• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.259-261
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• 2017

SRK-BB(Skill-, Rule-, Knowledge-Based Behavior)는 주어진 사건을 처리할 때 인간이 행하는 행동을 체계적으로 식별하기 위한 하나의 이론이다. 이러한 SRK-BB에 대한 결과는 주어진 임무에 대한 '성공'과 '실패'로 나타낼 수 있다. 만약, 어느 사건에 대한 SRK-BB를 식별할 수 있고, 이에 대한 '성공/실패'의 결과를 알 수 있다면, SRK-BB를 이용하여 이들 사이에 연계된 확률적인 관계를 정립할 수 있다. 한편, 해양사고의 결과를 분석한 해양안전심판원의 재결서 또는 재결요약서에는 다양한 사고(즉, 실패한 사건)에 대해서 해기사가 어떠한 행동을 취했는지 상세하게 기록되어 있다. 이러한 해양안전심판원의 자료를 분석하면 실패한 해양사고에 대한 방대한 해기사의 SRK 분포를 확보할 수 있다. 본 연구의 목적은 다양한 해양사고에 나타난 해기사들의 행동을 SRK-BB로 식별한 후 해기사들이 추후 야기할 수 있는 인적오류를 예측하기 위한 모델 구축에 있다. 인적오류 모델을 구축하기 위해서는 우선 해양사고에 포함된 SRK 분포 분석이 필요하고, 시스템적인 입출력 관계를 통해서 SRK에 의한 인적오류의 결과를 예측하기 위한 예측 모델이 필요하다. 본 연구에서는 해기사의 인적오류에 의한 사고를 어떻게 SRK 분포를 이용하여 예측할 수 있는지에 대한 개념을 설명하고, 해양사고 데이터에서 획득한 SRK 분포의 의미와, SRK 분포를 이용하여 어떻게 해기사가 야기할 사고를 예측할 수 있는지에 대한 연구접근 방법을 소개하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2017.11a
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• pp.266-268
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• 2017

인적오류에 인한 사고는 매년 발생 중이고, 인적오류에 의한 해양사고는 과학적인 인적오류모델을 통해서 해결방안을 모색할 수 있다. 본 연구의 목적은 선박조종시뮬레이터를 이용하여 해기사의 SRK(Skill, Rule, Knowledge) 행동을 식별하기 위한 것이다. SRK 행동은 라스무센이 제안한 행동 이론으로, 본 연구에서는 주어진 상황에 대해서 해기사들이 나타내는 성공 또는 실패 행동을 식별하는데 적용하였다. 식별한 해기사들의 SRK 행동은 인적오류모델의 변수로 적용할 예정이다. 이에, 본 논문에서는 하나의 선행 연구로서 해기사들의 SRK 행동을 선박조종시뮬레이터를 이용하여 측정하는 방법과 측정에 필요한 도구 및 지금까지의 연구결과를 고찰하였다.

• Journal of Navigation and Port Research
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• v.40 no.1
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• pp.27-34
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• 2016

For the prevention of marine casualties, international bodies have mainly focused on strengthening ship's stability and design, maritime education and training, and improving maritime traffic environment. Statistics analysis on marine casualties showed that most of casualties occurred in coastal waters, especially by human elements. In order to review the conformity of existing prevention measures with the result of the statistics analysis, the IMO's SHELL model was applied to the established measures. As a result, ergonomic approaches were needed for the prevention of human errors in coastal waters, so that the priority should be given to the interface between ship's operator and navigational environment. For this study, Rasmussen's SRK pyramid, which showed decision making mechanism of human, and the US Coast Guard's investigation manual on marine casualties concerning the collapse of safe maritime transportation system were reviewed, and the merits and demerits within the risk assessment tools such as IWRAP, PAWSA, ES model, PARK model, and NURI model were also studied. Although the effectiveness of the existing risk assessment models was proved in ports and approaching channels, it is concluded that the need of new models for converting Korean seafarers' qualitative risk to quantitative risk was proposed so as to print hazard maps which make seafarers instinctively recognize comparative hazard levels of coastal waters.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.3
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• pp.21-29
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• 2013

Turbulent flow and thermal fields of gaseous hydrogen/liquid oxygen flames at supercritical pressure are investigated by turbulence models. The modified Soave-Redlich-Kwong (SRK) EOS is implemented into the flamelet model to realize real-fluid combustions. For supercritical fluid flows, the modified pressure-velocity-density coupling are introduced. Based on the algorithm, the relative performance of six convection schemes and the predictions of four turbulence models are compared. The selected turbulence models are needed to be modified to consider various characteristics of real-fluid combustions.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.550-554
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• 2023

Fossil energy sources are limited in their sustainable use and expansion due to global warming caused by carbon dioxide emissions. Hydrogen is considered as a promising alternative to traditional fossil fuels. To ensure the stable long-term storage, it is necessary to accurately predict its thermodynamic properties at cryogenic temperatures. Therefore, this study aimed to investigate thermodynamic properties, such as saturated vapor pressure and density, enthalpy, and entropy of liquid and gas, using cubic equations of state that demonstrate relatively simple relationships. Among the three types of equations of state (Redlich-Kwong (RK), Soave-Redlich-Kwong (SRK), and Peng-Robinson (PR)), the SRK model exhibited relatively accurate prediction results for various physical properties.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.85-88
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• 2010

This study has been mainly motivated to numerically model the supercritical mixing and combustion processes encountered in the liquid propellant rocket engines. In the present approach, turbulence is represented by the extended $k-{\varepsilon}$ turbulence model. To account for the real fluid effects, the propellant mixture properties are calculated by using SRK (Souve-Redlich-Kwong) equation of state. In order to realistically represent the turbulence-chemistry interaction in the turbulent nonpremixed flames, the flamelet approach based on the real fluid flamelet library has been adopted. Based on numerical results, the detailed discussions are made for the real fluid effects and the precise structure of gaseous methane/liquid oxygen coaxial jet flame.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.31-34
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• 2012

Numerical simulations of the steady and unsteady state were conducted for a coaxial swirl injector with Kerosene fuel. Non-premixed equilibrium model based on chemical equilibrium assumption was used as turbulence-chemistry interaction model. As an equations of state, SRK(Soave-Redlich-Kwong) EOS was applied to deal with the behavior of real fluid in a high pressure condition. Through the steady and unsteady computations, mean values of steady and time-averaged unsteady state were compared on the temperature and OH mass fraction and it was shown that the flame structure of steady state was different to that of time-averaged unsteady state.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• v.y2005m4
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• pp.183-188
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• 2005

This study targets to investigate thermal wave transfer in a droplet strongly coupled with acoustic pressure and its effects on combustion response. The one-dimensional vaporization model uses SRK equation of state and flash calculation method to obtain more accurate thermophysical properties and compute vapor-liquid equilibrium. Calculations of an n-pentane droplet exposed into a perturbing nitrogen gas is carried out in terms of different ambient gas pressures and wave frequencies. The thermal wave is transferred more effectively at lower frequencies, which results in the decrease in the amplitude of the response.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.19-23
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• 2010

Injection characteristics of a kerosene swirl injector of liquid rocket engine operating at supercritical environment have been investigated. Kerosene surrogate models are proposed to model the kerosene properties. Turbulent numerical model is based on large eddy simulation and contains Soave modification of Redlich-Kwong equation of state and Chung's model. Numerical analysis results at supercritical environment are compared with the one at transcritical condition. Differences of density and viscosity are analyzed at both liquid film and core gas in the swirl injector.

• Journal of the Korean Institute of Gas
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• v.10 no.2 s.31
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• pp.22-26
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• 2006

In this study, modeling and simulation works using Aspen Plus were carried out for DME separation and purification process of pilot plant for the daily production of 50 kg of DME. For modeling of the entire DME separation unit, NRTL liquid activity coefficient model was used for the prediction of liquid phase non-idealities, Henry's law option was also used for the estimation of solubilities of light gases in solvents and SRK equation of state model was utilized for the description of vapor phase non-idealities. DME having over 98 wt% purity was obtained as a side distillate product in a DME purification column.