• Computers and Concrete
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• v.25 no.5
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• pp.461-470
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• 2020

This paper presents a numerical study on structural behavior of hammer head pier cap beams, extended on verges and reinforced with carbon fiber reinforced polymer (CFRP) plates. A 3-D finite element (FE) model along with a simplified analytical model are presented. Concrete damage plasticity (CDP) was adapted in the FE model and an analytical approach predicting the CFRP anchor strength was adapted in both FE and analytical model. Total five quarter-scaled pier cap beams with various CFRP reinforcing schemes were experimentally tested and analyzed with numerical approaches. Comparison between experimental results, FE results, analytical results and current ACI guideline predictions was presented. The FE results showed good agreement with experimental results in terms of failure mode, ultimate capacity, load-displacement response and strain distribution. In addition, the proposed strut-and-tie based analytical model provides the most accurate prediction of ultimate strength of extended cap beams among the three numerical approaches.

• Journal of the Korean Society of Hazard Mitigation
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• v.2 no.2 s.5
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• pp.95-104
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• 2002

This paper presents the pull-out failure mode on Headed Bars and prediction of tensile capacity, as governed by concrete cone failure. 17 different plate types, three different concrete strengths and three different welding types of specimens were simulated. Test variables are the reinforcing bar diameters connected to headed plate (e.g., 16mm, 19mm and 22mm), the head plate shapes (e.g., circular, square, rectangular), the dimensions of head plates (e.g., area and thickness), the types of welding scheme for connection of reinforcing bars and head plates (e.g., general welding and friction welding). Headed Bars were manufactured in different areas, which shape and thickness are based on ASTM 970-98. Calculation of Embedment length in concrete is based on CSA 23.3-94, and static tensile load was applied. Pullout capacities tested were compared to the values determined using current design methods such as ACI-349 and CCD method. If compare experiment results and existings, Headed bar expressed high strength and bigger breakdown radious than standard by wide plate area and anomaly reinforcing rod unlike anchor.

• Structural Engineering and Mechanics
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• v.47 no.3
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• pp.383-399
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• 2013

High-strength strands are widely used as a key structural element in cable-stayed bridges and prestressed concrete structures. Conventional strands for stay cable and tendons in prestressed concrete structures are ${\phi}$15.7mm coated seven-wire strands and ${\phi}15.2mm$ uncoated seven-wire strands, respectively, but the ultimate strengths of both strands are 1860MPa. The objective of this paper is to investigate the tensile behavior of a newly developed ${\phi}15.7mm$ 2,200 MPa coated strand and a ${\phi}15.2mm$ 2,400 MPa uncoated strand according to various types of mono anchorages and to propose appropriate anchorages for both strands. Finite element analyses were initially performed to find how the geometry of the anchor head affects the interaction among the anchor head, the wedge and the strand and to find how it affects the stress distributions in both parts. Tensile tests for the new strands were carried out with seven different types of mono anchorages. The test results were compared to each other and to the results obtained from the tensile tests with a grip condition. From the analysis and the test results, desirable mono anchorages for the new strands are suggested.

• Geotechnical Engineering
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• v.11 no.1
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• pp.63-78
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• 1995

Recently, in order to utilize more effectively underground space, deep excavations have been performed on building or subway construction in urban areas. In such excavations, anchors have been used to support the excavation retaining walls because the anchored excavation could provide wide working space for underground construction. The purpose of this paper is to establish empirical equations to be able to estimate the earth pressures acting on anchored excavation retention walls, based on the investigation of field measuring results, which were obtained from twenty seven building construction sites. The prestressed anchor force was measured by load cells which were attached to the anchor head, while the horizontal displacement of excavation walls were measured by inclinometers which were installed right'behind the retention walls. The lateral earth pressures acting on the anchored retention walls, which were estimated from both the measured anchor forces and the horizontal displacement of the walls, showed a trapezoidal distribution. There was some difference between the measured earth pressures acting on the anchored retention walls and the empirical earth pressures given by several empirical equations. Thus, the lateral earth pressures acting on anchored retention walls would be estimated by these empirical equations with some modifications.

• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.2
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• pp.149-153
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• 2002

Purpose: To evaluate the efficacy of arthroscopic Bankart repair using suture anchors for treatment of traumatic anterior instability of shoulder joint .Materials and Methods: We performed arthroscopic Bankart repair using suture anchor in 54cases and evaluated the results with the functional grading system of Rowe and Zarins after patients were followed up for more than 12 months. Results: Combined pathologies identified under arthroscopy were Hill-Sachs lesion in 28 cases, SLAP lesion in 6 cases and chondromalacia of humeral head in 6 cases. The results were excellent or good in 50 cases(92.6$\%$), and redislocation was happened only two cases. Conclusion: We conclude that arthroscopic Bankart repair with suture anchors is one of the reliableand effective method for treatment of recurrent shoulder dislocation with Bankart lesion.

• Journal of the Korean Arthroscopy Society
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• v.10 no.1
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• pp.70-76
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• 2006

Purpose: This study presents 5 patients who had metallic anchor protrusion on glenoid after Bankart repair in anterior shoulder instability and reviewed the cause, clinical feature and arthroscopic removal technique. Method and Materials: 5 male with average age of 22 years (range 19 to 25 years) were included. 4 patients had arthroscopic Bankart repair and 1 patient had open repair for anterior shoulder instability. They had protruded metallic suture anchors on glenoid and the protruded suture anchors were removed arthroscopically using larger suture anchor empty inserter. Results: 4 patients had painful clicking sound with motion of abduction and external rotation and 1 patient showed shoulder instability. The ROM showed normal except mild degrees loss of external rotation. The position of protruded metallic anchor was 2, 3 and 5 O'clock in three patients and 4 O'clock in 2 patients. In 2 patients, the metallic suture anchor was malpositioned about 5mm off on the medial side from the anterior glenoid edge. All had Outerbrige classification Grade II-III chondral damage on humeral head and 1 patient showed glenoid cartilage destruction. None had shoulder instability after 2 years of follow-up. Constant score was 65 preoperatively and 89 postoperatively. ASES score was 67 preoperatively and 88 postoperatively. Conclusion: Symptoms of protruded suture anchor are not combined with instability. Most of symptoms were revealed from the rehabilitation period and confused with postoperative pain. Prompt diagnosis and early arthroscopic removal or impaction of protruded metallic suture anchor is recommended because of serious glenohumeral cartilage destruction. This is easy and simple and reproducible method to remove protruded metallic suture anchor arthroscopically.

• Journal of Broadcast Engineering
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• v.25 no.7
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• pp.1073-1080
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• 2020

360-degree video streaming technologies have been widely developed to provide immersive virtual reality (VR) experiences. However, high computational power and bandwidth are required to transmit and render high-quality 360-degree video through a head-mounted display (HMD). One way to overcome this problem is by transmitting high-quality viewport areas. This paper therefore proposes a motion-constrained tile set (MCTS)-based tile extractor for versatile video coding (VVC). The proposed extractor extracts high-quality viewport tiles, which are simulcasted with low-quality whole video to respond to unexpected movements by the user. The experimental results demonstrate a savings of 24.81% in the bjøntegaard delta rate (BD-rate) saving for the luma peak signal-to-noise ratio (PSNR) compared to the rate obtained using a VVC anchor without tiled streaming.

• The korean journal of orthodontics
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• v.41 no.2
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• pp.112-120
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• 2011

Objective: Microscrew implants (MSls) offer many advantages, but some complications are known to occur during their insertion. One of the most commonly reported complications is root injury. Our aim was to identify factors associated with root injury and to evaluate their qualitative and quantitative values. Methods: Thirty-five orthodontists placed MSls (AbsoAnchor$AbsoAnchor^{(R)}$, Dentos Co. Ltd, Daegu, Korea) in the upper jaw of typodonts, labially between the second premolar and the first molar, in low and high vertical positions. Root contacts were counted, and distances between MSI apices and roots were measured. Fear level of the orthodontists was surveyed before and after the experiment. Wilcoxon's test, chi-square test, and Mann-Whitney test were used for statistical analysis. Results: Overall root contact rate of MSI insertion was 23.57%. The root contact rate was significantly higher in MSls inserted at $90^{\circ}$ (45.71%) than at $30^{\circ}$ (1.43%). The distance between the dental root and MSI also increased significantly in MSls inserted at $30^{\circ}$. Mean fear level before MSI insertion (4.6) significantly decreased after insertion (3.2); the causative factors were risk of injury to dental root and maxillary sinus or mandibular canal. Conclusions: Root injury is relatively rare, and oblique angulation reduces the risk of root and MSI contact.

• Journal of Veterinary Clinics
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• v.30 no.1
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• pp.45-48
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• 2013

A 12-year-old male poodle weighing 2.0 kg presented for evaluation of right thoracic limb lameness. The owner reported that the dog showed recurrent bilateral shoulder joint luxation after a car accident for a year. Recently, the left shoulder joint appeared well maintained, but right shoulder joint luxation was exacerbated. On physical examination, the dog showed non-weight bearing lameness on the right thoracic limb. Craniocaudal radiographic views revealed medial displacement of the right humerus. Mediolateral radiographic views revealed overlap of the glenoid cavity and humeral head. Muscle atrophy of the right thoracic limb, reduced biceps brachii muscle tendon tone, a tear of the medial glenohumeral ligament, and a rupture of the subscapularis tendon were identified intraoperatively. Transposition of the biceps muscle tendon was performed. However, at 7 days, there was evidence of right shoulder reluxation on radiographs. The second surgery was performed with two $2mm{\times}6mm$ cortical bone anchors and a $4mm{\times}6mm$ cancellous bone anchor placed in the cortical bone of the distal scapula and the cancellous bone of the proximal humerus respectively. Two scapular bone anchors were then connected with a humeral bone anchor using heavy nylon suture to minimize shoulder abduction range of motion. On radiographs right after surgery and 6 weeks after surgery, the affected limb revealed no evidence of medial shoulder luxation. At 6 months, no evidence of lameness was noted on the right thoracic limb.

• Journal of the Korean GEO-environmental Society
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• v.25 no.4
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• pp.29-35
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• 2024

This is an analytical study to confirm the passive resistance effect before post-tensioning of steel bar anchors. When using a steel bar as a permanent anchor, if displacement occurs within the slope even before the head load is applied, the displacement is suppressed by the passive resistance caused by the interaction between the steel bar, grout, and surrounding soil. Accordingly, the shape of the failure surface and changes in the safety factor were examined using limit equilibrium analysis and finite element analysis targeting sites where steel bar anchors were actually applied. It was found that the safety factor of the slope reinforced with steel bar anchors is 2.02 using finite element analysis, which is about 5.9% smaller than 2.14 using limit equilibrium analysis. Also, the location of the failure surface was found to be deeper compared to the unreinforced slope. Likewise, the factor of safety has a 153% and 163% increase using finite element method and limit equilibrium analysis, respectively. In addition, the maximum displacement occurs in the lower unreinforced section within the slope, and the displacement is found to be reduced by 42 to 83% at the location where the steel bar anchors are installed.