• Korean Journal of Construction Engineering and Management
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• v.9 no.3
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• pp.175-184
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• 2008

As defined by the experts, safety education is the basic method through which people can protect themselves from the dangers in workplace. Therefore, safety education is an important safety measure that can be effectively utilized in disaster prevention without any certain limit. The current practice of safety education in construction sites, however, is all formal and has no substance. Safety education became a mere boring time to workers since the material is not related to them, and does not reflect the individual personalities, which cannot induce voluntary participation of workers. Thus, it is vital to develop various safety education models suitable for individual personalities of construction workers. This study aims to provide the basic data necessary to establish safety education models according to individual personalities of construction workers. Based on the analysis of the preliminary stuff and interviews, the typical individual personalities of construction workers and safety education factors were examined, and the frameworks for each were established. Based on results of applying them to actual cases, directions to improve safety education in construction sites are presented.

• Journal of the Korean Society of Safety
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• v.38 no.3
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• pp.10-19
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• 2023

Fall accidents account for the highest accident fatality rate in the construction industry. In addition, wearing and using a safety belt is the most realistic and important preventive measure to reduce fall accidents. Safety belts are protective devices worn by individual workers; they prevent workers from falling and allow for time to rescue the workers. However, the legal standards for safety belts only stipulate the materials, specifications, and strength of parts; there is no provision for an auxiliary rope fixing method to fix the safety belts safely. Due to this reason, workers in industrial sites arbitrarily fix and use the auxiliary rope. Currently, the most used method to fix the auxiliary rope is to tie a knot, which significantly lowers the strength of the material compared to the standard strength. Moreover, many construction sites are located outdoors, so the strength of the materials used in the auxiliary rope is inevitably reduced due to various external environmental conditions. Therefore, to solve this problem, this study was conducted to evaluate the strength of the material of the auxiliary rope for fixing the safety belt and the knot-tying method for the auxiliary rope. In this study, the exposure conditions for the effects of temperature and moisture were set to reflect the characteristics of the construction industry. The results of this study are expected to be used for standards establishment and the safe use of the auxiliary rope for safety belts in actual field applications.

• Journal of Ship and Ocean Technology
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• v.11 no.1
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• pp.36-46
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• 2007

The maintenance of a ship is essential for safe navigation and hence regular surveys are prescribed according to the rule of classification societies. A hull inspection is generally performed by professional divers, but it takes a long time and the efficiency is low in terms of time and cost. In this research, a ROV(Remotely Operated Vehicle) named as SNU-ROV(Seoul National University-ROV) is developed to replace the conventional inspection method. In this system, the ROV is intended to be used for inspecting ship and harbor because harbor inspection is merging as a safety measure against any possible terror actions. In order to increase the efficiency of inspection, the ROV must be able to measure the exact position of damages. SNU-ROV has a positioning system based on LBL(Long Base Line). In shallow water such as harbor, however, LBL has bad DOP(Dilution of Precision) in the depth direction due to the limited depth. Thus LBL only can not locate the exact depth position. To solve the DOP problem, a pressure sensor is introduced to LBL and a complementary filter is attached by using indirect feedback Kalman filter. Thus developed positioning system is verified by simulation and experiment in towing tank.

• Journal of Drive and Control
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• v.18 no.1
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• pp.9-16
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• 2021

Overloaded vehicles increase the maintenance cost of road structures, and they are a major factor in causing damage to the roads and bridges. In addition, overloaded vehicles compromise the braking capability of the vehicle; thus, threatening the safety of the driver. In order to prevent overloading of vehicles, the government is cracking down on the roads by using a device that measures the weight of vehicles. But this process is inconvenient because the place where the equipment is installed is far away from where the cargo is loaded. Due to the limitations of these fixed weighing devices, there is a growing need for technology that can monitor vehicle weight distribution and overload conditions in real time. In this work, we develop an onboard scale that can measure the load (weight) of trucks in real time. The onboard scale consists of high sensors, a signal processing unit, and a display, and it measures the load using height-displacement of the vehicle's leaf spring suspension.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.9
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• pp.891-897
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• 2010

This paper proposes a cooperative control algorithm for a dual-arms robot which is carrying an object to the desired location. When the dual-arms robot is carrying an object from the start to the goal point, the optimal path in terms of safety, energy, and time needs to be selected among the numerous possible paths. In order to quantify the carrying efficiency of dual-arms, DAMM (Dual Arm Manipulability Measure) has been defined and applied for the decision of the optimal path. The DAMM is defined as the intersection of the manipulability ellipsoids of the dual-arms, while the manipulability measure indicates a relationship between the joint velocity and the Cartesian velocity for each arm. The cost function for achieving the optimal path is defined as the summation of the distance to the goal and inverse of this DAMM, which aims to generate the efficient motion to the goal. It is confirmed that the optimal path planning keeps higher manipulability through the short distance path by using computer simulation. To show the effectiveness of this cooperative control algorithm experimentally, a 5-DOF dual-arm robot with distributed controllers for synchronization control has been developed and used for the experiments.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.705-711
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• 2022

Roadway lighting is an integral element of a highway system. Luminaires on roadways provide viewing conditions for drivers and pedestrians during nighttime in order to improve safety. It is time-consuming and labor-intensive to manually measure roadway illuminance at predetermined spots with a handheld illuminance meter. To improve the efficiency of illuminance measurement, a remote-control electrical cart and a drone were utilized to carry an illuminance meter for the measurements. The measurements were performed on the marked grid points along the pavement. To measure the illuminance manually, one person measures illuminance at each grid point with the handheld meter and another person records the illuminance value. To measure the illuminance with the remote-control cart, the illuminance meter is attached to the cart and it measures illuminance values continuously as the cart moves along the grid lines. With the drone, the meter records the illuminance continuously as the drone carries the meter and flies along the grid line. Because the drone can fly at different heights, the measurements can be done at different altitudes. The illuminance measurements using the cart and the drone are described in detail and compared with manual measurements in this paper. It is shown through this study that automated measurements can greatly improve the efficiency of roadway illuminance data measurements.

• Journal of the Korean Society of Safety
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• v.25 no.5
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• pp.27-32
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• 2010

This study is to investigate and compare domestic hazardous toys with harmful substances with foreign toys so that we can find out management criteria for in cognitive infants. Actually, commercially used toys have been collected and tested to find out more effective management standard. it is tried to produce evaluation criteria of environmentally harmful substance but variety of product is needed for overcoming actual barrier due to lot of difficulty huge cost, time, objectiveness. Therefore, This study does not cover all the above. Establishment of evaluation criteria for product harmfulness made by Government or Local government should be continued to improve. Foreign reference material for toy product in Europe, USA, Japan have been investigated and domestic product have been collected and tested for containing heavy metals, formaldehyde, phthalate in the study. All the test have been made in accordance with KSM ISO 2124 to measure heavy metal transfer into body. Toy product used for the study have been purchased in the real market and some of them contains harmful elements with over standard. Post management system such as RAPEX to control periodically should be established for plastic toy with low quality product.

• Safety and Health at Work
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• v.7 no.3
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• pp.185-193
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• 2016

Background: Management and workers in small and medium-sized enterprises (SMEs) often find it hard to comprehend the requirements related to controlling risks due to exposure to substances. An intervention study was set up in order to support 45 SMEs in improving the management of the risks of occupational exposure to chemicals, and in using the control banding tool and exposure model Stoffenmanager in this process. Methods: A 2-year intervention study was carried out, in which a mix of individual and collective training and support was offered, and baseline and effect measurements were carried out by means of structured interviews, in order to measure progress made. A seven-phase implementation evolutionary ladder was used for this purpose. Success and failure factors were identified by means of company visits and structured interviews. Results: Most companies clearly moved upwards on the implementation evolutionary ladder; 76% of the companies by at least one phase, and 62% by at least two phases. Success and failure factors were described. Conclusion: Active training and coaching helped the participating companies to improve their chemical risk management, and to avoid making mistakes when using and applying Stoffenmanager. The use of validated tools embedded in a community platform appears to support companies to organize and structure their chemical risk management in a business-wise manner, but much depends upon motivated occupational health and safety (OHS) professionals, management support, and willingness to invest time and means.

• Journal of the Korean Society of Safety
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• v.29 no.3
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• pp.20-27
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• 2014

Cooling equipment is the frequent occurrence of fire despite the absence of the heating element. National fire statistics in 2013 show that a total of 263 fires occurred in the cooling equipment and the number of electric fan has 145 fire cases. This is accounted for 55.1% of the whole. Electric fan is the electrical appliance that the heat is generated on the winding wire and the iron core. If such characteristic is not controled properly, fire would break out at the electric fan. also there is a gap filled with an insulator between connection terminals of the capacitor in the electric fan. But in case that the gap on the capacitor is covered with some conductive material such as dust, there would be a fire as well caused by electrical heating locally. Although many studies related with those have been conducted, electric fan fire is continuously occurred. In this study, thermal characteristics and current signal in various conditions such as the heat generation of windings including iron cores of the motor and the dielectric breakdown of terminals on the capacitor connected to the motor were detected. In order to measure the maximum temperature, "third level" wind velocity button was pushed and the time selection switch to "continuation" was set. Analyzed data would be available for the fire safety of the electric fan.

• Journal of the Korea Safety Management & Science
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• v.17 no.2
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• pp.229-234
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• 2015

Depending on the living styles, the types of energy consumed by households have changed, and the consumption has increased rapidly. Consequently, those have led to environmental issues, such as exhaustion of energy and the climate changes. As one of solutions to such issues, energy efficiency can be approached. Therefore, in this study, the gas water heater(115S type Rheem products) that made in Germany and obtain hot water using gas as a heat source is selected. a $1.0m^3$ water tank with a 6kW electronic heater is installed and a water temperature and pressure is maintain constantly also thermometer is injected. Two of gas meter, one of pressure regulator and three of time measurement devices are installed in a combustion facility and fuelling facility with a magnet valve so it can observe and record combustion reactions. Quantity of hot water that heated by boiler is recorded using a quantity measurement tank, and have been heated by the boiler have been to record and measure the amount and utilized the data acquired through measurement of all factors that are applied to acquire hot water in order to calculate the use rate of final energy. In conclusion, this researcher drew the economic strong points of the hot water generated by gas.