• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.1
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• pp.1-8
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• 2019

In December 2017, many collision accidents of small vessels, such as those between oil refineries and fishing boats, occurred near Yeonghung-do in Incheon. In order to prevent marine casualties from small vessels, the government is striving to improve the safety capabilities of ship operators by strengthening education and improving the working environment. They are providing education and refining training regulations for fishermen operating vessels under 5 tons. However, the situation includes certain vulnerabilities. In this study, we propose a collision prevention algorithm for small vessels using the Wireless Access in Vehicular Environments (WAVE) communication system, which is a new communication technique to prevent collisions with small ships. The collision avoidance algorithm used is based on DCPA/TCPA. Research analyses, simulation experiments and questionnaires have been conducted to define the criteria of DCPA/TCPA. As a result, the standard for DCPA was $8(L_a+L_b)$ and for TCPA was 2.5 min. Three different accident cases were selected, and this algorithm was applied to confirm alarm responses at certain times. This algorithm can provide information to the operators of small ships in advance to help them recognize potential collision situations.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.2
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• pp.202-209
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• 2014

In this paper, a developed device for detecting target's location and avoiding collision is proposed. Velocity and acceleration model of target are derived to estimate target's information, i.e. position, velocity and acceleration considering process and measurement noise. Kalman filtering method applied to the estimation process and its results was confirmed by simulation. The distance measurements system using laser sensor for moving target system is also developed to confirm the effectiveness of the proposed scheme. Experiments to get information of moving target with velocity and acceleration model was executed. The data with filtering and without filtering was compared by experiments. Discontinuous measured data was changed to smooth and continuous data by Kalman filtering. It is confirmed that desired data was obtained by applying proposed scheme. UI for measuring and monitoring the target data is developed and visual and auditory alarm function is attached on the system Finally, position estimation system of moving target with good performance is achieved by low price equipments.

• Journal of Navigation and Port Research
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• v.37 no.4
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• pp.401-407
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• 2013

In parallel with the development of ship equipment, bridge systems have been improved, but marine accidents due to human error have not been reduced. Recently, research in nautical bridge equipment has focused on suitable ergonomic designs in order to reduce these errors due to human factors. In a bridge of a ship, there are numerous auditory signals that deliver important information clearly to the sailors. However, only a few studies have been conducted related to the human recognition of these auditory signals. There are three types of auditory signals: voice alarms, abstract sounds, and auditory icons. This study was conducted in order to design more appropriate auditory icons using a sensibility evaluation method. The auditory icons were rated to have five warning situations (engine failure, fire, steering failure, low power, and collision) using the Semantic Differential Method. It is expected that the results of this study will be used as basic data for auditory displays inside bridges and for integrated bridge alarm systems.

• Journal of Biomedical Engineering Research
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• v.19 no.1
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• pp.19-24
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• 1998

The main goal of this paper is to propose and to test a radio protocol based CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) for the purpose of enhancing the existing medical information system. The feature of the new medical information system, Medical Application Radio System(MARS), which operating in real time is the transmission of medical information in bi-direction between the hospital control office and patients mobile stations. MARS monitors patients linked to the network by radio and provides quick alarm, flexible documentation capabilities, asnd fast treatment for the analysis of collected medical data. The existing medical information system, radio telemetry system which transfers the message of patients to the CAP(Central Access Point) unit in one way at the speed of 9.6Kbps and operates a channel frequency bandwidth. To verify the Performance of the proposed system, we have performed the numerical analysis and have implemented a test system which consists of the 2.4Ghz radio transceiver and personal computer.

• Proceedings of the Safety Management and Science Conference
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• 2011.11a
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• pp.23-34
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• 2011

Recently, carelessness on safety management in construction sites has caused a sharper upward trend in accidents and disasters, compared to the past. Therefore, this study analyzes the causes of accidents that occurred on construction sites in the year of 2010, and proposes preventive measures. The construction industry had a heavy death rate with 279 out of 418 deaths from falls in all industrial sites, accounting for 66.7%. And the causation analysis found a particularly high incidence of temporary structure-related accidents, with falling off scaffolding as the most common cause of accidents. According to the causation analysis of fall-down accident cases, accidents induced by protrusion on construction sites are a big contributor resulting in the deaths of 312, accounting for 74.8%, which is deemed to be due to site disorderliness. And to remove floor protrusions and to secure workers' traffic line and safety, neat and thorough site arrangement is necessary. Against collision, efforts must be made to prevent equipment-pedestrian crashes on site, which necessarily requires emergency lamps, alarm bells, and safety poles and blocks to be installed, lighting systems to be improved, obstacles to be removed, site supervisors to be assigned to construction equipment works, and workers to be more intensely trained and supervised.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.7-13
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• 2012

Recently, carelessness on safety management in construction sites has caused a sharper upward trend in accidents and disasters, compared to the past. Therefore, this study analyzes the causes of accidents that occurred on construction sites in the year of 2007, and proposes preventive measures. The construction industry had a heavy death rate with 279 out of 418 deaths from falls in all industrial sites, accounting for 66.7%. And the causation analysis found a particularly high incidence of temporary structure-related accidents, with falling off scaffolding as the most common cause of accidents. According to the causation analysis of fall-down accident cases, accidents induced by protrusion on construction sites are a big contributor resulting in the deaths of 312, accounting for 74.8%, which is deemed to be due to site disorderliness. And to remove floor protrusions and to secure workers' traffic line and safety, neat and thorough site arrangement is necessary. Against collision, efforts must be made to prevent equipment-pedestrian crashes on site, which necessarily requires emergency lamps, alarm bells, and safety poles and blocks to be installed, lighting systems to be improved, obstacles to be removed, site supervisors to be assigned to construction equipment works, and workers to be more intensely trained and supervised.

• Journal of English Language & Literature
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• v.59 no.4
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• pp.569-592
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• 2013

In Reservation Blues, Sherman Alexie examines how Indians can survive successfully in contemporary America, overcoming the tragic history of colonialists' violence and the resultant traumata. For Alexie, both reassembling the parts of the colonialist history through remembrance and testifying its unjustness play important roles not only in the decolonization process which probes the remnants and the negative effects of the colonialism deeply rooted in the lives of Indians but in the procedure of healing the political, cultural, and religious traumata. However, it should be noted that the ultimate aim of Alexie's decolonization does not lie in erasing every trace of the colonialism but in transforming its legacy into a story of survivance. The recovery of the tribal voices and the preservation of Indian traditions, blood, and cultures are essential in the survivance of Indians. Yet, Alexie's tribalism should not be viewed as an exclusive one. He knows well that it is neither possible nor desirable to maintain an exclusive tribalism based on blind adherence to a mythic or "pure" past. Exclusive tribalism is a cause for alarm in the contemporary world, a dynamic place where diverse cultures consistently change through collision, exchange, and negotiation. In Reservation Blues, Alexie stresses a spiritual and cultural flexibility that makes the cultural interpenetration possible as a key element of the meaningful survivance of contemporary American Indians.

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.229-237
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• 2004

In this paper, the design method and algorithms of the signal processor for a multipurpose radar system are analyzed. The signal processor, operating at the two modes-collision avoidance mode and weather mode, has 4 steps of ADC, NCI, STC, CFAR. Several algorithms of NCI and CFAR are analyzed and the optimal design is proposed to the system. CVI and CMLD algorithm have good performance in decreasing the false alarm rate and increasing detection probability, Regarding processor computational capacity, K=12 for CVI, M=16~20, Ko=M-4 for CMLD is suggested. CVI processing needs much time, two or more processors need to be allocated to CVI. So, for the system with four processors, two processors should be allocated to VID of NCI with ADC input and CFAR with STC, and two processors are should be allocated to CVI.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.2
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• pp.692-712
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• 2022

Buoys used for Aid to Navigation systems are widely used to guide the sea paths and are powered by batteries, requiring continuous battery replacement. However, since human labor is required to replace the batteries, humans can be exposed to dangerous situation, including even collision with shipping vessels. In addition, Maritime sensors are installed on the route signs, so that these are often damaged by collisions with small and medium-sized ships, resulting in significant financial loss. In order to prevent these accidents, maritime object detection technology is essential to alert ships approaching buoys. Existing studies apply a number of filters to eliminate noise and to detect objects within the sea image. For this process, most studies directly access the pixels and process the images. However, this approach typically takes a long time to process because of its complexity and the requirements of significant amounts of computational power. In an emergent situation, it is important to alarm the vessel's rapid approach to buoys in real time to avoid collisions between vessels and route signs, therefore minimizing computation and speeding up processes are critical operations. Therefore, we propose Fast Connected Component Labeling (FCCL) which can reduce computation to minimize the processing time of filter applications, while maintaining the detection performance of existing methods. The results show that the detection performance of the FCCL is close to 30 FPS - approximately 2-5 times faster, when compared to the existing methods - while the average throughput is the same as existing methods.