• Title/Summary/Keyword: Topographic Features

Search Result 148, Processing Time 0.03 seconds

Clinicopathological Features of Colon Adenocarcinoma in Qazvin, Iran: A 16 Year Study

  • Hajmanoochehri, Fatemeh;Asefzadeh, Saeed;Kazemifar, Amir Mohammad;Ebtehaj, Mehdi
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.2
    • /
    • pp.951-955
    • /
    • 2014
  • Background: Colorectal cancer (CRC) was the fourth most commonly diagnosed cancer in Iran between 2000 and 2009, with adenocarcinoma (AC) as the most common histological type. Demographic, topographic and histological variables are important in the epidemiology and biology of cancer. The aim of this study was to investigate clinicopathological features of colon adenocarcinomas in Qazvin, Iran. Materials and Methods: With a retrospective design, patient records of two pathology wards from March 1997 to March 2013 were studied with regard to anatomical location and histological classification. A broader anatomical grouping was also used including distal vs proximal regions and right sided vs left sided tumors. Data were analyzed using T-test and chi-square test. Results: 118 (50.9%) male and 114 (49.1%) female patients were included in the study. Mean age was $57.3{\pm}14.7$ years, with 29.2% under 50 years. There was no significant gender difference for age at diagnosis. The rectum (56%) and sigmoid colon (25%) were the most frequent anatomical locations. Proximal cases accounted for 18.6% in males and 8.8% in females (p=0.02). AC was more prevalent than other usual types in younger patients. The proportion of proximal cancer was 1.7% in first eight years of the study period vs 12.1% in the second one (p=0.005). A similar trend was also seen in right sided colon cancers (p=0.018). Conclusions: Young people are also at risk for the cancer with poor prognosis. Screening programs and weight loss in obese individuals can reduce incidence and complications of CRC.

Study on the Accuracy Improvement for Survey of Estuary Riverbed (하구하상 측량 정밀도 향상에 관한 연구)

  • 박운용;김천영;김용보
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.21 no.2
    • /
    • pp.137-145
    • /
    • 2003
  • Currently, the availability of 3-D topographical survey by combination of GPS and Echo Sounder has been increased in the various field like as the construction of structure, the dredging and the reclamation in the ocean and river, and observation of topographic change in seabed or riverbed. In this case, the error of depth sounding can divide in form that is happened by combination of GPS and Echo Sounder, and form that is happened in Echo Sounder itself, In this study, in the case happen by Echo Sounder itself, analyzed error by specially about geological features of the seabed and riverbed that is specular surface of sound wave and wished to present solution way. The sounding error about the echo sounder and characteristic of estuary riverbed was found by understanding the relation of average diameter and residual error and we defined correction formula, Y=-0.00474$^{*}$In(X) -0.0045 by the regression analysis. and then we verified applicability of correction formula. As the result, if measure Preliminary investigation or pre-survey the geological features for the survey area at topographical survey of estuary riverbed, we presented the error correction formula that estimate and can correct of error by Echo Sounderer.

Construction and Application of 3D Image Model for GIS Spatial Analysis (GIS 공간분석을 위한 3D 영상모형의 구축과 활용)

  • Jung, Sung-Heuk;Lee, Kae-Dong;Lee, Jae-Kee
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.26 no.6
    • /
    • pp.561-569
    • /
    • 2008
  • Currently, satellite image, aerial image and airborne laser scanning data are mostly used to build 3D image models. However, we are in need of quality 3D image models as current models cannot express topographic and features most elaborately and realistically. When making 3D image models, the model is first built and textures from terrestrial photos are applied to add realistic features to the model. This study analyzed techniques to use photogrammetry and laser scanning data to create a 3D image models with topography, building and statue that emphasize spatial accuracy, delicate depiction and photo-realistic imaging. 3D image models with spatial accuracy and photographic texture were built to be served via 3D image map services systems on the internet. The 3D image models can be used for various purposes, such as daylight and view right analysis, landscape analysis, facility management system.

Estimation of fractal dimension for Seolma creek experimental basin on the basis of fractal tree concept (Fractal 나무의 개념을 기반으로 한 설마천 시험유역의 Fractal 차원 추정)

  • Kim, Joo-Cheol;Jung, Kwan Sue
    • Journal of Korea Water Resources Association
    • /
    • v.54 no.1
    • /
    • pp.49-60
    • /
    • 2021
  • This study presents a methodology to estimate two distinct fractal dimensions of natural river basin by using fractal tree concept. To this end, an analysis is performed on fractal features of a complete drainage network which consists of all possible drainage paths within a river basin based on the growth process of fractal tree. The growth process of fractal tree would occur only within the limited drainage paths possessing stream flow features in a river basin. In the case of small river basin, the bifurcation process of network is more sensitive to the growth step of fractal tree than the meandering process of stream segment, so that various bifurcation structures could be generated in a single network. Therefore, fractal dimension of network structure for small river basin should be estimated in the form of a range not a single figure. Furthermore, the network structures with fractal tree from this study might be more useful information than stream networks from a topographic or digital map for analysis of drainage structure on small river basin.

Development of a 3D Modeling System using a variety of images based on Ubiquitous Environment (유비쿼터스 기반의 다양한 영상을 활용한 3D Modeling System의 구축)

  • Kim, Woo-Sun;Heo, Joon;Shim, Jae-Hyun;Choi, Woo-Jung
    • 한국방재학회:학술대회논문집
    • /
    • 2007.02a
    • /
    • pp.418-421
    • /
    • 2007
  • It is important to maintain information by application or 3D modeling through the satellite and UAV image which is a real world. The prevention business has recognized the need for accurate 3-D geospatial information around the disaster region to identify objects to 3D modeling. In this paper, we presented an approach to create 3D model and loading, processing the image using GIS techniques, and the digital topographic maps were used for the DEM and the features of the area. The result is a implementation of the simple application that illustrates the objects in 3-D. The presented approach will be used for identifying objects and assisting in regional planning around the airfields.

  • PDF

A Novel Feature Map Generation and Integration Method for Attention Based Visual Information Processing System using Disparity of a Stereo Pair of Images (주의 기반 시각정보처리체계 시스템 구현을 위한 스테레오 영상의 변위도를 이용한 새로운 특징맵 구성 및 통합 방법)

  • Park, Min-Chul;Cheoi, Kyung-Joo
    • The KIPS Transactions:PartB
    • /
    • v.17B no.1
    • /
    • pp.55-62
    • /
    • 2010
  • Human visual attention system has a remarkable ability to interpret complex scenes with the ease and simplicity by selecting or focusing on a small region of visual field without scanning the whole images. In this paper, a novel feature map generation and integration method for attention based visual information processing system is proposed. The depth information obtained from a stereo pair of images is exploited as one of spatial visual features to form a set of topographic feature maps in our approach. Comparative experiments show that correct detection rate of visual attention regions improves by utilizing depth feature compared to the case of not using depth feature.

Future Extreme Temperature and Precipitation Mechanisms over the Korean Peninsula Using a Regional Climate Model Simulation

  • Lee, Hyomee;Moon, Byung-Kwon;Wie, Jieun
    • Journal of the Korean earth science society
    • /
    • v.39 no.4
    • /
    • pp.327-341
    • /
    • 2018
  • Extreme temperatures and precipitations are expected to be more frequently occurring due to the ongoing global warming over the Korean Peninsula. However, few studies have analyzed the synoptic weather patterns associated with extreme events in a warming world. Here, the atmospheric patterns related to future extreme events are first analyzed using the HadGEM3-RA regional climate model. Simulations showed that the variability of temperature and precipitation will increase in the future (2051-2100) compared to the present (1981-2005), accompanying the more frequent occurrence of extreme events. Warm advection from East China and lower latitudes, a stagnant anticyclone, and local foehn wind are responsible for the extreme temperature (daily T>$38^{\circ}C$) episodes in Korea. The extreme precipitation cases (>$500mm\;day^{-1}$) were mainly caused by mid-latitude cyclones approaching the Korean Peninsula, along with the enhanced Changma front by supplying water vapor into the East China Sea. These future synoptic-scale features are similar to those of present extreme events. Therefore, our results suggest that, in order to accurately understand future extreme events, we should consider not only the effects of anthropogenic greenhouse gases or aerosol increases, but also small-scale topographic conditions and the internal variations of climate systems.

Surface Wind Regionalization Based on Similarity of Time-series Wind Vectors

  • Kim, Jinsol;Kim, Hyun-Goo;Park, Hyeong-Dong
    • Asian Journal of Atmospheric Environment
    • /
    • v.10 no.2
    • /
    • pp.80-89
    • /
    • 2016
  • In the complex terrain where local wind systems are formed, accurate understanding of regional wind variability is required for wind resource assessment. In this paper, cluster analysis based on the similarity of time-series wind vector was applied to classify wind regions with similar wind characteristics and the meteorological validity of regionalization method was evaluated. Wind regions in Jeju Island and Busan were classified using the wind resource map of Korea created by a mesoscale numerical weather prediction modeling. The evaluation was performed by comparing wind speed, wind direction, and wind variability of each wind region. Wind characteristics, such as mean wind speed and prevailing wind direction, in the same wind region were similar and wind characteristics in different wind regions were meteor-statistically distinct. It was able to identify a singular wind region at the top area of Mt. Halla using the inconsistency of wind direction variability. Furthermore, it was found that the regionalization results correspond with the topographic features of Jeju Island and Busan, showing the validity.

Suitability of the PKNU 2 System for Generating the Orthophoto Map

  • Lee, Eun-Khung;Lee, Chang-Hun;Choi, Chul-Uong;Kim, Young-Seup
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.100-102
    • /
    • 2003
  • This system is capable of obtaining quantitative information from images using natural features on the ortho-image maps that correspond with those from topographical maps. However, the qualitative information can also be obtained because because of the excellent visibility of ortho-image maps. There are plenty of promise for the use of ortho-image maps in the next generation topographic technology because of its wider applicability within the field. In keeping with the cutting edge, we produced ortho-image maps by scanning a specified area in narrow sections using the PKNU 2: a multispectral digital aerial photographing system made by ourselves. We evaluated the precision of the ortho-image maps, and performed an evaluation of the PKNU 2 system's capacity to improve the equipment of the PKNU 2. Ortho-image maps were made using Ground Control Points (GCPs) which were obtained from digital maps and aerial photographs of the PKNU 2. Thus, we demonstrated that it was possible to produce the ortho-image maps, which has a good constant level rate of less than 1m. The PKNU 2 system needs to be improving in the sensitivity of level maintenance equipment in the evaluation in terms of performance. It is thus required to survey the GCPs precisely for an accurate study.

  • PDF

Analysis of Field Infrastructure Improvement Types according to Geographic Characteristics and Spatial Distribution of Upland - Comparison of Muan-gun and Hwasun-gun - (지형 특성과 경작지 분포를 고려한 밭정비 유형 분석 - 무안군과 화순군 비교 -)

  • Lee, Jimin;Yoo, Seung-Hwan;Oh, Yun-Gyeong;Kim, Ara
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.60 no.6
    • /
    • pp.133-144
    • /
    • 2018
  • To suggest the field maintenance plan considering the geographical characteristics of the region, we selected representative regions(plain regione and mountain region) and compared spatial distribution of cultivated land in Muan-gun and Hwasun-gun. Firstly, we examined the distribution characteristics of cultivated land according to the scope of the maintenance object with Fragstats. As a result of that, it was found that the cultivated area except rice paddy had the highest aggregation effect. And then, we developed type classification of maintenance considering geographic characteristics and cultivated crops information. As a result of classification, plain land type Muan region was mostly cultivated land suitable for integrated maintenance. On the other hand, Hwasun, a mountainous terrain, needs small-scale maintenance and road maintenance. Based on these results, it was found that more detailed planning is needed for the upland field infrastructure improvement considering the topographic characteristics.