• Journal of Photoscience
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• 제2권2호
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• pp.99-101
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• 1995

A semiempirical methods(PM3-CI-UHF, MM2) for the evaluation of ground and excited state electronic structures of electron-donating substituents are applied to 4, 5', 8-trimethylpsoralen(TMP) with TMP dimer. Three types of product have been proposed; (1) pyrone< >pyrone, (2) pyrone< >furan, (3) hetero dimer resulting from the C$_4$-cycloaddition between the furan end of one TMP moiety and the pyrone end of the other, with cis-syn configuration.

• 한국통신학회:학술대회논문집
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• 한국통신학회 2006년도 하계종합학술발표회 논문 초록집
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• pp.733-733
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• 2006

• 대한방사선치료학회:학술대회논문집
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• 대한방사선치료학회 2005년도 춘계학술대회 초록집
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• pp.33-34
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• 2005

• 대한족부족관절학회지
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• 제23권3호
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• pp.91-99
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• 2019

Purpose: This retrospective study reports the intermediate-term clinical outcomes including the practical function in daily and sports activities after total ankle arthroplasty for end-stage rheumatoid arthritis, as well as the effects of modification of perioperative anti-rheumatic medications. Materials and Methods: Twelve patients were followed for a minimum of 2 years after total ankle replacement for end-stage rheumatoid arthritis. Perioperative anti-rheumatic medications in all patients were modified based on a specific guideline. Clinical evaluations consisted of American Orthopaedic Foot and Ankle Society (AOFAS) scores, Foot and Ankle Outcome Score (FAOS), and Foot and Ankle Ability Measure (FAAM) scores. Periodic radiographic evaluation was conducted to detect changes in ankle alignment and postoperative complications. Results: Mean AOFAS, FAOS, and FAAM scores improved significantly from 37.5 to 81.2, 39.1 to 72.4, and 33.8 to 64.0 points at final follow-up, respectively (p<0.001). Functional outcomes in daily and sports activities at final follow-up were found to be 76.5 and 55.8 points for the FAOS and 70.5 and 57.5 points for the FAAM, respectively. As early postoperative complications, there was one case of local wound necrosis, one case of medial malleolar fracture, and one case of deep peroneal nerve injury. Radiological evaluation revealed two cases of asymptomatic heterotopic ossification and one case of progressive arthritis in the talonavicular joint. Reoperation was performed in only one patient (8.3%) with a medial soft tissue impingement at a mean of 35.6 months follow-up. Conclusion: Total ankle arthroplasty appears to be an effective surgical option for end-stage rheumatoid arthritis. Practical functions in daily and sports activities were significantly improved at intermediate-term follow-up. Modification of perioperative anti-rheumatic medications can be one of the solutions to reduce the postoperative complication rate.

• 한국멀티미디어학회논문지
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• 제20권5호
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• pp.827-834
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• 2017

Android's inter-application access enriches its application ecosystem. However, it exposes security vulnerabilities where end-user data can be exploited by attackers. While existing techniques have focused on minimizing the risks of inter-application access, they either suffer from inaccurate risk detection or are primarily available to expert users. This paper introduces a novel technique that automatically analyzes potential risks between a set of applications, aids end-users to effectively assess the identified risks by crowdsourcing assessments, and generates an access control policy which prevents unsafe inter-application access at runtime. Our evaluation demonstrated that our technique identifies potential risks between real-world applications with perfect accuracy, supports a scalable analysis on a large number of applications, and successfully aids end-users' risk assessments.

• 한국구조물진단유지관리공학회 논문집
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• 제21권5호
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• pp.74-82
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• 2017

강교량은 유지관리가 충분히 이루어지지 않거나, 해안 과 같이 가설위치의 환경이 고온 다습한 경우 단면에 국부적인 부식손상이 발생할 수 있다. 특히 강거더 교량 의 지점부에서는 교대부와 강거더 단부의 공간이 협소하여 상대적으로 습도가 높고 신축이음부로부터의 강우 및 동결 방지제가 누수되어 침전물을 습윤상태로 유지하게 되므로, 복부판과 지점부 보강재에 집중적으로 부식이 발생되고 있으므로 이로인한 구조성능 변화를 확인하여야 한다. 따라서 본 연구에서는 실제 발생할 수 있는 강거더 단부 복부판과 보강재의 국부부식손상을 모사한 강재 실험체를 제작하고 이에 대한 단부 지압강도 변화를 실험적으로 평가하였다. 실험결과, 국부적 부식손상은 강거더 단부의 지압강도에 영향을 주며, 특히 수직 보강재에 의한 영향이 크게 나타남을 확인하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.89-98
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• 2005

Preliminary pile load tests for the design of large diameter drilled shaft were performed on two of reduced scale(D=1370mm) test piles. The maximum loads of 2350 tonf in each direction were applied using bi-directional hydraulic jacks(Osterberg Cell) at toe. Neither of the test piles yielded in terms of skin friction and end bearing. Comparisons of the test results with several methods that estimate pile capacity show that the method of Horvath and Kenney(1979) for skin friction and Zhang and Einstein(1998) for end bearing were most appropriate for the site. The test results were directly applied to pile design in case RQD of skin and toe was larger than that of the test pile. It is desirable, therefore, to consider not only unconfined compression strength but also rock mass properties(i.e. TCR, RQD) for skin friction and end bearing evaluation in the future.

• Journal of Positioning, Navigation, and Timing
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• 제6권1호
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• pp.1-8
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• 2017

In this study, to design a multi-GNSS receiver using single RF front-end, the receiving performances for various frequency plans were evaluated. For the fair evaluation and comparison of different frequency plans, the same signal needs to be received at the same time. For this purpose, two synchronized RF front-ends were configured using USRP X310, and PC-based software was implemented so that the quality of the digital IF signal received at each front-end could be evaluated. The software consisted of USRP control, signal reception, signal acquisition, signal tracking, and C/N0 estimation function. Using the implemented software and USRP-based hardware, the signal receiving performances for various frequency plans, such as the signal attenuation status, overlapping of different systems, and the use of imaginary or real signal, were evaluated based on the C/N0 value. The results of the receiving performance measurement for the various frequency plans suggested in this study would be useful reference data for the design of a multi-GNSS receiver in the future.

• 한국전자통신학회논문지
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• 제6권1호
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• pp.49-54
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• 2011

본 논문에서는 대규모 MANET을 대상으로 VoIP 트래픽의 종단간 성능을 측정하고 분석하여 보았다. 측정된 결과의 분석을 통하여 대규모 MANET에서 사용 가능한 VoIP 구현조건을 제시하였다. 성능측정은 NS-2 네트워크 시뮬레이터를 기반으로 제작한 VoIP 시뮬레이터를 사용하였다. 시뮬레이션을 통하여 접속품질로서 호연결율, 전송품질로서 MOS, 네트워크지연, 그 이외의 평가척도로서 패킷손실율을 측정하였다. 본 논문의 결과로서 대규모 MANET에서 VoIP 구축과 운영에 적합한 조건이 단일 네트워크 규모로 최대 $10{\sim}15km^2$이내, 노드수 로 500여개, 호연결수로 100여개임을 확인하였다.

• 한국세라믹학회지
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• 제45권1호
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• pp.75-81
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• 2008

In this study, machining characteristics of AIN-hBN composites were evaluated in end-milling process. As a first step, AIN-hBN composite specimens with various hBN contents were prepared using hot press method. Material properties of the composites, such as relative density, Young's modulus and fracture toughness, were measured and compared. Then, a series of end-milling experinients were performed under various cutting conditions by changing cutting speed, depth-of-cut and feed rate. Cutting force variations were measured using a tool dynamometer during the cutting experiments. Machined surfaces of the specimens were observed using SEM and a surface pro filer to investigate the surface integrity changes. The cutting force decreased with an increases of hBN content. The cutting process was almost impossible for monolithic AIN, owing to severe chipping. In contrast, at high content of hBN, surface damage and chipping decreased, and better surface roughness can be obtained.