• 제목/요약/키워드: Draft depth

검색결과 94건 처리시간 0.026초

Modelling of Oil Boom Failure using the Fluent (Fluent를 이용한 오일 붐 누유 모델링)

  • 배석한;정연철
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 한국항해항만학회 2003년도 춘계공동학술대회논문집
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    • pp.171-178
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    • 2003
  • When oil is spilled at sea, the oil boom is commonly used to tackle the movement and spreading of oil in an early stage of oil spill combat. But, the retaining capability of oil boom is affected by various factors, such as water velocity, viscosity, and density of oil, water depth, oil volume and the length of boom draft. In this study, computer modeling was peformed to investigate how these factors influence the oil retaining process. The Fluent, most popular one of many CFD(computational fluid dynamics) programs is chosen for modelling and modelling results were verified using the empirical data. It is expected that results of this study will be useful data for oil boom designer and oil spill response commander.

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A study on the turning-motion of T/S SAEBADA in shallow water (실습선 새바다호의 천수역 선회운동에 관한 연구)

  • KIM, Su-Hyung;LEE, Chun-Ki
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • 제55권3호
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    • pp.273-283
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    • 2019
  • The authors has predicted the maneuvering characteristics of a fishing vessel in deep water using Kijima's empirical formula in a previous study. Since the Kijima's empirical formula was developed by a regression analysis of merchant vessels which have dimensions ($C_b$, L/B, etc.) that are different from those of fishing vessels, it was possible to make a prediction approximately even with inaccurate estimation. In this study, the authors estimated the turning-motion characteristics of a model ship of fisheries training ship in shallow water based on the results of its previous study. The turning-motion characteristics of the model ship in shallow water was found out through quantitative analysis according to the water depth to ship draft ratio (H/d). In conclusion, the turning-motion characteristics of the model ship had significant changes immediately after an H/d 1.5, and this result will be helpful for sailing in shallow water.

Genome Wide Analysis of the Potato Soft Rot Pathogen Pectobacterium carotovorum Strain ICMP 5702 to Predict Novel Insights into Its Genetic Features

  • Mallick, Tista;Mishra, Rukmini;Mohanty, Sasmita;Joshi, Raj Kumar
    • The Plant Pathology Journal
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    • 제38권2호
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    • pp.102-114
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    • 2022
  • Pectobacterium carotovorum subsp. carotovorum (Pcc) is a gram-negative, broad host range bacterial pathogen which causes soft rot disease in potatoes as well as other vegetables worldwide. While Pectobacterium infection relies on the production of major cell wall degrading enzymes, other virulence factors and the mechanism of genetic adaptation of this pathogen is not yet clear. In the present study, we have performed an in-depth genome-wide characterization of Pcc strain ICMP5702 isolated from potato and compared it with other pathogenic bacteria from the Pectobacterium genus to identify key virulent determinants. The draft genome of Pcc ICMP5702 contains 4,774,457 bp with a G + C content of 51.90% and 4,520 open reading frames. Genome annotation revealed prominent genes encoding key virulence factors such as plant cell wall degrading enzymes, flagella-based motility, phage proteins, cell membrane structures, and secretion systems. Whereas, a majority of determinants were conserved among the Pectobacterium strains, few notable genes encoding AvrE-family type III secretion system effectors, pectate lyase and metalloprotease in addition to the CRISPR-Cas based adaptive immune system were uniquely represented. Overall, the information generated through this study will contribute to decipher the mechanism of infection and adaptive immunity in Pcc.

A study on estimating the main dimensions of a small fishing boat using deep learning (딥러닝을 이용한 연안 소형 어선 주요 치수 추정 연구)

  • JANG, Min Sung;KIM, Dong-Joon;ZHAO, Yang
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • 제58권3호
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    • pp.272-280
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    • 2022
  • The first step is to determine the principal dimensions of the design ship, such as length between perpendiculars, beam, draft and depth when accomplishing the design of a new vessel. To make this process easier, a database with a large amount of existing ship data and a regression analysis technique are needed. Recently, deep learning, a branch of artificial intelligence (AI) has been used in regression analysis. In this paper, deep learning neural networks are used for regression analysis to find the regression function between the input and output data. To find the neural network structure with the highest accuracy, the errors of neural network structures with varying the number of the layers and the nodes are compared. In this paper, Python TensorFlow Keras API and MATLAB Deep Learning Toolbox are used to build deep learning neural networks. Constructed DNN (deep neural networks) makes helpful in determining the principal dimension of the ship and saves much time in the ship design process.

Three-Dimensional Wave Control and Dynamic Response of Floating Breakwater Moored by Piers (말뚝계류된 부방파제의 공간파랑제어 및 동적거동에 관한 연구)

  • 김도삼;윤희면
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • 제14권3호
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    • pp.183-191
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    • 2002
  • In general, the salient features of the floating breakwater have excellent regulation of sea-water keeping the marine always clean, up and down free movement with the incoming and outgoing tides, capable of being installed without considering the geological condition of sea-bed at any water depth. This study discusses the three dimensional wave transformation of the floating breakwater moored by piers, and its dynamic response numerically. Numerical method is based on the boundary integral method and eigenfunction expansion method. It is known that pier mooring system has higher absorption of wave energy than the chain mooring system. Pier mooring system permit only vertical motion (heaving motion) of floating breakwater, other motions restricted. It is assumed in the present study that a resistant force as friction between piers and floating pontoon is not applied far the vertical motion of the floating breakwater. According to the numerical results, draft and width of the floating breakwater affect on the wave transformations greatly, and incident wave of long period is well transmitted to the rear of the floating breakwater, And the vertical motion come to be large for the short wave period.

A Development of Hanbok Jeogori Pattern from Virtual Garment Simulation - With a Focus on Women in their 50s - (가상착의를 활용한 한복 저고리 원형설계의 기초연구 - 50대 중년여성을 중심으로 -)

  • Lim, Ji-Young;Lee, Hae-Young
    • Fashion & Textile Research Journal
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    • 제14권4호
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    • pp.607-613
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    • 2012
  • This study develops a Hanbok Jeogori pattern for middle-aged women with a 3D virtual-twin and virtual-garment simulation system. The including criteria for subjects in this study was a focus on women in their 50s, and a total of 345 females satisfying them were enrolled for 3D virtual model. Comparative Jeogori pattern, Baik & Choi's(2004) pattern, was selected for the development of Jeogori pattern. The results were: first, a new Jeogori pattern considerate of middle-aged women was developed. The basic numerical formula were: Front and back bust girth B/4+1.5, armhole depth B/4, sleeve width B/4, goedae width B/10-1.5 and git width 5.5. Second, according to the results of the new Jeogori patterns appearance evaluation, the new Jeogori pattern scored higher than the existing pattern in silhouette and ease amount, this confirmed that the new Jeogori pattern is appropriate for middle-aged women. Virtual models of production through data from 3D body scan, pattern draft, and virtual garment digital program were applied to a prototypic design method to enhance the fitness of ready-made Hanbok garments. This study serves as important basic data for ensuing studies that may utilize 3D Virtual Garment Simulation System with 2D patterns and for the future 3D Pattern Production Program development of Hanbok patterns.

A Development of the Uniform Pattern for Obese Junior-High School Girls from Virtual Garment Simulation (가상 착의 시스템에 의한 비만 여중생의 교복 원형 개발)

  • Lim, Ji-Young
    • The Research Journal of the Costume Culture
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    • 제19권2호
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    • pp.245-254
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    • 2011
  • The purpose of this study was to develop uniform pattern of obese junior-high school girls by using the virtual twin and 3D virtual garment simulation system. The results were as follows; first, by using 3D virtual garment simulation, new uniform pattern considered obese junior-high school girls was development. The basic numerical formula were as follows; bust girth=B/2+2.5, armhole depth=B/4, front waist girth=W/4+1.8, back waist girth=W/4+1, front hip girth=H/4+1, back hip girth=H/4+1, chest width=chest width+1.5, back width=back width+1 and back neck width 8cm. Second, according to the results of the new uniform pattern's appearance evaluation, it estimated more highly than existing pattern in silhouette and ease amount, confirming that new uniform pattern is appropriate for the obese junior-high school girls. Also, new uniform pattern was evaluated to allow proper space length of bust, waist, abdomen and hip. Virtual models production through 3D body scan data, pattern draft and virtual garment digital program were applied to prototypic design method so as to enhance the fitness of ready-made garments. This study is expected to serve as one of important basic data for ensuing studies that may utilize 3D virtual garment simulation system with 2D patterns, and also for future 3D pattern production program development.

Development of Job Satisfaction Scale for Clinical Nurses (임상간호사의 직무만족 측정도구 개발)

  • Lee, Byoung-Sook;Eo, Yong-Sook;Lee, Mi-Aie
    • Journal of Korean Academy of Nursing
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    • 제48권1호
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    • pp.12-25
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    • 2018
  • Purpose: This study was performed to develop the Job Satisfaction Scale for Clinical Nurses (JSS-CN) and verify its validity and reliability. Methods: A preliminary 42-item version of the JSS-CN was developed through literature reviews and in-depth interviews. The draft scale was developed using thirty-seven items selected following content validity evaluation. Finally, thirty-three items with response options on a 5-point Likert scale were selected based on internal consistency reliability and construct validity. Subsequently, the test-retest reliability and convergent validity of the JSS-CN were verified. Results: Six factors, namely, recognition from the organization and professional achievement, personal maturation through the nursing profession, interpersonal interaction with respect and recognition, accomplishment of accountability as a nurse, display of professional competency, and stability and job worth, were identified, which explained 59.7% of the total variance. The JSS-CN's Cronbach's ${\alpha}$ for the total scale was .95, and the intra-class correlation coefficient was .90. The correlation coefficient between the scores of the JSS-CN and Slavitt's scale was .75, and that between the JSS-CN and job performance was .53. Conclusion: Results showed that the JSS-CN has good reliability and validity. Therefore, it is concluded that the JSS-CN could be a useful tool for the measurement of the job satisfaction of clinical nurses in Korea.

Measurement of Maneuverability in the Restricted Area by Numerical Model Ship (수치 모형선에 의한 제한수역에서의 조종성능 측정)

  • Park, Byung-Soo;Kim, Jong-Hwa;Kim, Cheog-Su
    • Journal of the Korean Society of Marine Environment & Safety
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    • 제15권4호
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    • pp.363-367
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    • 2009
  • The ship maneuverability is changed by the effects of the bank cushion and the squat in the restricted water area. It is difficult to test the ship maneuverability by the real ship in the restricted water area because of ship's safety. In this study, a numerical model ship was used to simulate the ship's motion and to get information about the bank cushion and the squat in the restricted water area. The less apart from the quay the ship ran, the more ship's heading changed. The greatest change of ship's heading was $22.37^{\circ}$ when a ratio of the length between ship and quay to ship's breadh(=D/B) was 0.2. The squat of the ship was greater in shallower water and at faster speed. The greatest squat was 0.29m when a ratio of water depth to ship's draft(H/d) was 1.25 and ship's speed was 8 knots, the reduced speed was found to be the most important factor in the shallow water area for safety of the ship.

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Marine traffic survey to improve safety of vessel traffic at Busan South Port (부산남항 선박통항 안전성 향상을 위한 해상교통량 조사)

  • Kim, Seok-Jae;Park, Moon-Gap;Lee, Yoo-Won
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • 제47권4호
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    • pp.428-434
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    • 2011
  • To establish a vessel safety management system for improving the safety of vessel's traffic and preventing vessel's traffic accidents, the state of marine traffic in the Busan South Port was investigated and analyzed as preliminary survey of the countermeasures. As a result of the study, there are 1,158 vessels in a day, 48 vessels in an hour, and the maximum traffic is about 118 vessels between 16:00 and 17:00 hours everyday, which requires to establish and operate a traffic control system necessarily for ensuring vessel's traffic safety. Furthermore, passages of tanker, passenger ship, cargo vessel and government vessel showed to sail along main traffic lane to be obtained enough sea depth at the survey area. However, passages of fishing vessel and launch showed to sail freely at all survey area owing to outstanding maneuverability and a shallow draft. Some vessels of launch sailed along main traffic lane, but other vessels crossed to sail it. The passages to cross main traffic lane is higher the risk of collision. Therefore, safety measures are urgently needed for the operation of the Busan South Port management system and the prevention of marine pollution.