• Steel and Composite Structures
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• v.16 no.6
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• pp.595-609
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• 2014

The paper is reporting some comparisons between experimental and numerical results in terms of failure mode, failure time and ballistic properties of mild steel sheet. Several projectile shapes have been considered to take into account the stress triaxiality effect on the failure mode during impact, penetration and perforation. The initial and residual velocities as well as the failure time have been measured during the tests to estimate more physical quantities. It has to be noticed that the failure time was defined using a High Speed Camera (HSC). Thanks to it, the impact forces (average and maximum level), were analyzed using numerical simulations together with an analytical description coupled to experimental observations. The key point of the model is the consideration of a shape function to define the pulse loading during perforation.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.4
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• pp.129-133
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• 2012

Coordinated multi-point transmission (CoMP) is a candidate technique for next generation cellular communications systems. One of the primary elements discussed in LTE-Advanced technology is CoMP, which can improve cell edge user data rate as well as spectral efficiency due to multiple input multiple output - orthogonal frequency division multiplex (MIMO-OFDM). We consider a system with multiple cells in which base stations coordinate with each other by sharing user channel state information (CSI), which mitigates inter cell interference (ICI), especially for users located at the cell edge. We introduce a new user scheduling method of ICI cancellation and the loss reduction of effective channel gain during the beamforming process, the proposed method improves the system sum rate, when compared to the conventional method by an average of 0.55bps/Hz in different number of total users per cell. It also outperforms the conventional method by approximately 0.38bps/Hz using different SNRs.

• Journal of Chest Surgery
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• v.53 no.2
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• pp.89-91
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• 2020

Bronchopulmonary sequestration (BPS) is a rare congenital abnormality of the lower airway, generally characterized by blood supply received from the systemic circulation. We present a rare case of a 19-year-old man with incidentally detected BPS supplied by a branch of a pulmonary artery, rather than a systemic artery. Computed tomography showed a sequestered segment supplied by a branch of the left pulmonary artery and containing an ectopic bronchus. As chest computed tomography revealed necrosis in the sequestered tissue, infection was presumed, and the tissue was surgically removed. This may represent a very unusual occurrence, as such cases have yet to be reported in the literature.

• Textile Coloration and Finishing
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• v.12 no.4
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• pp.256-263
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• 2000

A series of poly[3-methylene-3'-methylenesodiumbisulfite-bis(4-hydroxyphenyl) sulfone] (PMSBPS) was synthesized by the reaction of bis-(4-hydroxyphenyl)sulfone(BPS), formalin, and formaldehyde sodium bisulfite(FSB), and their effect on the staining of direct dye on nylon in the dyeing of nylon/cotton union fabric was investigated. PMSBPSes have good staining resist effect on nylon in the dyeing of nylon/cotton union. Prolonged reacting time between BPS and formalin is effective in improving the staining resist of final PMSBPS. Too many sulfonic acid groups than necessary in the PMSBPS increase the staining of nylon, presumably by increasing the solubility of PMSBPS. Staining resist effect of PMSBPS was evident in the measurement of color diffence of dyed goods.

• Korean Journal of Computational Design and Engineering
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• v.14 no.5
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• pp.338-345
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• 2009

c-PMS(collaborative project management system) is a business process(BP) based tool to manage collaborative projects which accomplish common business objectives determined by mutual agreement of companies using limited resources and time. This study analyzes collaborative BP, collaborative projects, and their relation, and proposes the architecture and operation scenario of c-PMS consisted of business process asset management(BPAM) sub-system and project manage(PM) sub-system. BPAM sub-system models private and public BP using a client/server based modeler, defines collaborative BPs process from public BPs, and manages them as companies' asset on a web portal. PM sub-system globally manages collaborative project using planning, execution, monitoring, and analyzing functions.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2687-2689
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• 2003

국내 LNG/LPG 누출을 관리할 수 있는 유무선 복합 종합관리시스템을 개발하였다. 이 시스템은 무선가스누출 탐지 및 제어부, 유선가스누출 탐지 및 제어부, 종합관리 시스템부로 구성되며, 특징으로는 무선가스누설 제어부 : 통신속도 1200bps, 유선가스누설 제어부 : 내부통신속도 9600 bps, IEEE 802 양방향 통신 방식, 최대전송속도 25 Mbps, 군 관리기능(server to server). 자체진단기능 등이다. 본 시스템을 가스공사 연구개발원 내에 운영되고 있는 CNG 및 LCNG 충전에 설치 운영하여 성능시험을 거친 결과, 현재까지 기존의 외국제품과 동등한 성능을 보이고 있으며 단가면에서도 2/3정도로 경쟁력을 가지고 있다. 보다 장기적인 현장적용 시험을 통해 성능 및 장기안정성 등이 확립되면 국내시장뿐만 아니라 수출을 통한 국제시장 점유도 기대할 수 있을 것이다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.1
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• pp.3-8
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• 2019

Osteonecrosis of the jaw (ONJ) is a well-known pathological condition in oncology derived from the use of bisphosphonates (BPs) and denosumab. Many molecular and immunological targets have been introduced for daily use in cancer treatment in recent years; consequently, new cases of ONJ have been reported in association with these drugs, especially if administered with BPs and denosumab. When the drugs are administered alone, ONJ is rarely seen. The objective of our study was to analyze the recent literature relative to the association of ONJ with these new drugs highlighting the pathogenic, clinical and therapeutic aspects. The close collaboration between maxillofacial surgeon, oncologist, dentist, and dental hygienist remains the most important aspect for the prevention, prompt recognition, and treatment of this pathology.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.5
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• pp.550-554
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• 2008

Bisphosphonates (BPs) are a class of agent used to treat patient with osteoporosis or malignant bone metastases. BPs can be categorized into 2 groups: nitrogen-containing and non-nitrogen containing. Nitrogen-containing BPs are considered to have more toxicity. Despite their clinical benefits, bisphosphonate-related osteonecrosis of jaw(BRONJ) is a significant complication to patients receveing these drugs. Since the first description of BRONJ in 2003 by Marx, the number of reports on BRONJ has been rapidly increasing. BRONJ is considered as an emerging problem in oral & maxillofacial surgery. Generally, osteonecrosis in the maxilla is rare, however BRONJ is found both in the maxilla and the mandible. This is an important feature of BRONJ compared to common infectious osteomyelitis of the jaw. Growing number of case reports, suggest that bisphosphonate therapy may cause exposed, necrotic bone. BRONJ has simillar features compared to IORN (infected osteoradionecrosis). BRONJ has meaningful features established through the interestigation on histopathologic and radiographic findings. These features have an impact on treatment plan and prognosis. This presentation contemplates on features of histopathologic and radiographic findings in bisphosphonate-related osteonecrosis of the jaw.

• Transactions of the Korean hydrogen and new energy society
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• v.21 no.1
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• pp.1-11
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• 2010

Current distribution measurement technique based on a segmented bipolar plate (BP) has been widely adopted to visualize the distribution of current density in a polymer electrolyte membrane. However, a concern is raised how closely the current density of a segmented BP can approach that of a corresponding non-segmented membrane. Therefore, in this paper, the accuracy of the measurement technique is numerically evaluated by applying a three-dimensional, two-phase fuel cell model to a $100\;cm^2$ area fuel cell geometry in which segmented BPs and non-segmented membrane are combined together. The simulation results reveal that the errors between the current densities of the segmented BPs and non-segmented membrane indeed exist, predicting the maximum relative error of 33% near the U-turn regions of the flow-field. The numerical study further illustrates that the erroneous result originates from the BPs segmented non-symmetrically based on the flow channels that allows some currents bypassing flow channels to flow into its neighboring segment. Finally, this paper suggests the optimal way for bipolar plate segmentation that can minimize the deviation of current measured in a segmented BP from that of a corresponding membrane region.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.3
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• pp.152-159
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• 2012

Objectives: This study evaluated bisphosphonate-related osteonecrosis of the jaws (BRONJ) in patients diagnosed with malignant bone tumors. Demographic findings, laboratory, and radiographic analyses were performed to characterize disease severity and progression. Materials and Methods: Patients who had been diagnosed with BRONJ (2005-2010) at the authors' hospital according to the American Association of Oral and Maxillofacial Surgeons were investigated. Twenty-one patients (12 with multiple myelomas, 7 with breast cancer, and 2 with prostate cancer) who had been treated with bisphosphonates (BPs) for malignant bone tumors were included. Radiographic evaluations with a panorama, computed tomography, whole body bone scan, and laboratory findings were evaluated for erythrocyte sedimentation rate (ESR), c-reactive proteins (CRPs), and c-terminal cross-linked telopeptides (CTXs). Results: The average age of the patients was 64.3 (range 51-80), and they were treated with BPs for an average of $35{\pm}19$ months before BRONJ was diagnosed. Types of BPs were zolendronic acid (81%, intravenous [IV]), pamidronate (4.8%, IV), zoledronic acid+pamidronate (4.8%, IV), alendronate (4.8%, per os [PO]), and ibadronate (4.75%, PO). Extraction (67%) and persistent irritation of dentures (20%) were the most common triggering factors. BRONJ in the mandible was reported in 62% of the cases, in the maxilla 24%, and both 14%. BRONJ occurred more frequently in patients with multiple myelomas (n=12, 57.1%). Most of the patients revealed an advanced BRONJ stage; Stage I (n=2, 9%), Stage II (n=13, 62%), and Stage III (n=6, 29%). Conclusion: The differences of the ESR, CRP, and CTX values between the BRONJ-recurring and non-recurring patients after the treatment were not evident. Later stage BRONJ patients showed lower CTX levels. A drug holiday after the diagnosis of BRONJ did not remarkably influence the surgical outcomes. However, the limited number of patients in the study should be considered.