• 한국기계연구소 소보
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• s.20
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• pp.5-11
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• 1990

Most water cannon machines use compressed gas to accelerate a piston which extrudes water through a cumulation nozzle. Very high jet stagnation-pressures can be achieved by using a specially-shaped nozzle which is initially filled with air or vacuum. The objective of this study was to establish the basic technology of water cannon using exponential type nozzle. An experimental water cannon including high pressure components such as exponential nozzle and 300atm air resrvior were designed and tested. Parameters that influence the performance of the system and jet characteristics were examined.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.5
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• pp.554-562
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• 2015

This paper describes an analysis of an architecture and control system of a firefighting cannon manipulator (FCM) composed of two joint axes and one water-shooting actuator. Because the orienting FCM motion is disturbed by the reaction force from water shooting, the water shooting force has been modeled for robust control. The dynamics model of the manipulator has been set up including the external force of water-shooting reaction on the manipulator. A PD Controller and Sliding Mode Controller have been designed and their performance been tested through simulation to track a desired trajectory under the disturbance of a water-shooting reaction. The simulation shows that the performance of the Sliding Mode Controller is better than that of the PD controller.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.3
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• pp.155-161
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• 2013

To reduce the personnel and material loss caused by fire, we propose the automatic fire extinguishing system based on the ignition point tracking using the flame detecter. This automatic fire extinguishing system is composed of the flame detecting system and the fire extinguishing system based on the water cannon. We study the method for the ignition point tracking and the automatic fire extinguishing using the water cannon and the flame detecter. The flame detecting system for the early fire detection and the ignition point tracking has to be satisfied the requirement of the detecting range and the flame detection time. So we study the signal process algorithm for an improvement of the flame detecting system.

• Korean Security Journal
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• no.50
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• pp.307-337
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• 2017

The freedom of assembly is the fundamental freedoms guaranteed by the Constitution. However, as far as our reality is concerned, the freedom of assembly is guaranteed only when it is under the control of the police, and otherwise it is perceived as an object to be suppressed. Police say even that they will not tolerate even a small illegal law while referring to the "broken window theory". Therefore, regardless of the peaceful nature of the rally, it is too obsessed with 'compliance'. This attitude is causing the citizens who participated in the assembly to be put to the object to be suppressed. This paper analyzes the requirements and current status of police force, focusing on the vehicle-wall-blocking and water cannon as a means of using the police force, which is a recent problem, and suggests ways to improve it. First of all, the installation of the wall cuts off the essential communication function of the assembly by separating the meeting place from the object of protest. Thus, despite the warning for prevention in the face of illegal acts, other than installing a barrier, it should be allowed only in the 'urgent case where there is a risk of causing damage to the life, body or property of the person'. Without this urgency, the vehicle-wall-blocking should not be allowed to be proactive as well as preventive. Secondly, the water cannon is a police force that is likely to harm people's life and body. Therefore, aiming shots, which could pose a significant risk to the human body, should in principle be prohibited. However, considering its risk, it should be supplementary used only when there is no other alternative, only when the direct risk to the legal interest of the other person or the order of public well-being is 'obvious'. In addition, as for the use standard of such a thing, it is necessary to be specified by law.

• Fire Science and Engineering
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• v.33 no.1
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• pp.92-98
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• 2019

To determine if water-jet nozzle moves and water jetting are effective according to the location of the fire, this study examined the automatic fire-tracking water cannon system and aan indoor hydrant system, such as water jet centered directivity, water jet range maintainability and water jet shape uniformity. First, an examination to find the center of fire accurately from this system design showed that the water jet centered test was accurate. Second, the water jet range test results showed that when water is jetted at the maximum water jet radius, the water jet shows an inaccurate result but within the allowable tolerance range. Finally, the water-jet shape test result confirmed that there are no problems in setting the block from the algorithm design.

• Fire Science and Engineering
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• v.10 no.4
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• pp.37-42
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• 1996

The "Intelligent Fire detecting and Extinguishing System" is an up-to-date fire protection system for modern high-rise buildings, international airports, enormous industrial facilities, dome stadiums such as specific areas in which the application of our local fire protection regulation could not be satisfied. The state-of-the art initiating devices communicated with sophisticated network control panels enable peoples to get reliable and powerful suppressions using water or gas, providing absolute protection. The Intelligent Water Cannon System, the Low Pressure $CO_2$ System and the MXL Networking Fire Alarm System introduced in this paper accomplish the dynamic protection for the special hazards.

• Bulletin of the Korean Chemical Society
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• v.6 no.2
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• pp.115-118
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• 1985

The oxidation of hydrazobenzene by oxygen in methanol solution is catalysed by Co(3MeOsalen) which is a synthetic oxygen carrier. The products are trans-azobenzene and water. The rate of the reaction has been studied spectrophotometrically and the rate law established. A mechanism involving a ternary complex of catalyst, hydrazobenzene and oxygen has been proposed.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.5
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• pp.907-913
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• 2023

Currently, the sprinkler method is widely used as an initial suppression method in existing firefighting systems. However, this method can cause significant damage to both equipment and facilities in the hydration area. To minimize this damage, fire extinguishing monitors are being developed that can spray fire extinguishing water directly at the point of fire. These monitors are installed on the top floor of the ship, such as the Living Quarter and Ventilation System. While conventional fire extinguishing monitors focus on lightweight research with a short spray port and require a spray distance of about 40 to 45m, recent developments necessitate a longer spray port, similar to a water cannon, requiring a spray distance of about 70 to 75m. This study aims to predict the injection distance of both the existing ship-installed fire extinguisher and the long spray port fire extinguisher through hydrodynamic computer analysis, and to determine whether the injection distance has increased.

• Bulletin of the Korean Chemical Society
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• v.27 no.2
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• pp.255-265
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• 2006

The oxidation of hydrazobenzene by molecular oxygen in the polar solvent methanol is catalysed by a Schiff's base complex Co(3MeOsalen) which is a synthetic oxygen carrier. The products are trans-azobenzene and water. The rate of the reaction has been studied spectrophotometrically and the rate law established. A mechanism involving a ternary complex of catalyst, hydrazobenzene and molecular oxygen has been proposed. The kinetic studies show that a ternary complex $CoL{\cdot}H_2AB{\cdot}O_2$ is involved in the rate determining step. The reactions are summarised in a catalytic cycle. The kinetic data suggest that a ternary complex involving Co(3MeOsalen), triphenyl-phosphine and molecular oxygen is catalytically acive species but at higher triphenylphosphine concentrations the catalyst becomes inactive. The destruction of the catalytic activity could be due to the catalyst becoming coordinated with triphenyl phosphine at both z axis sites of the complex e.g. Co (3MeOsalen)$(PPh_3)_2$.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.642-649
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• 2014

Mallard (Anas platyrhynchos) is the abundant winter visitor in South Korea. Mallard migrates long distances between Russian Siberia and Korea. This species prefers a rice paddy area as their winter habitat. We captured birds using cannon-net, and attached the GPS-Mobile phone based Telemetry(WT-200) on Seven Mallards in the winter of 2011~2013. We were monitored wintering home-range and movement distance. We analyzed the tracking location data using ArcGIS 9.0 and calculated Kernel Density Estimation (KDE) and Minimum Convex Polygon (MCP). The average home-range in the wintering ground by MCP was $118.8km^2$(SD=70.1, n=7)and the maximum home-rang was $221.8km^2$ and the minimum was $27.7km^2$. Extents of home-range by KDE were $60.0km^2$(KDE 90%), $23.0km^2$(KDE 70%) and $11.6km^2$(KDE 50%). Mallard moved an average of 19.4 km from start site(attach to WT-200 site), maximum moved was 33.2 km and minimum moved was 9.4 km. The average distance of 0.8 km between GPS fixed point(range 0.2~1.6 km), maximum moved was 19.7 km. Mallard moved a very short distance in wintering season and showed a very high water-dependent trends in wintering site.