• International Journal of Highway Engineering
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• v.18 no.4
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• pp.37-45
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• 2016

PURPOSES : The objective of this study was to develop an impact resonance (IR) test procedure for thin disk-shaped specimens in order to determine the ${\mid}E^*{\mid}$ and phase angle values of various asphalt mixtures. METHODS : An IR test procedure was developed for evaluating thin disk-shaped specimens, in order to determine the dynamic modulus (${\mid}E^*{\mid}$) of various asphalt mixtures. The IR test method that was developed to determine the elastic modulus values of Portland cement concrete was evaluated, which method uses axisymmetric flexural vibration proposed by Leming et al. (1996). The IR tests were performed on three different mixtures of New York with varying nominal maximum aggregate sizes (NY9.5, NY19, and NY25) at six different temperatures ($10-60^{\circ}C$). The ${\mid}E^*{\mid}$ values obtained from the IR tests were compared with those determined by the commonly used AASHTO T342-11 test. RESULTS AND CONCLUSIONS : The IR test method was employed to determine the ${\mid}E^*{\mid}$ values of thin-disk-shaped specimens of various asphalt mixtures. It was found that the IR test method when used with thin disk-like specimens is a simple, practical, and cheap tool for determining the ${\mid}E^*{\mid}$ values of field cores. Further, it was found the ${\mid}E^*{\mid}$ values obtained from the IR tests using thin disk-like specimens were almost similar to those obtained using the AASHTO T342-11 test.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.531-535
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• 2006

Purpose: To report our experience of retro-angular flap for reconstruction of the midface defect. The midface, including nose, lower eyelid, and intercanthal area, is the very prominent area of face. Also midface is more vulnerable to trauma and skin cancer and defect of mid face of highly perceptible. Reconstruction of mid face is difficult because of complexity of anatomy and functions. Following factors should be considered in reconstructive prcedure of midface. First, multiple procedure may need for complete the reconstruction of mid face defect. Second, secondary reconstructive surgeries such as flap rotation or skin graft may need for donor site morbidity. Third, the color, texture and thickness of the skin used are not always complacency. Methods: 8 cases of the midface defects (3 cases of lower eyelid, 1 case of intercanthal area, and 4 cases of nose) from skin cancer were reconstructed with retroangular flap from March 2004 to August 2005. Results: Satisfactory result were obtained in color, texture and donor site scar. There was no major complication such as wound disruption, hematoma, and atrophy of flap. But partial necrosis of flap and bulkiness were observed one case in each. Retroangular flap is simple procedure that can be preceded in one stage under local anesthesia closing primary wound closure. It will leave less visible donor scar, acceptable color, texture and thickness of the skin. Conclusions: The retro-angular flap could be suggested as a safe and effective method for midface reconstruction.

• Archives of Plastic Surgery
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• v.33 no.5
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• pp.570-576
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• 2006

Purpose: Skin-sparing mastectomy(SSM) with immediate breast reconstruction is becoming a proved option for early-stage breast cancer patients. Recently, skin-sparing mastectomy with preserving the nipple-areolar complex is becoming popular procedure. Methods: During a 13-month period, from April 2004 to January 2005, 101 cases of immediate breast reconstructions with pedicled TRAM flap were performed after 40 cases of nipple-areolar sparing mastectomies, 57 cases of skin-sparing mastectomies and 4 cases of modified radical mastectomies. Results: During the 11 months follow up period, necrosis of mastectomy skin flap occurred in 17.5%(n=10) after skin-sparing mastectomy and necrosis of mastectomy skin flap and nipple-areolar necrosis occurred in 30%(n=12) after nipple-areolar sparing mastectomy. These complications were healed after simple dressing without any surgical procedure. Conclusion: Nipple-areolar sparing mastectomy and immediate breast reconstruction with TRAM flap is good option for early breast cancer patients and some modifications are needed to reduce skin necrosis.

• Journal of Chest Surgery
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• v.17 no.3
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• pp.456-464
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• 1984

Since the advent of potent chemotherapy, the incidence and severity of bronchiectasis have been on the decrease. Up to date, however, the medical treatment of bronchiectasis has not given us much satisfaction. Our purpose here is to show our experiences with pulmonary resections of bronchiectasis to clarify its surgical results and define its surgical indications. Sixty-five patients with bronchiectasis, treated surgically from January 1973 to December, 1982 at the Department of Thoracic and Cardiovascular Surgery, Kyungpook National University Hospital, were given clinical assessment. Of the 65 patients involved in the series, 49 were male and 16, female. The patients ranged from 8 to 51 in ages, with 59 cases [91%] between 10 and 39 years old. The prominent clinical features were as follows: cough [88%], sputum production [78%], recurrent upper respiratory infection [51%], and frequent hemoptysis [32%]. The past history of the patients included measles 29%, whooping cough 14%, pulmonary tuberculosis 12%, and pneumonia or bronchitis 12%. The cylindrical type of the bronchiectasis was found to be most common, accounting for 43% of the cases. The operations were performed on the left lung in 52 cases and the right lung in 13 cases. The most common operative procedure was the left lower lobectomy and lingular segmentectomy, which showed 34%. The second most frequent procedure was the simple left lower lobectomy which was 22%. Incomplete resections of the multisegmental bronchiectasis were carried out in 12 cases, of which 7 cases were satisfactory Four patients underwent bilateral pulmonary resections for the severe multisegmental bilateral bronchiectases, during the first and second operations. Improvement in pulmonary symptoms was generally obtained in all four cases. The follow-up ranged from 1 week to 7 tears, with an average of 18.8 months. The overall results revealed that 87% of these and excellent or good conditions, but 13% had persistent symptoms. There was one operative death, which is a 1.5% mortality.

• Journal of Chest Surgery
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• v.28 no.5
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• pp.499-503
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• 1995

Since the insertion of self expandable metalic stent[SEMS has became popular method for hollow organ stenosis, many attempts for further apply the stent to airway stenosis as an simple procedure has been made, but intrabronchial migration of stent or occurrence of inflammatory granuloma around stent develop occasionally and sometimes it worsen bronchial stenosis further more. This report describes 2 case of surgically treated bronchial restenosis in whom intrabronchial stent were applied for release of bronchial stenosis. Our surgical option was pneumonectomy and bronchoplasty with sleeve right middle and upper lobectomy respectively. During the operation we found the SEMSs were tightly impacted in restenotic bronchial lumen with overgrowth of granulation tissues. The bronchial obstructions occupied more than 90% of lumens in both cases, and needed much complicated procedure to be relieved. Therefore, even though the insertion of SEMS remains as a prcedure determined by the physician`s preference, it has to be considered prudently that the use of SEMS can cause severe restenosis and the surgeon has more difficulties in performing segmental resection of restenotic bronchus in patient with SEMS previously inserted. Throughout these experiences we can conclude that the insertion of SEMS must be performed only in very selected cases of bronchial stenosis.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.4
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• pp.172-177
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• 2008

In this paper, we design an authentication protocol based on Fuzzy Signature Vault Scheme using a light signature feature extraction method for user convenience and efficiency of electronic commerce. The signature is used broadly in electronic commerce because it is one of the simple and low-cost biometric items. However, signature has a problem that there are few low-cost and safe protocols. To solve this problem, we design a feature extraction method which is adequate for characters of signature and Fuzzy Vault Scheme. In addition, we design and analyze an efficient authentication protocol with some parameters used in this procedure. The followings are advantages when this protocol is applied to authentication procedure; 1) using convenient and low-cost signatures, 2) being possible to verify users with spending only about second for signature processing and authentication, 3) one time on transmission for sign-in and verification and 4) getting user authentication with secret value at the same time.

• Structural Engineering and Mechanics
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• v.56 no.4
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• pp.667-694
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• 2015

The suspended dome system is a new structural form that has become popular in the construction of long-span roof structures. Suspended dome is a kind of new pre-stressed space grid structure that has complex mechanical characteristics. In this paper, an optimum topology design algorithm is performed using the enhanced colliding bodies optimization (ECBO) method. The length of the strut, the cable initial strain, the cross-sectional area of the cables and the cross-sectional size of steel elements are adopted as design variables and the minimum volume of each dome is taken as the objective function. The topology optimization on lamella dome is performed by considering the type of the joint connections to determine the optimum number of rings, the optimum number of joints in each ring, the optimum height of crown and tubular sections of these domes. A simple procedure is provided to determine the configuration of the dome. This procedure includes calculating the joint coordinates and steel elements and cables constructions. The design constraints are implemented according to the provision of LRFD-AISC (Load and Resistance Factor Design-American Institute of Steel Constitution). This paper explores the efficiency of lamella dome with pin-joint and rigid-joint connections and compares them to investigate the performance of these domes under wind (according to the ASCE 7-05), dead and snow loading conditions. Then, a suspended dome with pin-joint single-layer reticulated shell and a suspended dome with rigid-joint single-layer reticulated shell are discussed. Optimization is performed via ECBO algorithm to demonstrate the effectiveness and robustness of the ECBO in creating optimal design for suspended domes.

• Structural Engineering and Mechanics
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• v.35 no.1
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• pp.99-117
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• 2010

Beam-column joints are the key structural elements, which dictate the behavior of structures subjected to earthquake loading. Though large experimental work has been conducted in the past, still various issues regarding the post-yield behavior, ductility and failure modes of the joints make it a highly important research topic. This paper presents experimental results obtained for eight beam-column joints of different sizes and configuration under cyclic loads along with the analytical evaluation of their response using a simple and effective analytical procedure based on nonlinear static pushover analysis. It is shown that even the simplified analysis can predict, to a good extent, the behavior of the joints by giving the important information on both strength and ductility of the joints and can even be used for prediction of failure modes. The results for four interior and four exterior joints are presented. One confined and one unconfined joint for each configuration were tested and analyzed. The experimental and analytical results are presented in the form of load-deflection. Analytical plots are compared with envelope of experimentally obtained hysteretic loops for the joints. The behavior of various joints under cyclic loads is carefully examined and presented. It is also shown that the procedure described can be effectively utilized to analytically gather the information on behavior of joints.

• Journal of Korean Neurosurgical Society
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• v.38 no.4
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• pp.259-264
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• 2005

Objective : The vertebroplasty is an excellent procedure in spine compression fracture, but there are some problems such as cement leakage and difficulties in bone biopsy. Recently, the osteoplasty system is developed to solve these problems, so we will report the usefulness of the osteoplasty system. Methods : From January 2003 to November 2003, there are 9patients with simple osteoporotic spine compression fracture, 2 compression fracture patients combined with suspicious spinal metastasis, 1patient with suspicious primary bone tumor, and 2patient with infection on spine. All patients were treated using the osteoplasty system. Results : All 11 compression fracture patients were relived the back pain after the osteoplasty and there is no complication. The bone biopsies in 3 suspicious cancer patients were also effectively performed using the osteoplasty system; negative result in 2patients and positive result in 1patient. The culture result of spontaneous discitis was no growth for 48hours. The spine tuberculosis was confirm using the osteoplasty system. Conclusion : The osteoplasty system has distinguished advantages in comparison with the vertebroplasty. That is, the risk of cement leakage is lower than vertebroplasty because of low pressure delivery system. And we can obtain the specimen effectively in bone biopsy because of large cannula. In conclusion, we emphasize that the osteoplasty system is a more useful procedure in spine compression fracture especially in the patient needed bone biopsy for diagnosis.

• Journal of Ocean Engineering and Technology
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• v.28 no.2
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• pp.126-132
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• 2014

In this study, a method for analyzing the collision and interaction between ice bergy bits and a Mark III type liquid natural gas (LNG) carrier was considered, and the structural safety of a ship's hull and cargo containment system (CCS) was evaluated. In the analysis, a constitutive model implementing the strain rate dependant mechanical property was used to consider the typical material characteristics of ice rationally. A relatively simple and easy ice structure interaction analysis procedure, compared with the accurate but complicated FSI analysis scheme, was suggested. When the ice bergy bits collided with ship's side hull under the four assumed scenarios, the structural behaviors of the ship structure and LNG CCS were simulated by applying the suggested ice collision analysis procedure using the commercial hydro-code LS-DYNA. In addition, the effects of the shapes and colliding speed of the ice bergy bits on the ice-structure interaction and safety of the CCS were examined in detail.