• Journal of the Korean Institute of Gas
• /
• v.10 no.1 s.30
• /
• pp.32-37
• /
• 2006

Major components of refinery plants are exposed to various damage mechanisms depending on the operation condition, material selection and kinds of internal fluid. Inspection techniques and damage monitoring methods should be selected considering the damage mechanisms of the components. Hence, it is quite necessary to have an information system with a standardized database on the various damage mechanisms. In this study a damage information system with contents on the damage mechanisms included in API 571 code was developed. Concept of the screening table employed in USA and Japan was also adopted to identify the probable damage mechanisms from the information on operating temperature, internal fluid, metal used for the component and stress condition. This system can be used before the risk based inspection planning to identify key damage mechanisms involved.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.41 no.9
• /
• pp.571-577
• /
• 2017

In this numerical study, the separation efficiency of three-phase separator in an oil-sand plant was studied with various inlet head configurations. The free water knockout (FWKO) vessel was designed with a flow rate of $15.89m^3/day$ (100 bbl/day) and the SOR(stream-to-oil ratio)=3.5 was derived using Stokes' law. For modularization, optimization of the design of the inlet head configuration was performed with parallel-connected dual FWKO vessels. The feed condition of bitumen emulsion was API=17, $T_{in}=150^{\circ}C$ and $P_{in}=50bar$. A mean residence time was determined the time when 95% of the oil and water in FWKO vessel was separated. The combination between the volume of fluid (VOF) and the discrete phase model (DPM) was used to simulate the phase separation phenomenon in a multi-phase separator. Furthermore, in order to calculate multi-phase flow the pseudo-transient method was adopted.

• Journal of the Korean Society of Safety
• /
• v.24 no.1
• /
• pp.31-36
• /
• 2009

This paper focuses on techniques of improving refinery reliability, availability, and profitability. Our team developed a corrosion control document(CCD) for processing of the crude distillation unit(CDU). Recent study shows the loss due to corrosion in US is around $276 billion. It's a big concern for both managers and engineers of refinery industry. The CCD consists of numerous parts namely damage mechanism(DM), design data, critical reliability variable(CRV), guidelines, etc. The first step in the development of CCD is to build material selection diagram(MSD). Damage mechanisms affecting equipments and process need to be chosen carefully based on API 571. The selected nine DM from API 571 are (1) creep/stress rupture, (2) fuel ash corrosion, (3) oxidation, (4) high temperature sulfidation, (5) naphthenic acid corrosion, (6) hydrochloric acid(HCL) corrosion, (7) ammonium chloride(salt) corrosion, (8) wet $H_2S$ corrosion, and (9) ammonia stress corrosion cracking. Each DM related to corrosion of CDU process was selected by design data, P&ID, PFD, corrosion loop, flow of process, equipment's history, and experience. Operating variables affecting severity of DM are selected in initial stage of CRV. We propose the guidelines for reliability of equipments based on CRV. The CCD has been developed on the basis of the corrosion control in refinery industry. It also improves the safety of refinery process and reduces the cost of corrosion greatly.

• Corrosion Science and Technology
• /
• v.7 no.6
• /
• pp.350-361
• /
• 2008

Canada's oil sands contain one of the largest reserves of oil in the world. According to recent estimates, there are nearly 180 billion barrels of oil in the Canadian oil sands trapped in a complex mixture of sand, water and clay. More than 40 companies have been currently operating or developing oil sands facilities since the first production in 1967. The process of oil sands upgrading is similar with down stream refinery, but the corrosion environment in upgrading refinery is often more severe than in the refinery because of high chlorides, mineral contents, carbonic acid, heavy viscosity and fouling, higher naphthenic acid [$NA-R(CH_{2})nCOOH$], and greater sulfur contents. Naphthenic acid corrosion (NAC) which is one of the most critical corrosion issues in up & downstream refinery plants was observed for the first time in 1920's in refinery distillation processes of Rumania, Azerbaizan (Baku), Venezuela, and California. As a first API report, the 11th annual meeting stated sources and mechanism of NAC in early 1930's. API has been developing the risk base standards, such as API RP580, 571, and Publication 581 which are based on the worst NAC damage in the world since 2000. Nevertheless not only the NAC phenomena and control in Canadian sands oil process are not much widely known but also there are still no engineering guidances for the Canadian sands oil in API standards. This paper will give NAC phenomina and materials selection guidance against NA environment in Canadian oil sands upgrading processes.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.31 no.4
• /
• pp.559-571
• /
• 2021

Along with the increase prevalence of computers, the number of malware distributions by attackers to ordinary users has also increased. Research to detect malware continues to this day, and in recent years, research on malware detection and analysis using AI is focused. However, the AI algorithm has a disadvantage that it cannot explain why it detects and classifies malware. XAI techniques have emerged to overcome these limitations of AI and make it practical. With XAI, it is possible to provide a basis for judgment on the final outcome of the AI. In this paper, we conducted malware group classification using XGBoost and Random Forest, and interpreted the results through SHAP. Both classification models showed a high classification accuracy of about 99%, and when comparing the top 20 API features derived through XAI with the main APIs of malware, it was possible to interpret and understand more than a certain level. In the future, based on this, a direct AI reliability improvement study will be conducted.

• The Journal of the Korea Contents Association
• /
• v.15 no.11
• /
• pp.571-581
• /
• 2015

In the field of Korean medicine (KM), KM terms has been mixed used for a long period. After the Society of KM had systematically organized the KM terms used in our country, the book for the Korean medical standard terminologies was published. In this study, we developed an online service based on the book. The online service provides various useful functions for searching the terms and their commentary and collecting users' opinions. Users can also compare the standard terms with their semantic search results and naver's knowledge search results within our system. By analyzing logs of our system, we suggested several directions for future development, including the improvement of search functions, advertisements, and the provision of open APIs. In the future, our online service might provide the important information on clinics, academic researches, and international standards.

• The Journal of the Korea Contents Association
• /
• v.20 no.2
• /
• pp.561-571
• /
• 2020

Location information service using big data is continuously developing. In terms of navigation, the range of services from map API service to ship navigation information has been expanded, and system application information has been extended to SNS and blog search records for each location. Recently, it is being used as a new industry such as location-based search and advertisement, driverless cars, Internet of Things (IoT) and online to offline (O2O) services. In this study, we propose an information system that enables users to receive information about nearby stores more effectively by using big data when a user moves a specific route. In addition, we have designed this system so that local stores can use this system to effectively promote it at low cost. In particular, we analyzed web-based information in real time to improve the accuracy of information provided to users by complementing the data. Through this system, system users will be able to utilize the information more effectively. Also, from a system perspective, it can be used to create new services by integrating with various web services.

• Journal of the Korean Society of Safety
• /
• v.35 no.6
• /
• pp.78-84
• /
• 2020

The F&EI technique is one of the risk assessments with many advantages. It can save time and effort compared to quantitative risk assessment (QRA). By using the evaluation result of this technique, it is possible to check the effectiveness of the investment cost. In addition, a relative risk ranking can be created and used to establish the facility management cycle and to prioritize investment. However, evaluating the target process can be evaluated more than the actual risk since the LCCF, a loss prevention measure, is too limited. In addition, calculating premiums via this method can result in excessive premiums, making it difficult to evaluate the risk precisely. Therefore, new safety guard was added to the LCCF of the F&EI risk assessment with reference to HAZOP and LOPA techniques. Newly added LCCFs are Deflagration arrester, Check valve, SIS, and Vacuum beaker, etc. As a case study, F&EI risk assessment was performed on Acetone storage tank of a API (Active pharmaceutical ingredient) plant to compare actual MPPD. The estimated loss amount was 592,558$ for the existing technique and 563,571$ for the improved technique, which was reduced by about 5% compared to the previous one.This proved that a more precise evaluation is possible and that the efforts for safety at the workplace are reflected in the evaluation results.