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Legislation on Aid in Dying in France (조력사망에 관한 프랑스의 입법 동향)

  • Jieun Lee
    • The Korean Society of Law and Medicine
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    • v.25 no.1
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    • pp.193-222
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    • 2024
  • From a global trend, discussions on the patient's death with dignity are gradually progressing from the issue of withdrawal of life-sustaining treatment to the issue of whether to allow assisted death and its requirements. Several states in the United States and Western European countries such as Canada, Belgium, and the Netherlands have institutionalized treatment to accelerate the time of death through the assistance of doctors. In France, after a long period of raising and reviewing issues, discussions on related legislation are taking place at a slower pace than in other European countries. In France, social discussions and legislative attempts on death with dignity have been actively conducted since the late 20th century. The Leonetti Act of 2005 prohibited the continuation of meaningless treatment against the will of patients, and after the Clay-Leonetti Act of 2016, it was legalized to administer intensive and continuous sedatives to patients until death. However, unlike many neighboring European countries, treatment that speeds up the time of death itself is still prohibited in France, even if the patient wants. As the existential and universal question of whether to allow dying patients to die painlessly with the help of a doctor has recently emerged as an important issue, a number of lawmakers have submitted legislation to legalize assisted death. This paper examines the legislative process developed in relation to patients' rights to dignified death in France, and compares and reviews French legislation that attempts to legalize assisted death with the amendment to the Korean Life-Sustaining Treatment Act.

Estimation of a 9.77 G/T Small Fishing Vessel's Operating Performance Depending on Forward Speed Based on 3-DoF Captive Model Tests (9.77톤급 소형어선의 3자유도 구속모형시험을 통한 선속 별 운항성능 추정)

  • Dong-Jin Kim;Haeseong Ahn;Kyunghee Cho;Dong Jin Yeo
    • Journal of Navigation and Port Research
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    • v.47 no.6
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    • pp.305-314
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    • 2023
  • In this study, a mathematical model of a 9.77 G/T small fishing vessel was established based on captive model tests. The powering and manoeuvring performances of the vessel in the harbor and coastal sea were focused on, so captive model tests were conducted up to the full-scale speed of 8 knots. Propeller open water, resistance, and self-propulsion tests of a 1/3.5-scaled model ship were performed in a towing tank, and the full-scale powering performance was predicted. Hydrodynamic coefficients in the mathematical model were obtained by rudder open water, horizontal planar motion mechanism tests of the same model ship. In particular, in static drift and pure yaw tests which were conducted at a speed of 2 to 8 knots, the linear hydrodynamic coefficients varied with the ship speed. The effect of the ship speed on the linear coefficients was considered in the mathematical model, and manoeuvring motions, such as turning circles and zig-zags, were simulated with various approach speeds and analyzed.

Numerical and experimental analysis of aerodynamics and aeroacoustics of high-speed train using compressible Large Eddy Simulation (압축성 대와류모사를 이용한 고속열차의 공력 및 공력소음의 수치적/실험적 분석)

  • Kwongi Lee;Cheolung Cheong;Jaehwan Kim;Minseung Jung
    • The Journal of the Acoustical Society of Korea
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    • v.43 no.1
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    • pp.95-102
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    • 2024
  • Due to technological advances, the cruising speed of high-speed trains is increasing, and aerodynamic noise generated from the flow outside the train has been an important consideration in the design stage. To accurately predict the flow-induced noise, high-resolution generation of sound sources in the near field and low-dissipation of sound propagation in the far field are required. This should be accompanied by a numerical grid and time resolution that can properly consider both temporal and spatial scales for each component of the real high-speed train. To overcome these challenges, this research simultaneously calculates the external flow and acoustic fields of five high-speed train cars of real-scale and at operational running speeds using a threedimensional unsteady Large Eddy Simulation technique. To verify the numerical analysis, the measurements of the wall pressure fluctuation and numerical results are compared. The Ffowcs Williams and Hawking equation is used to predict the acoustic power radiated from the high-speed train. This research is expected to contribute to noise reduction based on the analysis of the aerodynamic noise generation mechanism of high-speed trains.

Overview of the Korean Marine Industry and VPP Analysis of a 28ft Sailing Yacht (대한민국의 해양 레저 시장 및 28ft급 세일요트의 VPP 성능해석 연구)

  • Yeongmin Park;Hoyun Jang;Minsu Kang
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.30 no.4
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    • pp.365-372
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    • 2024
  • The South Korean marine industry is emerging as a significant market, driven by the growing popularity of various water leisure activities, including sailing. This trend suggests a rising demand for sailing yachts. Consequently, since 2022, the design and development of a 28ft sailing yacht have been ongoing, supported by the government and the Ministry of Oceans and Fisheries, to promote yachting culture in South Korea. The Velocity Prediction Program (VPP) analysis was conducted using WinDesign during the preliminary design stage to evaluate performance and determine design parameters. The hydrodynamic model used for this vessel is based on regression methods developed from years of experience in naval architecture and yacht research at the Wolfson Unit, providing reliable estimates for most modern yachts. However, owing to the lack of specific hydrodynamic data from towing tank tests or CFD numerical analysis, verification of the hydrodynamic model has faced some challenges. Additionally, an incomplete weight estimate resulted in variable VCG values, potentially affecting stability and overall performance. The optimal boat speed for this vessel was determined at true wind speeds (TWS) of 4, 8, 12, 16, and 20 knots, using both the jib (up to 120° TWA) and the spinnaker (from 80° TWA). The optimized speed of the yacht was found to be comparable to that of international similar-class yachts.

A Study of Wind Characteristics around Nuclear Power Plants Based on the Joint Distribution of the Wind Direction and Wind Speed

  • Yunjong Lee
    • Journal of Radiation Industry
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    • v.17 no.3
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    • pp.299-307
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    • 2023
  • Given that toxic substances are diffused by the various movements of the atmosphere, it is very important to evaluate the risks associated with this phenomenon. When analyzing the behavioral characteristics of these atmospheric diffusion models, the main input data are the wind speed and wind direction among the meteorological data. In particular, it is known that a certain wind direction occurs in summer and winter in Korea under the influence of westerlies and monsoons. In this study, synoptic meteorological observation data provided by the Korea Meteorological Administration were analyzed from January 1, 2012 to the end of August of 2022 to understand the regional wind characteristics of nuclear power plants and surrounding areas. The selected target areas consisted of 16 weather stations around the Hanbit, Kori, Wolsong, Hanul, and Saeul nuclear power plants that are currently in operation. The analysis was based on the temperature, wind direction, and wind speed data at those locations. Average, maximum, minimum, median, and mode values were analyzed using long-term annual temperature, wind speed, and wind direction data. Correlation coefficient values were also analyzed to determine the linear relationships among the temperature, wind direction, and wind speed. Among the 16 districts, Uljin had the highest wind speed. The median wind speed values for each region were lower than the average wind speed values. For regions where the average wind speed exceeds the median wind speed, Yeongju, Gochang, Gyeongju, Yeonggwang, and Gimhae were calculated as 0.69 m s-1, 0.54m s-1, 0.45m s-1, 0.4m s-1, and 0.36m s-1, respectively. The average temperature in the 16 regions was 13.52 degrees Celsius; the median temperature was 14.31 degrees and the mode temperature was 20.69 degrees. The average regional temperature standard deviation was calculated and found to be 9.83 degrees. The maximum summer temperatures were 39.7, 39.5, and 39.3 in Yeongdeok, Pohang, and Yeongcheon, respectively. The wind directions and speeds in the 16 regions were plotted as a wind rose graph, and the characteristics of the wind direction and speed of each region were investigated. It was found that there is a dominant wind direction correlated with the topographical characteristics in each region. However, the linear relationship between the wind speed and direction by region varied from 0.53 to 0.07. Through this study, by evaluating meteorological observation data on a long-term synoptic scale of ten years, regional characteristics were found.

Research on Optimized Operating Systems for Implementing High-Efficiency Small Wind Power Plants (고효율 소형 풍력 발전소 구현을 위한 최적화 운영 체계 연구)

  • Young-Bu Kim;Jun-Mo Park
    • Journal of the Institute of Convergence Signal Processing
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    • v.25 no.2
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    • pp.94-99
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    • 2024
  • Recently, wind power has been gaining attention as a highly efficient renewable energy source, leading to various technological developments worldwide. Typically, wind power is operated in the form of large wind farms with many wind turbines installed in areas rich in wind resources. However, in developing countries or regions isolated from the power grid, off-grid small wind power systems are emerging as an efficient solution. To efficiently operate and expand off-grid small-scale power systems, the development of real-time monitoring systems is required. For the efficient operation of small wind power systems, it is essential to develop real-time monitoring systems that can actively respond to excessive wind speeds and various environmental factors, as well as ensure the stable supply of produced power to small areas or facilities through an Energy Storage System (ESS). The implemented system monitors turbine RPM, power generation, brake operation, and more to create an optimal operating environment. The developed small wind power system can be utilized in remote road lighting, marine leisure facilities, mobile communication base stations, and other applications, contributing to the development of the RE100 industry ecosystem.

Standards for Use of Tugboats to Accommodate Increase in Ship Size - Case for Mokpo New Port Automobile Terminal - (선박 대형화에 따른 예선 사용 기준에 관한 연구 - 목포신항 자동차부두를 중심으로 -)

  • Chang-Hyun Jung;Deug-Bong Kim;Jae-Yong Jeong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.30 no.5
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    • pp.442-449
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    • 2024
  • The pilotage rate of car carriers at Mokpo New Port is increasing and ships are becoming larger. In this study, wind pressure and hydraulic force are calculated to determine the horsepower required of a tugboat to safely operate a 7,500 unit car carrier entering Mokpo New Port. At the Mokpo New Port automobile pier, the maximum flood and ebb currents are 1.6 and 0.7 kts, respectively, at a point 1.0 km away from the pier. In such conditions, the required tugboat standards are satisfied only in the case of "ebb current and westerly wind" under certain situations. Under a current of 0.5 kts, for the case of "ebb current and easterly wind," the required tugboat standards are satisfied only in certain situations, whereas for the case of " flood current and westerly wind," berthing or unberthing is impossible at wind speeds of 18 kts or higher. Additionally, in cases without any current, if the wind speed exceeds 21 kts, then the current standards for the required tugboat are not satisfied. Therefore, for large car carriers of approximately 70,000 G/T entering Mokpo New Port, they are planed to the vessel's docking point when the current speed is less than 0.5 kts. However, when the current and wind speed exceed 0.5 and 20 kts, respectively, the horsepower of the tugboat must be increased accordingly.

Development of Database-Based Pedestrian Accident Scenarios and Analysis of Accident Prevention Effects from V2X Application (데이터베이스 기반의 보행자 사고 시나리오 개발 및 V2X 적용에 따른 사고예방 효과 분석)

  • Seryong Baek;Yoowon Kim;Taehyun Yoo;Cheonho Kim
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.23 no.5
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    • pp.274-292
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    • 2024
  • The purpose of this study is to develop test scenarios utilizing V2X (Vehicle-to-Everything) communication technology for the prevention of pedestrian accidents and to validate these scenarios through simulation. To this end, this researcher used existing traffic accident databases to categorize vehicle-to-pedestrian accident data, and drew key accident patterns through the analysis of accident types and the speeds of pedestrians and vehicles. Based on the analyzed data, scenarios were established where V2X technology can be applied under various conditions of pedestrians and vehicles. These scenarios were specifically classified into conditions where physical avoidance of an accident is impossible and conditions where accident avoidance is possible through V2X technology. In the developed test matrix, simulations were conducted in diverse scenarios to evaluate the performance of the V2X-based accident prevention system. The research results confirmed that the application of V2X technology is effective for preventing pedestrian accidents. It is expected that these scenarios can serve as standardized guidelines for future traffic safety improvements. This study provides useful data for policymakers for traffic safety, vehicle manufacturers, and technology developers, and proposes a new approach to enhance pedestrian safety.

Evaluation of Maintenance Quantity and Life Cycle Costs of Railway Track Considering Evolution of Rail Fatigue Damage and Ballast Settlement According to Track Quality Level (궤도 품질수준에 따른 레일 피로 손상과 자갈 침하 진전을 고려한 철도 궤도 보수량 및 수명주기비용 평가)

  • Jun-Hyuck Choi;Seung-Yup Jang;Seung-Won You;Do-Yeop Kim;Hyung-Jo Kim
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.28 no.4
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    • pp.37-47
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    • 2024
  • This study proposes a track maintenance quantity estimation model that considers evolution of rail fatigue damage and ballast settlement based on actual maintenance data from the Gyeongbu high-speed railway, and revises the existing life cycle cost (LCC) model for railway track. Using this model, maintenance quantities and life cycle costs based on different track quality levels are evaluated and discussed. According to the results, it is confirmed that applying the track maintenance quantity estimation model that accounts for rail fatigue damage and ballast settlement allows us to reasonably estimate maintenance costs close to the actual data. The track quality coefficient significantly influences both rail and ballast maintenance quantities, with ballast maintenance having a greater impact than rail maintenance. Additionally, as train speed increases, both rail and ballast maintenance quantities rise. Moreover, a higher track quality coefficient leads to a steeper increase in maintenance quantities with increasing train speed. Consequently, LCC also exhibits a faster growth rate over time with higher track quality coefficients and faster train speeds, resulting from an increased proportion of maintenance costs.

Effects of Environmental Conditions on Vegetation Indices from Multispectral Images: A Review

  • Md Asrakul Haque;Md Nasim Reza;Mohammod Ali;Md Rejaul Karim;Shahriar Ahmed;Kyung-Do Lee;Young Ho Khang;Sun-Ok Chung
    • Korean Journal of Remote Sensing
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    • v.40 no.4
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    • pp.319-341
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    • 2024
  • The utilization of multispectral imaging systems (MIS) in remote sensing has become crucial for large-scale agricultural operations, particularly for diagnosing plant health, monitoring crop growth, and estimating plant phenotypic traits through vegetation indices (VIs). However, environmental factors can significantly affect the accuracy of multispectral reflectance data, leading to potential errors in VIs and crop status assessments. This paper reviewed the complex interactions between environmental conditions and multispectral sensors emphasizing the importance of accounting for these factors to enhance the reliability of reflectance data in agricultural applications.An overview of the fundamentals of multispectral sensors and the operational principles behind vegetation index (VI) computation was reviewed. The review highlights the impact of environmental conditions, particularly solar zenith angle (SZA), on reflectance data quality. Higher SZA values increase cloud optical thickness and droplet concentration by 40-70%, affecting reflectance in the red (-0.01 to 0.02) and near-infrared (NIR) bands (-0.03 to 0.06), crucial for VI accuracy. An SZA of 45° is optimal for data collection, while atmospheric conditions, such as water vapor and aerosols, greatly influence reflectance data, affecting forest biomass estimates and agricultural assessments. During the COVID-19 lockdown,reduced atmospheric interference improved the accuracy of satellite image reflectance consistency. The NIR/Red edge ratio and water index emerged as the most stable indices, providing consistent measurements across different lighting conditions. Additionally, a simulated environment demonstrated that MIS surface reflectance can vary 10-20% with changes in aerosol optical thickness, 15-30% with water vapor levels, and up to 25% in NIR reflectance due to high wind speeds. Seasonal factors like temperature and humidity can cause up to a 15% change, highlighting the complexity of environmental impacts on remote sensing data. This review indicated the importance of precisely managing environmental factors to maintain the integrity of VIs calculations. Explaining the relationship between environmental variables and multispectral sensors offers valuable insights for optimizing the accuracy and reliability of remote sensing data in various agricultural applications.