• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
• /
• pp.328-330
• /
• 2003

The land cover of burned area has changed dramatically since Daxinganling forest fire in Northeastern China during May 6 ? June 4, 1987. This research focused on determining the burn severity and assessment of forest recovery. Burned severity was classified into three levels from June 1987 Landsat TM data acquired just after the fire. A regression model was established between the forest canopy closure from 1999 forest stand map and the NDVI values from June 2000 Landsat ETM+ data. The map of canopy closure was got according to the regression model. And vegetation cover was classified into four types according to forest closure density. The change matrix was built using the classified map of burn severity and vegetation recovery. Then the change conversions of every forest type were analyzed. Results from this research indicate: forest recovery status is well in most of burned scars; and vegetation change detection can be accomplished using postclassification comparison method.

• Genomics & Informatics
• /
• 제6권2호
• /
• pp.91-94
• /
• 2008

Single nucleotide polymorphisms (SNPs) are the most abundant form of human genetic variation and are a resource for mapping complex genetic traits. A genome is covered by millions of these markers, and researchers are able to compare which SNPs predominate in people who have a certain disease. The International HapMap Project, launched in October, 2002, motivated us to start the Korean HapMap Project in order to support Korean HapMap infrastructure development and to accelerate the finding of genes that affect health, disease, and individual responses to medications and environmental factors. A Korean SNP and haplotype database system was developed through the Korean HapMap Project to provide Korean researchers with useful data-mining information about disease-associated biomarkers for studies on complex diseases, such as diabetes, cancer, and stroke. Also, we have developed a series of software programs for association studies as well as the comparison and analysis of Korean HapMap data with other populations, such as European, Chinese, Japanese, and African populations. The developed software includes HapMapSNPAnalyzer, SNPflank, HWE Test, FESD, D2GSNP, SNP@Domain, KMSD, KFOD, KFRG, and SNP@WEB. We developed a disease-related SNP retrieval system, in which OMIM, GeneCards, and MeSH information were integrated and analyzed for medical research scientists. The kHapMap Browser system that we developed and integrated provides haplotype retrieval and comparative study tools of human ethnicities for comprehensive disease association studies (http://www.khapmap.org). It is expected that researchers may be able to retrieve useful information from the kHapMap Browser to find useful biomarkers and genes in complex disease association studies and use these biomarkers and genes to study and develop new drugs for personalized medicine.

• 한국컴퓨터정보학회지
• /
• 제14권1호
• /
• pp.265-271
• /
• 2006

F-HMIPv6(Fast-Hierarchical Mobile IP version 6) 네트워크에서는 단말의 이동을 관리하기 위해 MAP(Mobility Anchor Point)를 사용한다. 현재는 매크로 핸드오프 발생 시 단말로부터 가장 멀리 떨어져있는 MAP을 선택하는 기법을 사용하고 있다. 그러나 이 경우 하나의 큰 MAP으로 전체 부하가 몰리는 문제와 이동 단말과 MAP간의 긴 거리로 인해 통신 비용이 증가하는 문제가 있다. 이 연구에서는 단말의 이동속도와 패킷 전송률을 고려하여 통신 비용을 최소화 하는 비용 효율적인 MAP을 선택 기법을 제안한다. 이를 위해 통신 비용을 바인딩 업데이트 비용과 데이터 패킷 전달 비용으로 구분하고 이 통신 비용을 최소화하는 MAP의 크기를 수식으로 표현한다.

• 한국방송∙미디어공학회:학술대회논문집
• /
• 한국방송공학회 2014년도 하계학술대회
• /
• pp.81-83
• /
• 2014

본 논문에서는 3 차원 영상시스템의 성능향상을 위한 깊이영상의 여러 후처리 필터들의 성능을 비교 실험한다. 성능비교를 위해 현재 3D-ATM 에 쓰이고 있는 dilation 필터와, 경계값 보존에 탁월한 성능을 보이는 bilateral 필터, 그리고 깊이영상의 특성을 이용한 depth boundary reconstruction 필터를 선정하였다. 본 논문에서는 위 제시한 필터들의 특징에 대하여 소개하고, 이들 필터들이 3 차원 영상 시스템의 깊이영상에 적용되었을 때 어느정도 성능향상을 보이는지 비교 분석한다.

• 한국의학물리학회지:의학물리
• /
• 제28권2호
• /
• pp.61-66
• /
• 2017

The aim of this study is to investigate the characteristics of portal dosimetry in comparison with the MapCHECK2 measurments. In this study, a total of 65 treatment plans including both volumetric modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT) were retrospectively selected and analyzed (45 VMAT plans and 20 IMRT plans). A total of 4 types of linac models (VitalBeam, Trilogy, Clinac 21EXS, and Clianc iX) were used for the comparison between portal dosimetry and the MapCHECK2 measurements. The VMAT plans were delivered with two VitalBeam linacs (VitalBeam1 and VitalBeam2) and one Trilogy while the IMRT plans were delivered with one Clinac 21EXS and one Clinacl iX. The global gamma passing rates of portal dosimetry and the MapCHECK2 measurements were analyzed with a gamma criterion of 3%/3 mm for IMRT while those were analyzed with a gamma criterion of 2%/2 mm for VMAT. Spearman's correlation coefficients (r) were calculated between the gamma passing rates of portal dosimetry and those of the MapCHECK2 measurements. For VMAT, the gamma passing rates of portal dosimetry with the VitalBeam1, VitalBeam2, and Trilogy were $97.3%{\pm}3.5%$, $97.1%{\pm}3.4%$, and $97.5%{\pm}1.9%$, respectively. Those of the MapCHECK2 measurements were $96.8%{\pm}2.5%$, $96.3%{\pm}2.7%$, and $97.4%{\pm}1.3%$, respectively. For IMRT, the gamma passing rates of portal dosimetry with Clinac 21EXS and Clinac iX were $99.7%{\pm}0.3%$ and $99.8%{\pm}0.2%$, respectively. Those of the MapCHECK2 measurements were $96.5%{\pm}3.3%$ and $97.7%{\pm}3.2%$, respectively. Except for the result with the Trilogy, no correlations were observed between the gamma passing rates of portal dosimetry and those of the MapCHECK2 measurements. Therefore, both the MapCHECK2 measurements and portal dosimetry can be used as an alternative to each other for patient-specific QA for both IMRT and VMAT.

• 제어로봇시스템학회논문지
• /
• 제17권1호
• /
• pp.47-53
• /
• 2011

To enable the efficient operation of ITS, it is necessary to collect location data for vehicles on the road. In the case of futuristic transportation systems like ubiquitous transportation and smart highway, a method of data collection that is advanced enough to incorporate road lane recognition is required. To meet this requirement, technology based on radio frequency identification (RFID) has been researched. However, RFID may fail to yield accurate location information during high-speed driving because of the time required for communication between the tag and the reader. Moreover, installing tags across all roads necessarily incurs an enormous cost. One cost-saving alternative currently being researched is to utilize GNSS (global navigation satellite system) carrierbased location information where available. For lane recognition using GNSS, a precise digital map for determining vehicle position by lane is needed in addition to the carrier-based GNSS location data. A "precise digital map" is a map containing the location information of each road lane to enable lane recognition. At present, precise digital maps are being created for lane recognition experiments by measuring the lanes in the test area. However, such work is being carried out through comparison with vehicle driving information, without definitions being established for detailed performance specifications. Therefore, this study analyzes the performance requirements of a precise digital map capable of lane recognition based on the accuracy of GNSS location information and the accuracy of the precise digital map. To analyze the performance of the precise digital map, simulations are carried out. The results show that to have high performance of this system, we need under 0.5m accuracy of the precise digital map.

• Spatial Information Research
• /
• 제6권2호
• /
• pp.201-216
• /
• 1998

건설교통부는 국가지리정보체계구축사업(NGIS)의 일환으로 수치지형도 제작사업을 1998년 말까지 완료할 예정이며, 특히 1:1,000 수치지형도는 지방자치단체의 GIS 기본도로 사용될 예정이다. 그러나 1:1,000 수치지형도에는 많은 지방정부들의 행정업무에 필요한 지적이나 도시계획과 같은 무형의 정보들은 포함되어 있지 않다. GIS사업의 활성화를 위해 지적도의 전산화 작업이 시급한 실정이다. 본 연구는 수치지형도와 지적의 불부합 원인을 분석하고, 정확도가 다른 두 데이타를 일치시키는 GIS의 기술적 방법들을 검토하고 서울시를 예로하여 도시계획관련부서의 지적데이타에 대한 수요를 분석하여 수치지형도와 중첩하여 활용할 수 있는 지적도 도형자료의 구축지침을 제시하였다. 그리고 제작지침 제시를 위해 서울시 중구 황학동, 신당동, 그리고 종로구 승인동 일부지역에 대한 편집지적 데이터를 구축하였다.

• 한국콘텐츠학회:학술대회논문집
• /
• 한국콘텐츠학회 2014년도 춘계 종합학술대회 논문집
• /
• pp.19-20
• /
• 2014

• 제어로봇시스템학회논문지
• /
• 제15권4호
• /
• pp.451-455
• /
• 2009

This paper provides a comparison of global path planning method in single string by using pulled and pushed SOFM (Self-Organizing Feature Map) which is a method among a number of neural network. The self-organizing feature map uses a randomized small valued initial-weight-vectors, selects the neuron whose weight vector best matches input as the winning neuron, and trains the weight vectors such that neurons within the activity bubble are move toward the input vector. On the other hand, the modified SOFM method in this research uses a predetermined initial weight vectors of the one dimensional string, gives the systematic input vector whose position best matches obstacles, and trains the weight vectors such that neurons within the activity bubble are move toward or reverse the input vector, by rising a pulled- or a pushed-SOFM. According to simulation results one can conclude that the modified neural networks in single string are useful tool for the global path planning problem of a mobile robot. In comparison of the number of iteration for converging to the solution the pushed-SOFM is more useful than the pulled-SOFM in global path planning for mobile robot.

• 천문학회보
• /
• 제39권2호
• /
• pp.45.2-45.2
• /
• 2014

To measure the mass distribution of galaxy systems weak-lensing analysis has been widely used because it directly measures the total mass of a system regardless of its baryon content and dynamical state. However, the weak-lensing only provides a map of projected surface mass density. On the other hand, galaxy redshift surveys provide a map of the three-dimensional galaxy distribution. It thus can resolve the structures along the line of sight projected in the weak-lensing map. Therefore, the comparison of structures identified in the weak-lensing maps and in the redshift surveys is an important test of the issues limiting applications of weak-lensing to the identification of galaxy clusters. Geller et al. (2010) and Kurtz et al. (2012) compared massive clusters identified in a dense redshift survey with significant weak-lensing map convergence peaks. Both assessments of the efficiency of weak-lensing map for cluster identification did not draw a general conclusion, because the sample is so small. Thus, we additionally perform deep imaging observations of fields in a dense galaxy redshift survey that contain galaxy clusters at z~0.2-0.5, using CFHT Megacam.