a
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• pp.231-238
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• 2000

The distributed digital control system has many shared common components, and a single fault in the system may have effects on not a single function. Not as in an analog system, the faults in a digital system usually make discrete and abrupt changes in its output, which are hard to be expected. To cope with these situations, the fault-tolerance is an inevitable property of a distributed control system. A distributed digital control system consists of many equipments, and each equipment can be implemented by many different technologies. The fault-tolerance has to be implemented depend-ing on the overall architecture and how each equipment is implemented. The paper analyzes and compares the strategies and tactics to add the fault-tolerances in a distributed digital control system, and studies how they can be combined appropriately.