• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.267-270
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• 2005

Recently, the damaged concrete structures are often strengthened or repaired using the polymer concrete or the polymer cement mortar. In the repaired concrete structures at early ages, internal stresses could be developed due to the differential drying shrinkage of the repair material. Due to the difference of the thermal coefficients of the repair material and existing concrete, additional stresses also could be developed as the structures are subjected to the ambient temperature changes. Theses environmentally-induced stresses can sometimes be large enough to cause damage to the structures, such as debonding of the interface between the two materials. In this study, a rational procedure was developed where anchors can be designed and installed to prevent damages in such structures by thermally-induced stresses. Finally, through the experimental and numerical study, the effects of the repair method using anchors with debonding was investigated and discussed the results.

• The Journal of Korea Robotics Society
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• v.6 no.1
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• pp.58-68
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• 2011

This paper proposes a technique of indoor localization for mobile robot by so called indoor GPS and EKF. Basically the concept of indoor GPS is similar outdoor GPS, and the indoor GPS gets distances between Anchors and Tag by a ranging method of CSS and then estimates the coordinate by distances and known Anchor positions. After we performed performance test of indoor GPS system in ideal and multipath environment, we configured that the indoor GPS has internal error factors and external error factors. This paper handled a multipath problem belonging to external error factors. At first various direct physical method are introduced to fix the multipath problems, and as expected we got errors corrected considerably. And then the method of selective anchors for indoor GPS is applied. With these two level improvement of indoor GPS performance, EKF(Extended Kalman Filter) is applied to mobile robot in indoor environment. The usefulness of the proposed methods are shown by a series of experiments in a environment giving contaminated data by multipath.

• Journal of Korean Society of Steel Construction
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• v.25 no.4
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• pp.347-357
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• 2013

Recently, In recognition of outstanding structural performance the use of Concrete Filled steel Tube(CFT) columns has been increased. Research is ongoing that effective use of cross-sectional because steel strength development and rising prices. In this Lab, suggests new shape by Thin steel plates bent to be L-channel welded to form square steel tube to maximize efficiency of the cross section. In addition, since the rib placed at the center of the tube width acts as an anchor; higher load capacity of buckling is acceptable. we have developed New shape welded built-up square tube for broader usability which were bent to be L-shaped and thin Plate each unit member were welded. In order to apply the new shape built-up square columns, we predicted structure behavior, stress distribution with parameter Width thickness ratio. The experimental results presented in standards and even exceed the b/t of the rib anchors installed in the role due to exert enough strength and deformation to improve performance was favorable.

• Journal of the Korea Concrete Institute
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• v.17 no.6 s.90
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• pp.885-892
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• 2005

Recently, the damaged concrete structures are often strengthened or repaired using the polymer concrete or the polymer cement mortar. In the repaired concrete structures at early ages, internal stresses could be developed due to the differential drying shrinkage of the repair material. Due to the difference of the thermal coefficients of the repair material and existing concrete, additional stresses also could be developed as the structures are subjected to the ambient temperature changes. Theses environmentally-induced stresses can sometimes be large enough to cause damage to the structures, such as debonding of the interface between the two materials. In this study, a rational procedure was developed where anchors can be designed and installed to prevent damages in such structures by thermally-induced stresses. Finally, through the experimental study and numerical study, the effects of the repair method using anchors with debonding was investigated and discussed the results.

• Steel and Composite Structures
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• v.18 no.5
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• pp.1305-1330
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• 2015

The successful application of the component-based approach - widely used to model structural joints - requires knowledge of the mechanical properties of the constitutive joint components, including an appropriate assembly procedure to derive the joint properties. This paper presents a component-method model for a structural joint component that is located in the tension zone of blind-bolted connections to concrete-filled tubular steel profiles. The model relates to the response of blind-bolts with headed anchors under monotonic loading, and the blind-bolt is termed the "Extended Hollo-bolt". Experimental data is used to develop the model, with the data being collected in a manner such that constitutive models were characterised for the principal elements which contribute to the global deformability of the connector. The model, based on a system of spring elements, incorporates pre-load and deformation from various parts of the blind-bolt: (i) the internal bolt elongation; (ii) the connector's expanding sleeves element; and (iii) the connector's mechanical anchorage element. The characteristics of these elements are determined on the basis of piecewise functions, accounting for basic geometrical and mechanical properties such as the strength of the concrete applied to the tube, the connection clamping length, and the size and class of the blind-bolt's internal bolt. An assembly process is then detailed to establish the model for the elastic and inelastic behaviour of the component. Comparisons of model predictions with experimental data show that the proposed model can predict with sufficient accuracy the response of the component. The model furthers the development of a full and detailed design method for an original connection technology.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.14.1-14.11
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• 2020

Background: The purpose of this study is to introduce our modified disc plication technique using MITEK mini anchors and to evaluate the clinical outcome for patients with internal derangement (ID) of the temporomandibular joint (TMJ). Patients and methods: We evaluated 65 joints in 46 patients, comprised 32 women and 14 men, who first visited the Asan Medical Center from December 2012 to December 2016. The age of the patients ranged from 14 to 79 years, with a mean age of 36.6 years. The patients presented with joint problems including pain, joint noise, and mouth opening limitation (MOL). Patients who met our inclusion criteria underwent unilateral or bilateral disc repositioning surgery with our minimally invasive disc plication technique using MITEK mini anchors and No. 2-0 Ethibond^® braided polyester sutures. The variables taken into account in this study were the range of maximum mouth opening (MMO), painful symptoms (evaluated with the visual analog scale, VAS), and the type of noise (click, popping, crepitus) in the TMJ. Results: Preoperative examination revealed painful symptoms in 50.7% (n = 35) of the operated joints (n = 69) and the presence of clicks in 56.5% (n = 39). Postoperative examination revealed that 4.3% (n = 3) of the operated joints had painful symptoms with lower intensity than that in the preoperative condition. Additionally, 17.4% (n = 12) had residual noise in the TMJ, among which two were clicking and the other 10 had mild crepitus. The intensity of the postoperative residual noise was significantly decreased in all cases compared to that in the preoperative condition. Among patients with MOL below 38 mm (n = 18), the mean MMO was 31.4 mm preoperatively and 44.2 mm at 6 months postoperatively, with a mean increase of 13.8 mm. A barely visible scar at the operation site was noted during the postoperative observation period, with no significant complications such as facial palsy or permanent occlusal disharmony. Conclusion: Subjective symptoms in all patients improved following the surgery. TMJ disc plication using MITEK mini anchors with our minimally invasive approach may be a feasible and effective surgical option for treating TMJ ID patients who are not responsive to conservative treatment.

• Clinics in Shoulder and Elbow
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• v.9 no.1
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• pp.105-110
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• 2006

Purpose: This study reports the clinical results of the arthroscopic Bankart repair in traumatic anterior instability of the shoulder with bio-knotless anchor. Materials and Methods: 21 cases of 21 patients (20 male and 1 female) were included in this study. The average age was 24.8 years old and the period from the first injury to operation was average 37.2 months. All cases had Bankart lesion and 12 cases had Hill-Sachs' lesion. The SLAP lesion was associated in 6 cases. Preoperative Rowe score was average 29.1. Arthroscopic Bankart repair with bio-knotless anchor were performed in all cases; 3 anchors at 3, 4, 5 O'clock position of the glenoid were used in 11 cases and 2 anchors at 4, 5 O'clock position were used in 10 cases. All the associated SLAP lesions were repaired arthroscopically with bio-knotless anchor. Thermal capsular shrinkage at the anterior and inferior shoulder capsule after the Bankart repair was performed in 3 cases. The average follow up period was 20.2 months. Results: The Rowe score improved to 92.8, excellent in 17 cases and good in 4 cases, at last follow up period and 20 cases had full range of motion of the shoulder. 1 case had mild limited range of motion of the shoulder (150 degrees in flexion, 60 degrees in external rotation and T12 level in internal rotation) without any problem in normal activity. The arthroscopic revision surgery of the shoulder was performed in 1 case because of multiple traumatic injuries of the shoulder with pain postoperatively. Conclusion: Arthroscopic Bankart repair with bio-knotless anchor in traumatic anterior shoulder instability is one of the good methods because of the good clinical results.

• Journal of the Korean Arthroscopy Society
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• v.11 no.1
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• pp.32-38
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• 2007

Purpose: This study reports the clinical results of the arthroscopic repair of type V SLAP lesion with bio-knotless anchor. Materials and Methods: 10 cases of 10 patients (10 male) were included in this study. The average age was 32.7 years old and the period from the first injury to operation was average 47.2 months. Preoperative Rowe score was average 37.5. Arthroscopic SLAP repair with 1 or 2 bio-knotless anchors were performed and arthroscopic Bankart repair with bio-knotless anchors were performed in all cases; 3 anchors were used in 7 cases and 2 anchors in 3 cases. The average follow up period was 15.7 months. Results: The Rowe score improved to 93 at last follow up period and 8 cases had full range of motion of the shoulder. 2 case had mild limited range of motion of the shoulder (one case; 170 degrees in flexion, 60 degrees in external rotation and T12 level in internal rotation, the other case; 160 degrees in flexion, 45 degrees in external rotation and T12 level in internal rotation.) without any problem in normal activity. Conclusion: Arthroscopic repair with bio-knotless anchor in type V SLAP lesion is one of the good methods because of the good clinical results.

• Clinics in Shoulder and Elbow
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• v.24 no.2
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• pp.110-113
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• 2021

We present an unusual case of bone metastases from renal cell carcinoma around orthopedic implants in a 78-year-old female with osteolytic, expansile, highly vascularized, malignant infiltration around suture anchors in the proximal humerus. The patient had undergone arthroscopic rotator cuff repair using suture anchor implants 6 years previously. After diagnosis of bone metastasis, she was successfully treated with metastasectomy and internal fixation using a plate and screws, with cement augmentation. This report is the first to document metastases around a suture anchor in a bone and suggests the vulnerability of suture anchor implants to tumor metastasis.

• Journal of Korean Orthopaedic Sports Medicine
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• v.6 no.1
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• pp.57-65
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• 2007

Purpose: The purpose of this study was to evaluate the clinical result of arthroscopic treatments by using suture anchors or suture anchors combined with cannulated screw in the greater tuberosity fracture of the proximal humerus fracture. Materials and Methods: From March 2004 to March 2006 we have used suture anchor or suture anchors combined with cannulated screw for 6 cases of the greater tuberosity fracture which include displaced fractures, comminuted fractures and minimally displaced fractures with comcomittent lesions such as rotator cuff tears, stiffness and labral lesion. In this retrospective study, we analyzed the clinical outcomes by using the range of motion, University of California at Los Angeles shoulder rating scale (UCLA) and the ASES shoulder index score (ASES) in the average 6 months follow up. Results: At the last follow up, average range of motion was improved to 154.3 degree, 145.8 degree, 32.6 degree and L1 vertebrae in each forward flexion, abduction, external rotation and internal rotation. Clinically the UCLA rating scales improved to 31.5 and the ASES shoulder index score (ASES) improved to 93.6 in the last follow up. Conclusion: Arthroscopic treatments by using suture anchor or suture anchors combined with cannulated screw in the greater tuberosity fracture of the proximal humerus fracture is an alternative treatment of the greater tuberosity fracture of the proximal humerus fracture.