• Nuclear Engineering and Technology
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• 제54권10호
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• pp.3816-3823
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• 2022

This work analyzed the dosimetric difference between the intensity modulated radiotherapy (IMRT), partial/single/double-arc volumetric modulated arc therapy (PA/SA/DA-VMAT) techniques in treatment planning for treating more than one target of lung cancer at different isocenters. IMRT and VMAT plans at different isocenters were created systematically using a Harold heterogeneous lung phantom. The conformity index (CI), homogeneity index (HI), gradient index (GI), dose-volume histogram and mean and maximum dose of the PTV were calculated and analyzed. Furthermore, the dose-volume histogram and mean and maximum doses of the OARs such as right lung, contralateral lung and non GTV were determined from the plans. The IMRT plans showed the superior target dose coverage, higher mean and maximum values than other VMAT techniques. PA-VMAT technique shows more lung sparing and DA-VMAT increases the V_5/10/20 values of contralateral lung than other VMAT and IMRT techniques. The IMRT technique achieves highly conformal dose distribution to the target than other VMAT techniques. Comparing to the IMRT plans, the higher V_5/10/20 and mean lung dose were observed in the contralateral lung in the DA-VMAT.

• 한국의학물리학회지:의학물리
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• 제23권2호
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• pp.99-105
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• 2012

치료 테이블 회전, 아크 간 콜리메이터 회전 각도가 광자에너지별 전립선암 래피드아크 치료계획의 선량분포에 미치는 영향에 대해 조사하였다. 6 MV와 10 MV 광자 에너지에 대해 2 아크(two arcs)를 사용하여 아크 간 콜리메이터 각도 차이가 $0^{\circ}$, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $75^{\circ}$, $90^{\circ}$인 경우와 치료 테이블 회전 유무에 따라 치료계획을 시행하였다. 선량 최적화를 위한 표적 및 중요 장기의 선량 제한치(dose constraints)를 동일하게 적용하여 계산하였고 선량 분포를 평가하기 위해 CI (Conformity index), HI (Homogeneity index), QOC (Quality of Coverage) 등의 정량화된 선량 지표를 구하여 각 치료계획의 최적화 결과를 비교하였다. 그 결과 치료계획표적용적과 중요장기의 선량 지표 차이는 3.6% 이하로 광자에너지, 치료테이블, 아크 간 콜리메이터 각도의 영향은 크지 않았다. 그러나 표적에서 먼 정상조직의 경우 저 선량 영역 차이가 크게 나타났다. 좌우 대퇴골두의 V15%는 6 MV 일 때 각각 6.4%, 5.5% 높았고, 치료테이블 회전 시에는 23.4%, 24.1% 높게 나타났다. 표적에서 먼 영역(Far Region)의 V10%는 6 MV 일 때 54.2 cc, 치료테이블 회전이 없을 때 343.4 cc, 아크 간 콜리메이터 각도가 $0^{\circ}$일 때 457.8 cc 크게 나타났다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권9호
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• pp.3885-3906
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• 2020

Hybrid fuzzing which combines fuzzing and concolic execution, has proved its ability to achieve higher code coverage and therefore find more bugs. However, current hybrid fuzzers usually suffer from inefficiency and poor scalability when applied to complex, real-world program testing. We observed that the performance bottleneck is the inefficient cooperation between the fuzzer and concolic executor and the slow symbolic emulation. In this paper, we propose a novel solution named EPfuzzer to improve hybrid fuzzing. EPfuzzer implements two key ideas: 1) only the hardest-to-reach branch will be prioritized for concolic execution to avoid generating uninteresting inputs; and 2) only input bytes relevant to the target branch to be flipped will be symbolized to reduce the overhead of the symbolic emulation. With these optimizations, EPfuzzer can be efficiently targeted to the hardest-to-reach branch. We evaluated EPfuzzer with three sets of programs: five real-world applications and two popular benchmarks (LAVA-M and the Google Fuzzer Test Suite). The evaluation results showed that EPfuzzer was much more efficient and scalable than the state-of-the-art concolic execution engine (QSYM). EPfuzzer was able to find more bugs and achieve better code coverage. In addition, we discovered seven previously unknown security bugs in five real-world programs and reported them to the vendors.

• Molecules and Cells
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• 제20권2호
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• pp.201-209
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• 2005

We have constructed an AFLP-based linkage map of Japanese red pine (Pinus densiflora Siebold et Zucc.) using haploid DNA samples of 96 megagametophytes from a single maternal tree, selection clone Kyungbuk 4. Twenty-eight primer pairs generated a total of 5,780 AFLP fragments. Five hundreds and thirteen fragments were verified as genetic markers with two alleles by their Mendelian segregation. At the linkage criteria LOD 4.0 and maximum recombination fraction 0.25(${\theta}$), a total of 152 markers constituted 25 framework maps for 19 major linkage groups. The maps spanned a total length of 2,341 cM with an average framework marker spacing of 18.4 cM. The estimated genome size was 2,662 cM. With an assumption of equal marker density, 82.2% of the estimated genome would be within 10 cM of one of the 230 linked markers, and 68.1% would be within 10 cM of one of the 152 framework markers. We evaluated map completeness in terms of LOD value, marker density, genome length, and map coverage. The resulting map will provide crucial information for future genomic studies of the Japanese red pine, in particular for QTL mapping of economically important breeding target traits.

• 한국의학물리학회지:의학물리
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• 제31권4호
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• pp.153-162
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• 2020

Purpose: We aim to evaluate the accuracy and effectiveness of an automatically converted radiation therapy plan between Radixact machines by comparing the original plan with the transferred plan. Methods: The study involved a total of 20 patients for each randomly selected treatment site who received radiation treatment with Radixact. We set up the cheese phantom (Gammex RMI, Middleton, WI, USA) with an Exradin A1SL ion chamber (Standard Imaging, Madison, WI, USA) and GAFCHROMIC EBT3 film (International Specialty Products, Wayne, NJ, USA) inserted. We used three methods to evaluate an automatically converted radiation therapy plan using the features of the Plan transfer. First, we evaluated and compared Planning target volume (PTV) coverage (homogeneity index, HI; conformity index, CI) and organs at risk (OAR) dose statistics. Second, we compared the absolute dose using an ion chamber. Lastly, we analyzed gamma passing rates using film. Results: Our results showed that the difference in PTV coverage was 1.72% in HI and 0.17% in CI, and majority of the difference in OAR was within 1% across all sites. The difference (%) in absolute dose values was averaging 0.74%. In addition, the gamma passing rate was 99.64% for 3%/3 mm and 97.08% for 2%/2 mm. Conclusions: The Plan transfer function can be reliably used in appropriate situations.

• 수산해양기술연구
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• 제60권1호
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• pp.47-56
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• 2024

After the United Nations Convention on the Law of the Sea (UNCLOS) and the United Nations Fish Stocks Agreement (UNFSA) came into effect, international cooperation through Regional Fisheries Management Organizations (RFMOs) was required, and each RFMO established and adopted the Conservation and Management Measure (CMM) for the regional Observer Programs to collect data on fishing activities and biological information and to monitor compliance with its CMMs. The observer coverage required by RFMO is set differently for each organization, ranging from 5% to 100%. In addition, tuna-RFMOs recommend increasing observer coverage in longline fisheries by at least 20% for reliable quantitative analysis of not only target species but also bycatch species and ecologically related species such as sharks, seabirds, sea turtles, and marine mammals. Therefore, in this study, we discussed ways to improve the national observer programs of Korean distant water fisheries that should be addressed in the future to respond to the RFMO trends.

• 한국환경복원기술학회지
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• 제20권5호
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• pp.43-58
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• 2017

This study aims to provide basic understanding for evaluating the quantitative and qualitative progress of national protected areas, through the theoretical review of Aichi Biodiversity Target 11 in order to comply with recommendations of international community and to conserve biodiversity. As a result of the study, Aichi Biodiversity Target 11 sets out the specific contents that the Parties should achieve for protected areas by identifying them as temporal and spatial goals. The temporal goal, the time schedule for achieving the goal, is 2020, and the spatial goal is divided into quantitative expansion goals and qualitative improvement goals. The quantitative expansion goals present the target coverage of protected areas separately terrestrial and marine. The qualitative improvement goals include the target areas for conservation and five conservation considerations. The conservation targets focus on the important areas with regard to biodiversity and ecosystem services. The five conservation considerations mean effective management, equitable management, ecological representativeness, connectivity, and integration into the landscape and seascape for protected areas. Finally, it suggests that two tracks of protected areas and other effective area-based conservation measures(OECMs) should be used as conservation measures to build an integrated system. The results of this study can be applied to quantitative and qualitative evaluation methods for protected areas and it can contribute to achieve quantitative expansion goals and qualitative improvement goals for them.

• 정보처리학회논문지B
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• 제16B권1호
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• pp.79-84
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• 2009

이 논문은 한국어 문장을 대상으로 구문요소의 전치를 기반으로 한 문서 워터마킹 방법을 제안한다. 한국어와 같은 교착어는 구문요소의 순서가 자유롭기 때문에 구문 트리 기반의 자연어 워터마킹을 위한 좋은 환경을 제공한다. 본 논문에서 제안하는 자연어 워터마킹 방법은 7단계로 구성되어 있다. 첫째, 문장의 구문분석을 수행한다. 다음으로, 구문요소가 해당 절의 범위 안에서만 전치되도록 범위를 한정하기 위하여 구문 트리로부터 각 절을 분할한다. 세 번째로, 전치를 위한 목표 구문요소를 선택한다. 네 번째, 목표 구문요소의 전치 후에도 문장의 의미나 문체의 변화가 최소화되도록 가장 자연스러운 전이위치를 결정한다. 그 후, 목표 구문요소에 대한 워터마크 비트를 삽입한다. 여섯 번째 단계로, 워터마크 비트가 목표 구문요소의 전치 방향과 상응하지 않으면 구문 트리에서 목표 구문요소를 전치한다. 마지막으로 변환된 구문 트리에서 워터마킹된 문서를 얻는다. 실험 결과를 통해 본 논문에서 제안한 방법의 적용률은 91.53%이고, 최종 워터마킹된 문장들 중 부자연스러운 문장의 비율은 23.16%로서 기존 시스템들보다 좋은 결과를 보여준다. 또한 워터마킹된 문장이 원시 문장과 같은 문체를 유지하고, 의미적인 왜곡없이 같은 정보를 나타내고 있다.

• 산학경영연구
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• 제20권1호
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• pp.145-168
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• 2007

전자상거래에서 거래되는 상품들에 대한 고객의 선호도를 사전에 파악하여 고객이 자신의 취향에 적합한 상품을 쉽게 찾도록 도와주고 전자상거래에 업체에 있어서는 목표고객의 설정을 자동적으로 처리할 수 있는 시스템이 추천시스템이다. 추천시스템은 고객과 업체 모두에게 이득을 가져올 수 있는 시스템으로 현재 많은 전자상거래 업체들이 적용 중에 있다. 본 연구는 전자상거래에서 널리 이용되고 있는 협력적 추천기법을 이용하여 고객 선호도 예측의 정확도를 향상시키기 위하여 고객들간의 선호도 유사 정도를 나타내는 유사도 가중치에 일정 범위의 임계치를 설정하였다. 임계치의 설정에 따라 선호도 예측의 정확도가 향상되었으나 임계치의 설정 범위에 따라 고객 선호도를 예측할 수 있는 비율이 감소함을 알 수 있었으며 이에 따라 추천을 할 수 없는 고객이 발생할 수 있음을 알 수 있었다. 결과를 바탕으로 고객에 대한 추천과 예측의 정확도를 동시에 고려하는 임계치 설정에 대하여 더 많은 연구가 필요하다는 것을 알 수 있었다.

• Journal of Electrical Engineering and Technology
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• 제13권4호
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• pp.1504-1514
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• 2018

The objective of this study is to compare the suitability of a non-parametric and 3 parametric distributions in the characterization of prediction intervals of photovoltaic power forecasts with high confidence levels. The prediction intervals of the forecasts are calculated using a method based on recent past data similar to the target forecast input data, and on a distribution assumption for the forecast error. To compare the suitability of the distributions, prediction intervals were calculated using the proposed method and each of the 4 distributions. The calculations were done for one year of day-ahead forecasts of hourly power generation of 432 PV systems. The systems have different sizes and specifications, and are installed in different locations in Japan. The results show that, in general, the non-parametric distribution assumption for the forecast error yielded the best prediction intervals. For example, with a confidence level of 85% the use of the non-parametric distribution assumption yielded a median annual forecast error coverage of 86.9%. This result was close to the one obtained with the Laplacian distribution assumption (87.8% of coverage for the same confidence level). Contrasting with that, using a Gaussian and Hyperbolic distributions yielded median annual forecast error coverage of 89.5% and 90.5%.