• 한국수산과학회지
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• 제36권6호
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• pp.743-748
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• 2003

An oil boom was set up in order to contain diffused oil from spills and for the retrenchment of damage caused by oil Pollution. Therefore, the oil boom anchor needed proper holding power to endure high resistance from flowing streams and to secure the oil boom around the spill, and must dredge directly into the seabed when it is dropped and block oil outflow immediately. This study investigated the holding power of the danforth anchor and the coastal fishing vessel anchor used for oil booms in the KMPRC (Korea Marine Pollution Response Corporation). For each type, a 30 kg and 20 kg anchor were used. The holding power of the danforth anchors were measured by dropping both weights 10 times. However the coastal fishing vessel anchors were dropped only 5 times each, because no substantial differences were found between drops. In the results of the danforth anchors, an anchor awoke occurred in 2 drops of the 30 kg anchor and in 4 drops of the 20 kg anchor, wherein there was no holding power to be measured. With exception to the anchor awoke cases, the maximum holding power of the danforth 30 kg and 20 kg anchors was 250-520 kg and 123-233 kg, respectively. In the case of the coastal fishing vessel anchors of 30 kg and 20 kg, throughout the experiment, there was no occurrence of an anchor awoke. For the 30 kg and 20 kg anchors, the maximum holding power was measured to be 209-230 kg and 155-170 kg, respectively. Therefore, the holding power of the coastal fishing vessel anchor was shown to be much poorer than that of the danforth anchor. However, the holding power of the danforth anchor was very unstable. Due to the occurrences of anchor awoke, there was no holding power and the measurement value of maximum holding power showed too much variation among the drop tests. Also, after the maximum holding power was achieved, anchor awoke occurred easily. In the case of the coastal fishing vessel anchor was much more stabile, because there was no anchor awoke and no instance where holding power failed. Also the maximum holding power was reached quickly and almost no variation occurred among the drop tests.

• 수산해양기술연구
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• 제27권2호
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• pp.97-104
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• 1991

일반적으로 선박에서 많이 사용하고 있는 Hall형묘와 묘쇄의 파주력계수를 구하기 위하여 모형실험을 실시한 결과를 요약하면 다음과 같다. 1. 저질 뻘에서 착의 최대파주력계수는 4.05였고, 묘쇄의 파주력계수는 0.75였다. 저질 모래에서의 묘의 최대파주력계수는 3.95였고, 묘쇄의 파주력계수는 0.66였다. 저질 자갈에서 묘의 최대파주력계수는 3.61이었고, 묘쇄의 파주력계수는 0.72였다. 2. 모형묘와 착쇄의 파주력계수는 저질에 따라서 상용파주력계수의 0.3~0.6배 였고, 안전파주력계수와는 거의 같은 경향을 나타내었으며, 다만 자갈에서는 안전파주력계수보다 1.4~1.8배 높았다. 3. 풍력과 저질에 따른 각 종 파주력 곡선도를 작성하여 한계파주력을 설정하여 활용하면 선박의 안전운용에 도움이 되리라 기대된다.

• 한국항해항만학회지
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• 제39권1호
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• pp.1-6
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• 2015

본 연구에서는 해군 함정에서 운용하고 있는 묘의 파주력과 파주계수에 대한 계산이 단순하게 특정한 값만을 적용하고 있다는 한계를 인식하고, 이러한 한계를 극복하기 위해 기존 문헌연구 자료와 묘 제작사, 연구기관, 학계의 여러 실험결과를 바탕으로 함정이 보유한 묘의 형태별 파주력과 파주계수를 비교 분석하였다. 함정에서 사용 중인 대표적인 묘의 형태별 파주력 및 파주계수를 비교분석한 결과 AC-14형 묘는 ASS형 묘나 U.S. Navy Standard형 묘에 비해 큰 파주력을 가지며 이는 묘의 경량화를 가능케 하여 조함의 용이성에 도움이 됨을 확인하였고, U.S. Navy Standard형 묘는 중량의 변화에 파주계수의 값이 민감하게 반응하지 않는 특성을 확인하였으며, Danforth형 묘는 파주계수가 중량에 반비례한 특징을 확인하였다. 또한 묘를 운용할 때 유의하고 보완할 사항을 알기쉽게 정리하였다. 본 연구의 결과는 묘를 운용하는 함정 승조원에게 파주력과 파주계수와 관련하여 신뢰성 있는 이론적 근거를 제공하고 보다 안전하게 묘박을 할 수 있도록 하는데 기여를 할 것으로 기대된다.

• 수산해양기술연구
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• 제54권1호
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• pp.25-31
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• 2018

In this study, the differences of holding power according to the shape and weight distribution of concrete weight used in shellfish shell fishery were investigated through the experiments. To investigate the differences in shape, five bar-shaped concrete weights with the same length and different cross-sectional shapes were produced. The sectional shape of each weight was square, triangle, circle, small cross, and large cross (SQ, TR, CI, CR-S, CR-L). Ten rectangular parallelepiped weights with different bottom area and cross-sectional area were produced. To investigate the differences by the weight distribution, the holding power on the square model (SQ) with six 50 g weights at different positions was investigated. All the holding power was obtained by measuring the tensile force generated when the concrete weight was pulled at a constant speed on the sand. As a result, there were no differences in holding power between the ten rectangular weights. However, the experiment on weights with different cross-sectional shapes showed differences in holding power. The holding power was higher in the order of CR-L > CR-S > CI > TR > SQ. In the weight distribution test, the holding power was higher as the front side of the weight was heavier. Generally, the frictional force is the same even if the shape is different, when two objects have the same value in the weight and the roughness. On the other hand, it seems to have a large impact when the shape of the bottom is deformed in the course of pulling the object. Particularly, the larger the degree of protrusion like cruciform weights, the more the holding power increased while deeply digging the bottom. It is also likely that the holding power increases as the front weight increases.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 제 25회 정기총회 및 추계학술발표회
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• pp.151-158
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• 2000

1. Instruction. 2. Investigation about holding power in Da san mooring area. 3. Weather condition in Da san anchorge. 4. Calculation of Externer power. a. Calculation of Container ship' holding power in mooring. 6. Comparison of Container ship' External power and holding power. 7. Conclusion.

• 한국실내디자인학회논문집
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• 제20권4호
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• pp.174-182
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• 2011

This study analyzed visitors' behaviors in the viewpoint of Attraction Power and Holding Power of exhibits on the basis of exhibition layout of real science museums. Through the analysis, the study grasped efficiency of analysis index and exhibition environment elements which might have an effect on planning the exhibition space of a large-scale museum and producing detailed ranges of exhibition. The main indicators used are: 1. Attraction Power: it indicates the relative incidence of people who have stopped in front of an object/exhibit during the exhibition tour. It is calculated by dividing the number of people who stop by the total number of people who have visited the museum or gallery. 2. Holding Power: it measures the average time spent in front of an information/communication element. It is calculated by dividing the average time of stay by the time "necessary" to read an element. As a result of analyzing the exhibition areas of National Science Museum (Daejeon) and National Museum of Emerging Science and Innovation(Tokyo), the Holding Power was found to be relatively lower than the Attracting Power. This means that 3.5 out of 10 visitors stop in front of the exhibit in 6 exhibition areas, and among these, only 1/10 is used when compared to the user required time of the exhibits. In other words, like the method of deriving an analysis index, the stage of viewing can be categorized as Attracting Power and Holding Power, and because the stage from Attracting Power to the stage of Holding Power are strongly linked, it shows that it is not easy to display a meaningful result. Except, the general distribution of Attracting Power was shown to be high from the entrance area of the exhibition hall based on the standard of viewing sequence. Also, the Holding Power became sequentially lower according to the sequence of exhibition viewing and displayed a meaningful interrelationship with the distribution ratio of island exhibits. In the case of island exhibition method, it is less influenced by the movement flow of visitors when compared to the wall type method of exhibition and can be understood as an exhibition method that provides spatial chances enabling stopping and viewing.

• 대한조선학회논문집
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• 제48권2호
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• pp.183-187
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• 2011

As larger the commercial vessel is, and rougher the marine environment becomes nowadays, drag embedment type anchor (DEA) of more stable performance and higher holding power is requested to be applied on the vessel. But, the performance of DEA has not become well known to academy and industries so far, that the basic study of DEA performance and holding force for the development of new DEA of higher performance is insufficient that required. In this paper, three types of same holding category DEA model (HALL, AC-14, POOL-N, scale 1/10), which are generally applied on the commercial vessel nowadays, were tested by being horizontally dragged on the test tank, on which sand was being floored with sufficient depth, and measured the holding force of each anchor simultaneously using load cell and D/A converter. With the test results, the embedding motion was analyzed to have three different stages and the holding force of each anchor was analyzed with respect to the anchor geometry, such as shape and weight of each type of anchors, and final embedding depth.

• Journal of Biosystems Engineering
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• 제25권5호
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• pp.391-398
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• 2000

This study was performed to analyze the holding pace and decision factors of tractor in Korea and Japan, which probably should be used for making master plan of agricultural mechanization. The logistic function is used for holding pace estimation of tractor, and log-log function for analysis of decision factors. The results of this study are as follows: First, the increasing rate of the total amount of holding tractor power in Korea has been over that in Japan during 1980∼、94 which is now, however, under Japan. So, it could be forecasted that the per tractor holding power in Japan will increase continuously, and will be over 30PS in the short run. Second, the most important one of decision factors to support tractor demand is agricultural income in Korea, but on the other hand Non-Agricultural Income in Japan. From these, the fast increase of total amount of holding power of tractor in Korea could not expected, because Korea Agriculture has some difficulties to increase Agricultural Income. There are differences on the holding pace and decision factors of tractor between Korea and Japan, therefore, the plan of agricultural mechanization should be made in accordance with self-features.

• 한국실내디자인학회논문집
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• 제20권1호
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• pp.165-172
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• 2011

Visitors' behaviors within an exhibition space are a substantial means to grant spatial arrangement and validity of exhibits. Therefore, the study analyzed visitors' behaviors in the viewpoint of attraction power and holding power of exhibits on the basis of exhibition layout of real science museums. Through the analysis, the study grasped efficiency of analysis index and exhibition environment elements which might have an effect on planning the exhibition space of a large-scale museum and producing detailed ranges of exhibition. The main indicators used are: 1. Attraction power: it indicates the relative incidence of people who have stopped in front of an object/exhibit during the exhibition tour. It is calculated by dividing the number of people who stop by the total number of people who have visited the museum or gallery. 2. Holding power: it measures the average time spent in front of an information/communication element. It is calculated by dividing the average time of stay by the time "necessary" to read an element. As a result, It was expected that attraction power and holding power of exhibit would be increased when moving line of seeing was inductive. However, when the traffic movements of seeing was inductive, repetitive seeing of exhibit was almost never realized and visitors had a strong tendency which viewed on their way of moving without viewing on their way of stopping. On the other hand, it may mean that density of exhibit is low or size of exhibition space is small that most of exhibits within exhibition space have high attraction power and holding power. As Gwacheon National Science Museum, when a museum is composed of many large-scale exhibit halls, it should be formed by separating the main moving line of seeing from the optional moving line of seeing through visitors' natural choice of exhibit and proper inducement of moving line of seeing. In such structure, exhibition environment of the main moving line has an effect on attraction of exhibit and the use of optional moving line acts as a factor to increase attraction. In addition, it is thought that attribute of exhibit and proper arrangement of rest space within exhibition space will increase holding power of exhibit.

• 수산해양기술연구
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• 제40권3호
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• pp.225-231
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• 2004

The power and scale of 950 hPa typhoon "Maemi" which struck the shore of Gosung in Kyungnam Province was same as that of 951 hPa typhoon "Saraho" in 1959. For the purpose of getting the safety of training ship "KAYA", we anchored at Jinhae Bay with riding at two anchors paid out 8 shackles of cable respectively. By the way when wind force being over 30m/s, we could not keep the safety of the ship "KAYA" by means of the holding power of an anchor only. Just by using the main engine moderately, we were able to maintain the security of the ship. The holding the main engine moderately, we were able to maintain the security of the ship. The holding power of an anchor according to the way of anchoring, the quality of sea bottom, the direction and speed of wind and current, and the length of an anchor cable were analyzed. The obtained results are summarized as follows : 1. When riding at two anchors rather than lying at single anchor we could get a good holding power. 2. There was a big difference in holding power according to the quality of the bottom. 3. It would be best anchoring in a soft mud area than in any other place as possible. 4. It would also be desirable to set anchor shackles much more than equipment number prescribed in regulation in order to get safety of a ship providing against typhoon.