• Journal of the Korea Concrete Institute
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• v.25 no.4
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• pp.381-388
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• 2013

This study presents that effect of anchor plate on concrete breakout strength was evaluated. The addition of the anchor plate is to improve the concrete breakout capacity for a single anchor system in a thin-walled concrete panel (Insulated concrete sandwich wall panel). In this study, an elasticity-based simplified model was developed and used to predict effect on the anchor plate. Flexural stresses of the plate with respect to the concrete breakout strength obtained from CCD (Capacity Concrete Design) approach were compared with the test results. Through the test results, while the concrete breakout strength was improved due to increment of the width and thickness of the anchor plate, improvement of the strength was steadily declined. In addition, the It was observed that the analytical and experimental flexure of the anchor plate was comparatively in good agreement using the simplified elastic analysis model.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.265-270
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• 2002

In this paper, structural behaviors of anchor systems subjected to shear loads are analyzed by using fracture analysis and experiments. Two dimensional finite element analyses of concrete anchor systems to predict breakout failure of concrete through progressive fracture are carried out by utilizing the so-called embedded crack model. Three dimensional finite element analyses are also carried out to investigate the fracture behavior of anchor systems having different effective lengths, edge distances, spacings between anchors, and direction of loads. Results of analyses are compared with both experimental results and design values of ACI code on anchor, and then applicability of finite element method for predicting fracture behavior of concrete anchor systems is verified.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.11
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• pp.2992-3007
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• 2012

Recently there has been an increasing interest in exploring the radio irregularity research problem in Wireless Sensor Networks (WSNs). Measurements on real test-beds provide insights and fundamental information for a radio irregularity model. In our previous work "LMAT", we solved the path planning problem of the mobile anchor node without taking into account the radio irregularity model. This paper further studies how the localization performance is affected by radio irregularity. There is high probability that unknown nodes cannot receive sufficient location messages under the radio irregularity model. Therefore, we dynamically adjust the anchor node's radio range to guarantee that all the unknown nodes can receive sufficient localization information. In order to improve localization accuracy, we propose a new 2-hop localization scheme. Furthermore, we point out the relationship between degree of irregularity (DOI) and communication distance, and the impact of radio irregularity on message receiving probability. Finally, simulations show that, compared with 1-hop localization scheme, the 2-hop localization scheme with the radio irregularity model reduces the average localization error by about 20.51%.

• Journal of Korea Multimedia Society
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• v.25 no.4
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• pp.600-609
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• 2022

In supervised learning, labeling of all data is essential, and in particular, in the case of object detection, all objects belonging to the image and to be learned have to be labeled. Due to this problem, continual learning has recently attracted attention, which is a way to accumulate previous learned knowledge and minimize catastrophic forgetting. In this study, a continaul learning model is proposed that accumulates previously learned knowledge and enables learning about new objects. The proposed method is applied to CenterNet, which is a object detection model of anchor-free manner. In our study, the model is applied the knowledge distillation algorithm to be enabled continual learning. In particular, it is assumed that all output layers of the model have to be distilled in order to be most effective. Compared to LWF, the proposed method is increased by 23.3%p mAP in 19+1 scenarios, and also rised by 28.8%p in 15+5 scenarios.

• Geotechnical Engineering
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• v.10 no.4
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• pp.39-52
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• 1994

The group effect of inclined ground anchor should be considered in design, but it has been hardly studied due to the difficulties of experimental or theoretical study. In this study, the model tests for the inclined ground anchors are made, and the displacements and strain fields of ground around anchor surface are analysed. As the results of this study, the group effect of the inclined ground anchor in air dried sand ground does not show even though two anchor surfaces are very close(10.7cm, surface to surface). That is to say, ,in the case that the final failure surface by pullout of anchor shows on the anchor surface, the pullout resistances of single anchors are almost same as those of the group anchors in these model tests.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.12
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• pp.1543-1548
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• 2011

Structural analysis is performed to design anchor straps for a large-scale-liquefied-natural-gas (LNG) storage tank with corner protection and an inner tank by considering structural integrity. Anchor straps made of 9% nickel steel are attached to the inner tank, corner protection, and concrete raft to prevent the failure of the inner tank during both normal and emergency operating conditions. Two finite element (FE) models were analyzed in this study. One is a stand-alone model of the anchor strap, while the other is an extended model of the substructure of the anchor strap, inner tank, and corner protection. Three-dimensional shell elements are used to effectively assess the bending and axial behavior of structures. The Tresca stress values in each part of the two models are calculated for operation under five different load-condition cases: normal operation, leakage of the LNG, hydro test, and two earthquake conditions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.1
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• pp.50-59
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• 2007

In this paper, an anchor shot detection method, which is a basic technology for managing news videos for index and retrieval purposes is proposed. To do that, two most popular news program such as 'KBS 9 Hour News' and 'MBC 9 Hour News' are analyzed and 4-step rule based detection method is proposed First, in the preprocessing, video shot boundaries are detected and the 1st frame of each shot is extracted as a key frame. Then, the detected shot is declared as an anchor shot, if all the following 4 conditions are satisfied. 1) There is an anchor face in the key frame of a shot. 2) Spatial distribution of edges in the key frame is adequate. 3) Background color information of the key frame is similar to the color information of an anchor model. 4) Motion rate in the shot is low. In order to show the validity of the proposed method, three 'KBS 9 Hour News' and three 'MBC 9 Hour News', which have total running time of 108 in minute and are broadcasted at different days, are used for experiments. Average detection rates showed 0.97 in precision, 1.0 in recall, and 0.98 in F-measure.

• Geotechnical Engineering
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• v.6 no.1
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• pp.43-58
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• 1990

In order to get ultimate pullout resistance of ground anchor, the position of failure surface, normal stress and friction angle on the failure surface should be known. In this study, the position of failure surface is obtained by observing deformation of ground around anchor, and stresses on the anchor surface are analyzed by measuring normal and shear stresses on the anchor surface through model anchor test in plane strain. In addition, the relationship between lateral earth pressure and the position of failure surface is analyzed and the formula for calculating ultimate pullout resistance of anchor is proposed by using non-dimensional coefficient of ultimate pullout resistance.

• Geomechanics and Engineering
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• v.22 no.3
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• pp.265-275
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• 2020

As a flexible supporting structure, the anchoring frame structure is widely adopted to support multistage slopes in high earthquake-intensity area for its effectiveness and practicality. The previous study indicates that the anchor of anchoring frame structure is the most likely to be damaged during earthquakes. It is crucial to determine the pull-out capacity of anchor against seismic force for the seismic design of anchoring frame structure. In this study, an analytical model of a three-stage slope supported by anchoring frame structure is established, and the upper bound method of limit analysis is applied to deduce the seismic anchor force of anchoring frame structure. The pull-out capacity of anchor against seismic force of anchoring frame structure at each stage is obtained by computer programming. The proposed method is proved to be reasonable and effective compared with the existing published solution. Besides, the influence of main parameters on the pull-out capacity of anchor against seismic force is analyzed to provide some recommendations for the seismic design of anchoring frame structure.

• Journal of Ocean Engineering and Technology
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• v.28 no.1
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• pp.47-54
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• 2014

When an anchor penetrates and is installed under a seabed, a portion of the mooring line connected to the anchor is also embedded under the seabed. This embedded mooring line affects the capacity of the anchor in two ways. First, the frictional resistance that occurs between the mooring line and the seabed reduces the pulling force acting on the anchor. Second, the embedded part of the mooring line forms a reverse catenary shape due to the bearing resistance of the soil, so that an inclined pulling force is applied to the anchor. To evaluate the mooring line's effect on the capacity of an anchor in sand, centrifuge model tests were performed using two relative sand densities of 76% and 51% while changing the anchor depths. The test results showed that the load is reduced much more in deep and dense sand, and the inclination angle of the load is lower in shallow and loose sand.