• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1286-1293
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• 2010

The ground anchor used in domestic area, which resists by adhesion between anchor body and the ground to the external force, seems not to be adequate for soft ground and urban area where the boundary between structures is close because the ground is disturbed and lost its strength during boring. In order to overcome such a shortcoming an expanded anchor system has been developed. The ground expansion is accomplished by means of Pulse Discharge Technology. In this technology, a high voltage of electricity is stored and discharged in milliseconds which induces high pressure acting on the ground. By making a couple of bulbs, a passive resistance as well as shaft resistance are mobilized, and therefore a higher pullout resistance comparing existing ground anchors is developed.In this study, a couple of full scale tests were conducted in order to figure out how much the resistance of an expanded anchor increases comparing to the straight. As a result, it was found that a remarkable increase in ultimate pullout capacity is observed for the soft ground and as the number of bulb increases. In addtion, as a result of applying to a cut slope reinforcement, it appeared that the length of fixed zone of anchor can be reduced effectively.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2002년도 가을 학술발표논문집 Vol.29 No.2 (2)
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• pp.157-159
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• 2002

웹 Annotation은 개인 노트의 수단이며, 동료들 사이에서 의견 교환과 협업할 수 있도록 도와준다[l]. 또한, Annotation들은 데이터베이스, 문서, 그리고 분산된 환경에서 중요한 일이나 사건을 기록하는데 바람직하다[2]. 이런 Annotation들은 통신수단의 발달과 함께 증가한 인터넷 사용자들의 활발한 의견교환을 통해 빠르게 증가하고 있다. 때문에 사용자들은 많은 Annotation들 중 적절한 Annotation을 선택하기가 쉽지 않다. 현재, 웹 상에서의 Annotation에 관련된 연구들이 활발히 진행 중에 있다. 그러나 한 문서 또는 한 Anchor에 존재하는 많은 Annotation들을 효과적으로 제공하는 방법에 관한 연구는 미비한 실정이다. 기존의 대부분의 Annotation System들은 다수의 Annotation들을 관련성이나, 사용자 특성을 고려하지 않고, 입력된 무의미한 순서로 제공하며 생성된 anchor와 Annotation들을 모두 보여준다. 이로 인해, 한 문서에 너무 많은 Annotation이 생성되어 문서의 레이아웃을 손상시킬 수 있으며[3], anchor와 문서의 이해 시간을 가중시킨다[4]. 따라서 본 논문에서는 웹 문서에 생성된 다수의 Anchor들과 Annotation들을 좀 더 효율적으로 제공하기 위해 협업 환경에서 효과적인 Social Filtering[5]을 적용하여 적절한 Anchor와 Annotation만을 제공하는 사용자 관심사에 의한 Annotation 처리 기법을 제안한다. 더불어 한 Anchor에 생성된 Annotation들에 순위를 부여하여 보다 적절한 Annotation을 먼저 접근할 수 있는 Anchor에 대한 적절한 Annotation내에서의 순위부여 기법을 제안한다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.1107-1112
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• 2009

Ground anchor should not be used in soft clay, because anchor resistance can not be guaranteed. However, there is a way to increase the capacity of anchors. The pulse powered anchor is an underreamed anchor by using high voltage electrokinetic pulse energy. In this study, a series of field test were carried out in order to find expansion rate related in number of pulse charge. and Anchor pull-out tests were performed at the Geotechnical Experimentation Site at Sungkyunkwan University in Suwon, Korea. Data were analyzed in order to define a relation between expansion rate and ultimate pullout load.

• KCI Concrete Journal
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• 제11권3호
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• pp.201-210
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• 1999

An experimental study was carried out to determine pullout behavior of a new type of anchor bolt that used deformed reinforcement and a commercial adhesive. Concrete slabs and columns with about 20-MPa compressive strength were used for 136 pullout tests performed. Test variables included anchor diameter (10 mm ~ 32 mm). embedment depth (10$\Phi$ or 15$\Phi$), edge effect. and Presence of transverse reinforcement in existing concrete. In Tyre-S test. where the edge or reinforcing steel effect was not included, the anchor Pullout strengths increased with increasing anchor diameters. Anchors with 15$\Phi$ embedment depth had higher Pullout strengths than those with 100 embedment depth The largest average Pullout load of 208 kN was determined for anchors made with D25 reinforcement and with 15$\Phi$ embedment depth. In Type-E tests, where the anchors were installed close to the edge of existing concrete, there were reductions in pullout strengths when compared to those determined in Type-S tests. In Type-ER tests, influence of the reinforcement in existing concrete on the anchor pullout strengths was examined using reinforced concrete and plain concrete columns Test results indicated that existing transverse reinforcement (column ties) did not help increase the pullout strength. The overall pullout test results revealed that the new anchor bolt can develop large pullout strengths while the anchors can be made of materials that are readily available in the market.

• Geomechanics and Engineering
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• 제13권5호
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• pp.825-844
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• 2017

This study aimed to find out the pullout capacity of inclined strip anchor plate embedded in anisotropic and nonhomogeneous fully saturated cohesive soil in undrained condition. The ultimate pullout load has been found out by using numerical lower bound finite element analysis with linear programming. The undrained pullout capacity of anchor plate of width B is determined for different embedment ratios (H/B) varying from 3 to 7 and various inclination of anchor plates ranging from $0^{\circ}$ to $90^{\circ}$ with an interval of $15^{\circ}$. In case of anisotropic fully saturated clay the variation of cohesion with direction has been considered by varying the ratio of the cohesion along vertical direction ($c_v$) to the cohesion along horizontal direction ($c_h$). In case of nonhomogeneous clay the cohesion of the undrained clay has been considered to be increased with depth below ground surface keeping $c_v/c_h=1$. The results are presented in terms of pullout capacity factor ($F_{c0}=p_u/c_H$) where $p_u$ is the ultimate pullout stress along the anchor plate at failure and $c_H$ is the cohesion in horizontal direction at the level of the middle point of the anchor plate. It is observed that the pullout capacity factor increases with an increase in anisotropic cohesion ratio ($c_v/c_h$) whereas the pullout capacity factor decreases with an increase in undrained cohesion of the soil with depth.

• Geomechanics and Engineering
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• 제9권6호
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• pp.689-707
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• 2015

Progressive increase in population causing land scarcity, which is forcing construction industry to build multistory buildings having underground basements. Normally, basements are constructed for parking facility. This research work evaluates important factors which have caused the collapse of pile-anchor system at under construction five star hotel. 21 m deep excavation is carried out, to have five basements, after installation of 600 mm diameter cast in-situ contiguous concrete piles at plot periphery. To retain piles and backfill, soil anchors are installed as pit excavation is proceeded. Before collapse, anchors are designed by federal highway administration procedure and four anchor rows are installed with three strands per anchor in first row and four in remaining. However, after collapse, system is modeled and analyzed in plaxis using mohr-coulomb method. It is investigated that in-appropriate evaluation of soil properties, additional surcharge loads, lesser number of strands per anchor, shorter grouted body length and shorter pile embedment depth caused large deformations to occur which governed the collapse of east side pile wall. To resume work, old anchors are assumed to be standing at one factor of safety and then system is analyzed using finite element approach. Finally, it is concluded to use four strands per anchor in first new row and five strands in remaining three with increase in grouted and un-grouted body lengths.

• 한국컴퓨터정보학회논문지
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• 제24권5호
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• pp.1-9
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• 2019

In this paper, we propose the algorithms which determine 1) the efficient anchor-node visiting route of mobile sink in terms of energy supply and 2) the efficient energy amount to be charged to each anchor node, by using the information of each anchor node and the mobile sink. Wireless sensor networks (WSNs) using mobile sinks can be deployed in more challenging environments such as those that are isolated or dangerous, and can also achieve a balanced energy consumption among sensors which leads to prolong the network lifetime. Most mobile sinks visit only some anchor nodes which store the data collected by the nearby sensor nodes because of their limited energy. The problem of these schemes is that the lifetime of the anchor nodes can be shorten due to the increased energy consumption, which rapidly reduces the overall lifetime of WSN. This study utilizes a mobile sink capable of wireless power transmission to solve this problem, so a mobile sink can gather data from anchor nodes while charging energy to them. Through the performance verification, it is confirmed that the number of blackout nodes and the amount of collected data are greatly improved regardless of the size of the network.

• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1382-1393
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• 2022

This paper investigates the seismic behavior of an electrical cabinet considering the influence of equipment-anchor-interaction (EAI) that is generally not taken into consideration in a decoupled analysis. The hysteresis behavior of an anchor bolt in concrete was thereby considered to highlight this interaction effect. To this end, the experimental behavior of an anchor bolt under reversed cyclic loading was taken from the recently developed literature, and a numerical model for the anchor hysteresis was developed using the component approach. The hysteresis properties were then used to calibrate the multi-linear link element that is implemented as a boundary condition for the cabinet incorporating the EAI. To highlight this EAI further, the nonlinear time history analysis was performed for a cabinet considering the hysteresis behavior comparative to a fixed boundary condition. Additionally, the influence on the seismic fragility was evaluated for the operational and structural condition of the cabinet. The numerical analysis considering the anchor hysteresis manifests that the in-cabinet response spectra (ICRS) are significantly amplified with the corresponding reduction in the seismic capacity of 25% and 15% for an operational and structural safety condition under the selected protocols. Considering the fixed boundary condition over a realistic hysteresis behavior of the anchor bolt is more likely to overestimate the seismic capacity of the cabinet in a seismic qualification procedure.

• 수산해양기술연구
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• 제59권2호
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• pp.135-144
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• 2023

In order to provide basic data to increase the efficiency and stability of seamanship at anchoring, the characteristics of the hull motion including dragging anchor due to external forces were observed at Mokpo and Jinhae anchorage for the avoidance of the typhoon. As a result, it is necessary to check the embedding motion and holding power of the anchor according to at initial position to decrease dragging anchor. Dragging anchor at anchorage seems to have been easily caused according to discrepancy between embedded anchor flukes and the towing direction due to the change in wind direction, rather than the wind speed. This discrepancy, thus, should be considered when anchoring. This test vessel with a small radius of curvature of the stem is relatively vulnerable to the influence of wind direction and wind speed, so it is easy to cause a decrease in the holding power due to an increase in the rate of turn. When the current speed is greater than or equal to 1 knot, the range of the rate of turn is reduced resulting in a relatively increased holding power. In addition, during the swing, the tension of the chain was high according to the angular velocity change of heading at three-quarters of the swing length rather than the left and right ends.

• 대한정형외과스포츠의학회지
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• 제10권2호
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• pp.69-77
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• 2011

목적: 만성 발목관절 외측 불안정성 환자에 대한 변형 Brostrom 술식에서 단일 봉합나사와 이중 봉합나사를 이용한 기법간의 임상 결과를 후향적으로 비교하고자 하였다. 대상 및 방법: 본원에서 봉합나사를 이용한 변형 Brostrom 술식을 시행받은 환자들 중 최소 1년 이상 추시가 가능하였던 37례를 대상으로 하였다. 모든 수술은 동일한 술자에 의해 이루어졌으며 단일 봉합나사를 이용한 경우가 17예, 이중 봉합나사를 이용한 경우가 20예 였다. 임상적 결과의 평가는 Karlsson 점수 및 Sefton의 평가법을 이용하였고, 발목관절의 기계적인 안정성에 대한 방사선학적 평가로 Telos 기기를 이용한 전방 전위 및 내반 스트레스 검사가 이용되었다. 결과: Karlsson 점수는 단일 봉합나사군이 술 전 평균 45.2점에서 술 후 89.4점으로, 이중 봉합나사군이 술 전 평균 46.4점에서 90.5점으로 각각 호전되었다. Sefton 평가법상 단일 봉합나사군은 우수가 7예, 양호가 8예, 보통이 2예 였고, 이중 봉합나사군은 우수 8예, 양호 10예, 보통 2예로 나타나 각각 15례(88.2%), 18례(90%)에서 만족스러운 결과를 보였다. 스트레스 방사선검사 상 거골 경사각과 거골 전방전위는 단일 봉합나사군이 술 전 평균 13.6도, 8.6 mm에서 술 후 최종 추시시 5.4도, 4.1 mm로, 이중 봉합나사군이 술 전 평균 14.1도, 8.4 mm에서 술 후 3.9도, 4 mm로 각각 호전되었으며 두 기법간에 술 후 거골 경사각의 유의한 차이를 보였다(p<0.05). 결론: 만성 발목관절 외측 불안정성에 대한 변형 Brostrom 술식에서 단일 봉합나사와 이중 봉합나사를 이용한 기법간에 술 후 임상 결과의 유의한 차이는 없었으나, 발목관절의 기계적인 안정성은 이중 봉합나사군에서 더 우수하였다. 단일 봉합나사와 이중 봉합나사를 이용한 변형 Brostrom 술식 모두 효과적인 치료 방법이라고 생각되며, 향후 운동 선수들을 대상으로 한 치료결과 및 생역학적 분석이 필요할 것으로 생각한다.