• Proceedings of KOSOMES biannual meeting
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• 2002.10a
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• pp.127-134
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• 2002

Ship operators are used to dredge anchor for the collision avoidance or safety of ship handling in a harbour or narrow channel. This paper clarifies the technique using tile anchor dredging known as a common sense for the seafarers. A mathematical model at low speed range has been established for the estimation of ship motion under the assumed environment , simulate the advance speed , and turning ability under the anchor dredging or not. The results shows good agreement with the conventional seamanship and their experiences as follows. Ahead speed used the anchor dredging is slower(speed reduction ratio:40%) than the normal ahead speed and the stopping distance is shorter (distance reduction ratio:40%)than the normal ahead distance without the anchor dredging. Turning speed used anchor dredging is slower(speed reduction ratio:72%)than the normal ahead speed and the tactical diameter is shorter(distance reduction ratio:24%)than the diameter by the normal turning without the anchor dredging.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.863-869
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• 2013

In this paper, we compared and analyzed for safety 1.2m rectangular anchor block and arch-type root anchor block. First, numerical analysis was performed three-dimensional nonlinear method by numerical model test using finite element analysis program "Visual FEA". Then, measure displacement of the surface of the earth after construct each anchor block at 14M electric pole and increase loads through field verification tests for safety evaluation.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10b
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• pp.72-74
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• 2000

인터넷을 효과적으로 검색하기 위하여 검색엔진을 많이 이용하고 있다. 그런데 문서의 키워드를 추출할 적에 지금까지는 Anchor Text를 염두에 두지 않았었다. Anchor Text는 사람이 직접 요약한 것이고(요약성), 하이퍼링크를 포함하는 웹 문서에 반드시 존재하므로(보편성) 그 하이퍼링크가 가리키는 곳의 문서의 키워드를 추출에 적합한 용도가 될 수 있다. 웹 그래프는 이러한 Anchor Text를 이용하여 키워드를 추출함으로써 문서와 문서간, 단어와 단어간의 관계(연관성)까지도 나타내 줄 수 있게 한 검색 엔진 시스템이다. 그러나 Anchor Text 자체가 본문의 내용이 아니고, Anchor Text를 작성한 사람에 따라 다르게 작성되며, 본문의 내용과 무관한 내용도 작성할 수 있다. 따라서 Anchor Text 자체를 어떠한 여과 없이 문서의 키워드로 받아들이긴 힘들다. 본 논문에서는 TFIDF를 통해 좀 더 정확성이 있는 키워드를 추출하였다.

• Journal of the Korean Society of Safety
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• v.29 no.1
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• pp.25-30
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• 2014

This paper deals with a numerical study on the deformation of a mono tendon anchor head. The anchor head is used to introduce the compression to concrete, and consists of wedges and a head. All kinematics, material and contact nonlinearity are included in the precise analysis of a mono tendon anchor head. A numerical study on a mono tendon anchor head is performed to investigate effects of friction and eccentricity of load by ABAQUS. From the numerical results, it is verified that the deformation of a mono tendon anchor head is affected by characteristics of materials, boundary condition between wedge and anchor head, eccentricity of load, etc.

• Journal of the Korean Geotechnical Society
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• v.24 no.11
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• pp.143-155
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• 2008

Ground anchors are classified depending on the kind of stress the grout is subjected to. If the grout material is subjected to tension then it is classified as tension anchor while when the grout material is subjected to compression it is classified as compression anchor. In this study a composite type anchor that possesses both the tension and compression mechanism was developed. For field tests, strain gauges were installed inside the anchor body in soft: soil. From the strain monitoring results, pull-out resistance mechanism that possesses both tension and compression strain was seen.

• Journal of Navigation and Port Research
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• v.38 no.6
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• pp.683-688
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• 2014

The vessel should prevent dragging anchor against the external forces by utilizing the anchor and secure the stability of it. A fundamental understanding on the embedding motion and holding power of the anchor is necessary to perform the safe operating of anchor work. In this study, the embedding motion and holding power of the anchor according to an initial position in an experimental tank of 6m long in sand are tested by using two types of different anchor models(ASS and AC-14), which are generally applied to the commercial vessel nowadays. The anchor flukes seem to rotate and to be embedded into soil up to the maximum depth and maintaining a constant depth in case of the same direction and perpendicular to the towing direction, regardless of the form of an anchor. In case of the opposite direction to the towing direction, it is noted that the coefficient of holding power becomes smaller than the other initial positions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.4
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• pp.289-298
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• 2022

Sea anchor for fishery is commonly used in jigging fishery and purse seine. The study of sea anchor was studied for improvement of opening efficiency and drag by changing the type of shape and the diameter of vent. However, standard specification of sea anchor is not set and has not been studied for underwater stability. Therefore, this study aimed to improve underwater stability of sea anchor by changing a vent diameter and weight of sinker. The experiment was conducted in flume water tank. The experiment model of sea anchor was made from actual model of sea anchor which is used in fishery by similarity law. The model of sea anchor was designed to different types of vent diameter and weight of sinker in different current speed. The value of movement of side to side (X-axis), drag of sea anchor (Y-axis) and movement of up and down (Z-axis) was measured for 30 seconds. Each value of X, Y, Z-axis was analyzed through t-test and ANOVA analysis to verify that each value had a significant difference according to the difference compositions. There was correlation between the movement of X-axis and Z-axis. The drag of sea anchor was stronger as the current speed increased. However, the larger the vent diameter, the weaker the drag. From the result of the standard deviation, the movement of X-axis was inversely proportional to the vent diameter. However, movement of Z-axis was larger as the weight of sinker was the heaviest or lightest from the result of the standard deviation. These results suggest that the sea anchor should be combined with proper size of the vent diameter and the weight of sinker to improve the stability.

• Journal of the Korean GEO-environmental Society
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• v.13 no.11
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• pp.5-10
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• 2012

Many electric poles in the softground have been collapsed due to external load. In this study, several tests were performed with variation of numbers and depths of anchor blocks to find effects of anchor blocks on stability of concrete electric poles through earth pressure and displacement analysis. 1.50m depth of anchor block seems appropriate among three kinds of depths. The 2.25m depth of anchor block makes larger displacement due to disturbance caused by excessive excavation. The deeper anchor block, the less earth pressure of passive zone, an active earth pressure gets larger. When two anchor blocks were installed, displacement at top pole decreased 43.8% and 55.6% at ground when 1 anchor block was installed.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.517-520
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• 2005

The embedded suction anchor(ESA) is and anchor that is driven by a suction pile. The cross-sectional shape of the ESA anchor is circle. Its diameter is the same as that of the suction pile that is used to drive it into the seafloor. For the installation, the anchor is attached to the tip of the suction pile and then driven as a unit with the pile by and applied suction pressure. Once the ESA anchor reaches the desired depth, the pile is retrieved by applying a positive pressure. Finally, only the ESA anchor remains in the soil layer. This paper presents the results of centrifuge model tests to investigate ESA pullout capacity. The main parameters that have effects on the pullout capacity of ESA may include g-level, embedded depth, direction of loading, and loading point. The results of tests show that the pullout loading capacities increase as the loading point shift toward the tip of the anchors for a given loading direction. They also indicate that the loading point associated with the maximum pullout loading capacity is located at approximately 67 percent of the anchor length from the top for the horizontal load.

• Journal of Ocean Engineering and Technology
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• v.27 no.1
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• pp.59-66
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• 2013

A suction anchor is one of the most popular anchors for deepsea floating systems. An anchor used for catenary mooring is predominantly under a horizontal load. In this study, the behavior of a suction anchor installed in cohesionless soil was investigated when the anchor was mainly subjected to a horizontal load induced by a catenary line. In order to study the behavior of the suction anchor, 3D FEM analysis models were developed and analyzed. Depending on the location of the load (padeye), the ultimate horizontal load was monitored. The distributions of the reaction forces around the anchor induced by the seabed were analyzed using the circumferential stress to understand the behavior of the suction anchor under a horizontal load.