• Title/Summary/Keyword: Splash

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Oil Carrier, Development of on Optimized Anti-Splash Device Model for COT Vent Pipe (유조선, COT Vent Pipe용 Anti-Splash Device 최적 모델 개발)

  • Na, Ok-kyun;Jeon, Young-Soo;Park, Sin-kil;Kim, Jong-Ho
    • Special Issue of the Society of Naval Architects of Korea
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    • 2015.09a
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    • pp.50-55
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    • 2015
  • Application of newly conceptualized Anti-Splash Devices designed for COT vent pipes were studied on a P/V valve located on the upper deck of an oil carrier vessel. Anti-Splash devices are used in the shipbuilding industry in order to avoid oil overflow and spray accidents caused by excess pressure and vacuum condition in the cargo oil tanks. These conditions are caused by the transverse and longitudinal sloshing forces that arise from ship motion during sea voyages. The main issue with existing Anti-Splash device model is flux at the outlet of the Anti-Splash Device, and so, new conceptual models for the Anti-Splash device were developed and compared to existing Anti-Splash device model using CFD analysis. Transient analysis was used to capture the flow and velocity of each model and a comparative analysis was performed between old and new-concept models. This data was used to determine the optimal design parameters in order to develop an optimized Anti-Splash Device. A Factory acceptance test was performed on the new-concept models in order to verify the performance and efficiency against their design requirements and other criterion. The final step performed was to apply the optimized Anti-Splash Device models for COT vent pipes to an actual vessel and verify performance through a seawater cargo operation during a sea voyage as per the ship owner's request. The patent for the aforementioned device was obtained by the Korean Intellectual property Office dated Dec. 18th,2014.

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Implementing stream processing functionalities of Splash (Splash의 스트림 프로세싱 기능 구현)

  • Ahn, Jaeho;Noh, Soonhyun;Hong, Seongsoo
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2019.01a
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    • pp.377-380
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    • 2019
  • To accommodate for the difficult task of satisfying application's system timing constraints, we are developing Splash, a real time stream processing language for embedded AI applications. Splash is a graphical programming language that designs applications through data flow graph which, later automatically generates into codes. The codes are compiled and executed on top of the Splash runtime system. The Splash runtime system supports two aspects of the application. First, it supports the basic stream processing functions required for an application to operate on multiple streams of data. Second, it supports the checking and handling of the user configurated timing constraints. In this paper we explain the implementation of the first aspect of the Splash runtime system which is being developed using a real time communication middleware called DDS.

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A Measurement of Splash Erosion Under Natural Rainfall (야외(野外)에서 Splash Erosion 측정(測定)에 관한 연구(硏究))

  • Shin, Jae-Sung;Ko, Mun-Hwan;Im, Jeong-Nam
    • Korean Journal of Soil Science and Fertilizer
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    • v.14 no.3
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    • pp.104-109
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    • 1981
  • The experiment was designed to measure splash erosion and to investigate the relationships between soil detachment, kinetic energy and C factor at various soils and crops under the natural rainfall, using the modified Ellison cup. The results obtained were as follows: 1. Splash erosion increased as the texture was coarser, reaching a maximum amount in loamy sand of 12.6ton/10a/year, 9.7ton for loam, 9.0ton for sandy loam, and 7.0ton for clay loam. 2. Splash erosion positively related to kinetic energy ($EI_{30}$) but negatively to K value. 3. A considerable relationship between splash erosion and kinetic energy was observed under coverage less than 50%; however, it decreased with increasing canopy resulting in no relation over 90% coverage. The amount of soil detachment by natural rainfall ranged from 10 to 15ton/10a at various cropping systems. 4. The particle size distribution of splashed soil was similar to that of original one and fine sand($250-100{\mu}$) marked the highest detachment and splash.

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A study on the risk factors associated with blood splash in slaughtered cattle (도축우의 근출혈 유발 인자에 관한 연구)

  • Ku, Kyung-Nyer;Byun, Byung-Lae;Shim, Hang-Sub;Lee, Ho-Seung;Kim, Kyung-Suk;Woo, Jong-Tae
    • Korean Journal of Veterinary Service
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    • v.32 no.3
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    • pp.287-292
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    • 2009
  • This study was conducted to analyse risk factors which can influence on blood splash in slaughtered cattle in D slaughterhouse located in Gyeonggi province in 2008. A total of 13,056 cattle were studied by several risk factors such as species, gender, body weight, meat grade, weather (temperature), transport distance, lairaging time, moving time, mixing cattle from different sources. As the result of analysis, the total mean of blood splash was 0.70% and the rate was highest (0.94%) in castrated Hanwoo. The heavier body weight, the higher blood splash rate. The farms which have had more than one experience of blood splash tend to have high grade in meat quality. As a weather factor, the rate in summer season was lower than in winter season. It increased as transport distance getting longer and decreased when the lairaging time was 2~5 hours. We could know many risk factors strongly related with the occurrence of blood splash from this study.

Study on the Corrosive Characters of Carbon Steel in the Marine Splash Zone

  • Zhu, Xiangrong;Han, Bing
    • Corrosion Science and Technology
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    • v.2 no.1
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    • pp.26-29
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    • 2003
  • This study determined that the four corrosive characters of carbon steel in the marine splash zone (MSZ) in China's four sea areas. It has a range and a corrosion peak value. The rust in the MSZ plays the role of "depolarizer" in the cathodic process of corrosion. The growth law of the rust layer in MSZ has a character of "annual ring". In addition the reasons causing serious corrosion of carbon steel in the marine splash zone has been discussed in this paper.

A Study on Application of Finite Element Method to the Impact test for the Safety of the Splash Guard of a CNC Machine Tool (CNC 공작기계 스프레쉬 가드의 안전성을 위한 충격 시험에 대한 유한요소법 적용에 관한 연구)

  • Kim, Tae Won;Choi, Jin Woo
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.5
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    • pp.782-788
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    • 2013
  • This study addresses the issue of safety of the splash guard of a computer numerical control (CNC) machine tool at the design stage. As an impact test for evaluating safety requirements such as strength under the safety regulation is an expensive and iterative task, it is necessary to develop a new method to minimize the task of the impact test for development of the machine tool. In this study, explicit finite element method was adopted for replacement of the impact test of the splash guard of a machine tool at the design stage. A finite element model was developed for implementing the impact test on an actual vertical CNC lathe and then produced the analysis including plastic strain and deformation to enable the safety of its splash guard to be determined. The analysis results demonstrated that the finite element method can be applied to safety evaluation for design of the splash guard of a CNC machine tool.

Rate-Controlled Data-Driven Real-Time Stream Processing for an Autonomous Machine (자율 기기를 위한 속도가 제어된 데이터 기반 실시간 스트림 프로세싱)

  • Noh, Soonhyun;Hong, Seongsoo;Kim, Myungsun
    • The Journal of Korea Robotics Society
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    • v.14 no.4
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    • pp.340-347
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    • 2019
  • Due to advances in machine intelligence and increased demands for autonomous machines, the complexity of the underlying software platform is increasing at a rapid pace, overwhelming the developers with implementation details. We attempt to ease the burden that falls onto the developers by creating a graphical programming framework we named Splash. Splash is designed to provide an effective programming abstraction for autonomous machines that require stream processing. It also enables programmers to specify genuine, end-to-end timing constraints, which the Splash framework automatically monitors for violation. By utilizing the timing constraints, Splash provides three key language semantics: timing semantics, in-order delivery semantics, and rate-controlled data-driven stream processing semantics. These three semantics together collectively serve as a conceptual tool that can hide low-level details from programmers, allowing developers to focus on the main logic of their applications. In this paper, we introduce the three-language semantics in detail and explain their function in association with Splash's language constructs. Furthermore, we present the internal workings of the Splash programming framework and validate its effectiveness via a lane keeping assist system.

Mean viscous drift forces on a fixed vertical cylinder in waves and currents (파랑과 조류에 의한 고정된 수직 실린더 구조물에 작용하는 평균 점성 표류력)

  • Shin, Dong Min;Kim, Yuncheol;Moon, Byung Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.521-527
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    • 2020
  • In offshore structures, the mean viscous drift force due to drag is considered to be a design part that has not been considered until recently. In particular, it is most important to calculate the drift force acting on a vertical cylinder considering both waves and currents in the low frequency region. This paper presents a process for deriving analytical solutions for the drift forces acting on a fixed vertical cylinder considering waves and currents. The area of the cylinder was considered by dividing it into a splash zone above the free surface and a submerged zone below the free surface. The presence of waves is considered only in the Splash Zone, and in the case of waves and currents, the equations were obtained for both the splash and submerged zones. The results show that drift forces occur due to the significant viscous effects in both the splash zone and the submerged zone. Therefore, the analytical solutions derived in this study can be used to calculate the drift force using the given design variables and form a theoretical basis for judging whether the magnitude of the drift force in each case has a dominant influence within a specific physical range.

Viscous Mean Drift Forces on a Floating Vertical Cylinder in Waves and Currents (파랑과 조류에 의한 부유식 수직 실린더 구조물에 작용하는 평균 점성 표류력)

  • Shin, Dong Min;Moon, Byung Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.503-509
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    • 2020
  • In offshore floating structures, the viscous mean drift force due to drag is considered a design part that has not been considered until recently. In this paper, an analytical solution for the viscous mean drift forces on a floating vertical cylinder considering the waves and currents was obtained. The area was considered by dividing it into a splash zone above the free surface and a submerged zone below the free surface. In the case of waves, only the splash zone was considered; in the case of waves and currents, equations were obtained in both the splash zone and the submerged zone. The RAO results of previous studies were used to compare the calculated results with the drift forces acting on the fixed cylinder. Except for the case in only waves in the splash zone, the viscous mean drift force acting on the floating cylinder was larger than the drift force acting on the relatively fixed cylinder in most frequencies. In particular, the increase was greater when the currents were considered to be more important. Therefore, these results provide the inference for the viscous drift force due to drag in the design of floating offshore structures.

Corrosion Behaviour of DH36 Steel Used for Oil Platform in Splash Zones

  • Liu, J.G.;Li, Y.T.;Hou, B.R.
    • Corrosion Science and Technology
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    • v.14 no.4
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    • pp.190-194
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    • 2015
  • The splash zone is the most corrosive area of the marine environment, and the corrosion of steel structures exposed in this area is a serious concern. DH36 steel is one of most commonly used steels for offshore oil platforms in China, and its corrosion behaviour in splash zones was studied in this paper. Polarization curves were obtained from the corroded steel exposed in this area while the morphologies and rusts of the rust steel were characterized using scanning electron microscopy and X-ray diffraction. Double rust layers were formed in the splash zone. The inner layer contained magnetite and fine flaky lepidocrocite, and the outer layer was composed of accumulated flaky lepidocrocite and a small amount of goethite. In the wet period, the iron dissolved and reacted with lepidocrocite, and magnetite appeared, while the magnetite was oxidized to lepidocrocite again during the dry period. Electrochemical reduction and chemical oxidization cycled in intermittent wetting and drying periods, and magnetite and lepidocrocite were involved in the reduction reaction, leading to serious corrosion.