• Title/Summary/Keyword: Storage Vessel

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A Study on Freezing Efficiency Improvement of Horizontal-Plate Freezer for Fishing Vessel (어선용 수평 냉각판 냉동장치의 냉동 효율 개선에 관한 연구)

  • Lee, Jae-Chul;Jeong, Ji-Ho;Kim, Byung-Mok;Shin, Sung-Chul;Kim, Soo-Young;Jeong, Bo-Yong
    • Journal of the Society of Naval Architects of Korea
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    • v.52 no.1
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    • pp.19-24
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    • 2015
  • The economic efficiency for fishery products can be related to their freshness and the quality. In order to freshly storage the product, freezing equipment system is necessary for fishing vessels. For this purpose, the horizontal plate freezer (HPF) is mostly used. In this research, our major objective is to improve the freezing performance of the HPF. Therefore, it is important to analyse the relationship between the shape of channels and the cooling temperature of the HPF. In order to save calculation time while checking the trend analysis between shape and performance, we used scaled models, and evaluate the cooling temperature of full scale model based on trend analysis results. The produced HPF in domestic was used, and the same operating conditions are considered. Based on this paper, the future research will be a comparison and verification through the experiments.

Motion and Sloshing Analysis for New Concept of Offshore Storage Unit

  • Ha, Mun-Keun;Kim, Mun-Sung;Paik, Bu-Keun;Park, Chung-Hum
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • v.5 no.1
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    • pp.22-28
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    • 2002
  • A New concept for the LNG-FPSO ship, with moonpool and bilge step in bottom, is proposed. This concept is investigated with regard to motion reduction and sloshing phenomena of the cargo and operation tanks. The principal dimensions of the ship are $L\timesb B\times D\times t(design)=270.0\times51.0\times32.32\times13.7(m)$, with a total cargo capacity of 161KT; a 98% loading condition is considered for this study. The moonpools and rectangular step at the bilge have been designed for the purpose of decreasing the motion within the tank. For the motion analysis, linearized three-dimensional diffraction theory, with the simplified boundary condition was used. The six-degree of freedom coupled motion responses were calculated for the LNG-FPSO ship. Viscous effects on the roll motion responses of a vessel were taken into account in this calculation program, using an empirical formula suggested by Himeno(1981). The case study for the moonpool size has been conducted using theoretical estimation and the experimental method. For the optimization of the moonpool size and effect of the bilge step, 9 cases of its size, both with and without bilge step, were involved in the study. no motion responses, especially roll motion, for the designed LNG-FPSO ships are much lower than those of other drill ships and shuttle tankers. The limit criterions are satisfied. To check the cargo tank and operation tank sizes, we performed a sloshing analysis in the irregular waves which focuses on the pressure distribution on the tank wall and the time history of pressure and free surface for No.2 and 5 tanks of LNG-FPSO with chamfers. Finally, optimum tank sire was estimated.

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Integrated Level 1-Level 2 decommissioning probabilistic risk assessment for boiling water reactors

  • Mercurio, Davide;Andersen, Vincent M.;Wagner, Kenneth C.
    • Nuclear Engineering and Technology
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    • v.50 no.5
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    • pp.627-638
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    • 2018
  • This article describes an integrated Level 1-Level 2 probabilistic risk assessment (PRA) methodology to evaluate the radiological risk during postulated accident scenarios initiated during the decommissioning phase of a typical Mark I containment boiling water reactor. The fuel damage scenarios include those initiated while the reactor is permanently shut down, defueled, and the spent fuel is located into the spent fuel storage pool. This article focuses on the integrated Level 1-Level 2 PRA aspects of the analysis, from the beginning of the accident to the radiological release into the environment. The integrated Level 1-Level 2 decommissioning PRA uses event trees and fault trees that assess the accident progression until and after fuel damage. Detailed deterministic severe accident analyses are performed to support the fault tree/event tree development and to provide source term information for the various pieces of the Level 1-Level 2 model. Source terms information is collected from accidents occurring in both the reactor pressure vessel and the spent fuel pool, including simultaneous accidents. The Level 1-Level 2 PRA model evaluates the temporal and physical changes in plant conditions including consideration of major uncertainties. The goal of this article is to provide a methodology framework to perform a decommissioning Probabilistic Risk Assessment (PRA), and an application to a real case study is provided to show the use of the methodology. Results will be derived from the integrated Level 1-Level 2 decommissioning PSA event tree in terms of fuel damage frequency, large release frequency, and large early release frequency, including uncertainties.

Damage Effects Modeling by Chlorine Leaks of Chemical Plants (화학공장의 염소 누출에 의한 피해 영향 모델링)

  • Jeong, Gyeong-Sam;Baik, Eun-Sun
    • Fire Science and Engineering
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    • v.32 no.3
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    • pp.76-87
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    • 2018
  • This study describes the damage effects modeling for a quantitative prediction about the hazardous distances from pressurized chlorine saturated liquid tank, which has two-phase leakage. The heavy gas, chlorine is an accidental substance that is used as a raw material and intermediate in chemical plants. Based on the evaluation method for damage prediction and accident effects assessment models, the operating conditions were set as the standard conditions to reveal the optimal variables on an accident due to the leakage of a liquid chlorine storage vessel. A model of the atmospheric diffusion model, ALOHA (V5.4.4) developed by USEPA and NOAA, which is used for a risk assessment of Off-site Risk Assessment (ORA), was used. The Yeosu National Industrial Complex is designated as a model site, which manufactures and handles large quantities of chemical substances. Weather-related variables and process variables for each scenario need to be modelled to derive the characteristics of leakage accidents. The estimated levels of concern (LOC) were calculated based on the Gaussian diffusion model. As a result of ALOHA modeling, the hazardous distance due to chlorine diffusion increased with increasing air temperature and the wind speed decreased and the atmospheric stability was stabilized.

Experimental Evaluation of Internal Blast Resistance of Prestressed Concrete Tubular Structure according to Explosive Charge Weight (프리스트레스트 콘크리트 관형 구조물의 폭발량에 따른 내부폭발저항성능에 관한 실험적 평가)

  • Choi, Ji Hun;Choi, Seung Jai;Yang, Dal Hun;Kim, Jang-Ho Jay
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.39 no.3
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    • pp.369-380
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    • 2019
  • When a extreme loading such as blast is applied to prestressed concrete (PSC) structures and infrastructures for an instantaneous time, serious property damages and human casualties occur. However, a existing design procedure for PSC structures such as prestressed containment vessel (PCCV) and gas storage tank do not consider a protective design for extreme internal blast scenario. Particularly, an internal blast is much more dangerous than that of external blast. Therefore, verification of the internal blast loading is required. In this paper, the internal blast resistance capacity of PSC member is evaluated by performing internal blast tests on RC and bi-directional PSC scaled down specimens. The applied internal blast loads were 22.68, 27.22, and 31.75 kg (50, 60, and 70 lbs) ANFO explosive charge at 1,000 mm standoff distance. The data acquisitions include blast pressure, deflection, strain, crack patterns, and prestressing force. The test results showed that it is possible to predict the damage area to the structure when internal blast loading occurs in PCCV structures.

Study about porous of Korean traditional pottery (한국전통옹기의 통기성에 관한연구)

  • Kim, Seok-Ho
    • Journal of Science of Art and Design
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    • v.9
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    • pp.5-24
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    • 2006
  • Human hunted and picked to survive and a vessel was made naturally to store something being hunted and picket, which was a great invention. In modern times, society changed and development of science gave us convenience in making a vessel and various kinds of store instruments which was made of pure natural material, of new stuff, such as plastic and iron. but human became to be inclined to regress into nature because of problems of environment. We can say that the representative trend is well-being, after all this is a symptom to return to life being persued by predecessors before the science civilization was developed. Ancestors have lived with nature, adapted themselves to it. For examples they have built the house which became to be a part of nature and just like it, and studied a method of storing food to eat for four seasons, then displayed a storagehouse and storage containers everywhere of the house. Now Korean has the custody of kimchi in refrigerator at every house, but our forefathers controled a timing to eat food with studying a method of storage to put to use nature. With hot wind of well-being, Korean food is becoming to be globalized, according to this, concern about the wisdom of progenitors is growing more and more. It's an example that the world shows concern seriously about the pottery, which have stored kimchi for a long time fleshly, in globalization of kimchi. This study have three purposes, the first. checking documents about the development history of pottery which is a kind of ceramic, and then the second, through an scientific experiment, with studying characteristic of pottery being built by the wisdom of ancestors, informing the merit of pottery and necessity to the world, and futhermore, the third, working up the development of close environmental vessels putting to use the characteristic of pottery.

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Effect of NaCl on the Stability of Oncolytic Vaccinia Virus (항암 백시니아 바이러스의 안전성에 대한 염화나트륨의 효과)

  • Kim, Seong-Geun;Ran, Gui Shao;Kwon, Hyuk-Chan;Hwang, Tae-Ho
    • Journal of Life Science
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    • v.26 no.1
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    • pp.23-33
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    • 2016
  • Pexa-Vec (JX-594) is a specific cancer-targeted oncolytic and immunotherapeutic vaccinia virus. The purpose of this study was to develop methods to maximize the stability of Pexa-Vec. In short-term instability testing, viral activity was rapidly decreased both at 4℃ and at room temperature (RT), but it was completely restored after sonication followed by vortex. Long-term stability testing of Pexa-Vec in the following liquid formulations was performed: (A) 30 mM Tris/pH 7.6, (B) 30 mM Tris/pH 8.6, (C) 30 mM Tris/pH 7.6, 150 mM NaCl, 15% sucrose, (D) 30 mM Tris/pH 7.6, 15% sucrose, and (E) 30 mM Tris/pH 8.6, 15% sucrose. Viral activity decreased less than 2 log10 at 4℃, and RT was observed in 3 days in B, while viral activity was not decreased even after 4–8 weeks at 4℃ and at 1 week in RT in A, suggesting that neutral pH may be essential to maintain virus stability. The addition of 15% sucrose into A (D) significantly increased viral stability at −20℃, 4℃, or RT, and it was also observed at pH 8.6 (E). The addition of 150 mM NaCl into D (C) significantly increased viral stability in addition to the sucrose effect at 4℃ or RT. Accordingly, the viral activity in formulation C was maintained for 1.5 years at 4℃, and for 1-2 weeks in RT. In conclusion, we propose that formulation C can provide the most adequate condition for the proper storage of vaccinia oncolytic virus.

Analysis of Citizen's Attitude to the Foodwaste (II) (음식쓰레기에 관한 실태조사(II))

  • Jang, Won;Kim, Mikyeong;Kang, Changmin;Park, Youngsuk
    • Journal of the Korea Organic Resources Recycling Association
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    • v.5 no.1
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    • pp.53-61
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    • 1997
  • This study was conducted to analysis citizen's attitude and style to the foodwaste from l0th Sept. to 30th Sept. in 1996. The research was used questionare method and analysis was used prequency analysis and cross table method by SPSS (scientific statistics). The foodwaste of householdwaste account for 24.8%, and the magnitude by the kinds of garbage were waste from pre-cocking stage, fruitshell, foodwaste remained after eating, septic foodwaste during storage. The more the housewives'age are young, foodwaste volumne were much. Most remained foodwaste after eating were soup and pot stew. The main cause of foodwaste production was overvolumne cooking. 88.8% of answers think that a menu can be useful to reduce foodwaste. The survey showed that 87.3% of answers put into the meter-rate bag after removed wetness of garbage. 84.1% of answers thought that the recycling of foodwaste needed, but the practical housewife was only 21%. For the suitable treatment of foodwaste, Survey showed that the consistent policy of goverment and continuous publicity was needed essentially, and that the public notice of TV or radio was effective. All of answers would like to participate in recycling of foodwastes whether public-posting or personal-posting. To set up vessel of posting at household, the proper purchase price and space of institution are needed, also the solution of sanitory & aesthetic problem and the collection of composting-product must be achieved smoothly.

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Damage Evaluation of Bi-directionally Prestressed Concrete Panels under Blast-fire Combined Loading (폭발 후 화재하중 시나리오에 따른 2방향 프리스트레스트 콘크리트 패널부재의 손상도 평가)

  • Choi, Ji-Hun;Choi, Seung-Jai;Kim, Tae-Kyun;Kim, Jang-Ho Jay
    • Journal of the Korea Concrete Institute
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    • v.29 no.3
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    • pp.237-248
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    • 2017
  • Frequent terror or military attack by explosion, impact, fire accidents have occurred recently. These attacks and incidents raised public concerns and anxiety of potential terrorist attacks on important infrastructures. However, structural behavioral researches on prestressed concrete (PSC) infrastructures such as Prestressed Concrete Containment Vessel (PCCV) and Liquefied Natural Gas (LNG) storage tanks under extreme loading are significantly lacking at this time. Also, researches on possible secondary fire scenarios after terror and bomb explosion has not been performed yet. Therefore, a study on PSC structural behavior from an blast-induced fire scenario was undertaken. To evaluate the blast-fire combined resistance capacity and its protective performance of bi-directional unbonded PSC member, blast-fire tests were carried out on $1,400mm{\times}1,000mm{\times}300mm$ PSC specimens. Blast loading tests were performed by the detonation of 25 kg ANFO explosive charge at 1.0 m standoff distance. Also, fire and blast-fire combined loading were tested using RABT fire loading curve. The test results are discussed in detail in the paper. The results can be used as basic research references for related research areas, which include protective design simulation under blast-fire combined loading.

A Study on the Efficiency of Container Ports in the Bay of Bengal Area (벵갈만 지역의 컨테이너항만 효율성 분석에 관한 연구)

  • Htet Htet, Kyaw Nyunt;Kim, Hyun Deok
    • Journal of Korea Port Economic Association
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    • v.36 no.1
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    • pp.41-58
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    • 2020
  • This study aims to investigate the technical efficiency of major container ports in the Bay of Bengal area and to study how certain factors influence the efficiency of container ports and terminals. The research is conducted on the four main container ports in the Bay of Bengal area, namely, Colombo Port in Sri Lanka, Chennai Port in India, Chittagong Port in Bangladesh, and Yangon Port in Myanmar. There are three input variables (quay length, storage area, and the number of cranes) and two output variables (throughput twenty-foot equivalent units and vessel calls) chosen for the process in this study. This paper evaluates the efficiency score of the defined variables and suggests implications for further improvement of the core competitiveness of the four selected ports. The findings indicate that Colombo Port is the most efficient on a technical scale, followed by Chennai Port, Yangon Port, and Chittagong Port. However, the slack and radial movement calculation results show that the inputs and outputs of the four ports need to be adjusted to be efficient and to reduce the amount of resources that are wasted. The results validate the adaptability of the improved data envelopment analysis algorithm in port efficiency analysis. The research findings provide an overview of the efficiencies of the selected container ports and can potentially affect the port management decisions made by policymakers, terminal operators, and carriers.