• Journal of KIISE:Computer Systems and Theory
• /
• v.31 no.7
• /
• pp.402-413
• /
• 2004

This paper presents an Implementation of Korean standard 128-bit block cipher SEED for the small (8 or 16-bits) embedded system using a low-cost FPGA(Field Programmable Gate Array) chip. Due to their limited computing and storage capacities most of the 8-bits/16-bits small embedded systems require a separate and dedicated cryptography processor for data encryption and decryption process which require relatively heavy computation job. So, in order to integrate the SEED with other logic circuit block in a single chip we need to invent a design which minimizes the area demand while maintaining the proper performance. But, the straight-forward mapping of the SEED specification into hardware design results in exceedingly large circuit area for a low-cost FPGA capacity. Therefore, in this paper we present a design which maximize the resource sharing and utilizing the modern FPGA features to reduce the area demand resulting in the successful implementation of the SEED plus interface logic with single low-cost FPGA. We achieved 66% area accupation by our SEED design for the XC2S100 (a Spartan-II series FPGA from Xilinx) and data throughput more than 66Mbps. This Performance is sufficient for the small scale embedded system while achieving tight area requirement.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.25 no.12
• /
• pp.1292-1299
• /
• 2014

Weather radar systems can provide weather information of the ground, sea, and air in extensive spatial coverage in near real time. However, it becomes problematic when ground clutter signal exists around precipitation because strong signals of ground can cause a false precipitation report. A large percentage of land coverage of Korea consists of mountainous regions where ground clutter needs to be mitigated for more accurate prediction. Thus, it is considered necessary to introduce a new suitable ground clutter removal technique specifically adequate for Korea. In this paper, the C-Map(Clutter Map) method using raw radar signals is proposed for removing ground clutter using a terrain-adaptive clutter map. A clutter map is generated using raw radar signals(I/Q) of clear days, then it is subtracted from received radar signals in frequency domain. The proposed method is applied to the radar data acquired from Sobaeksan rain radar and the result shows that the clutter rejection ratio is about 91.17 %.

• Korean Journal of Remote Sensing
• /
• v.32 no.2
• /
• pp.141-153
• /
• 2016

Reliable assessment of Land Use and Land Cover (LULC) changes greatly improves many practical issues in hydrography, socio-geographical research such as the observation of erosion and accretion, coastal monitoring, ecological effects evaluation. Remote sensing imageries can offer the outstanding capability to monitor nature and extent of land and associated changes over time. Nowadays accurate analysis using remote sensing imageries with high spatio-temporal resolution is required for environmental monitoring. This study develops a methodology of mapping and change detection in LULC by using classified Korea Multi-Purpose Satellite-2 (KOMPSAT-2) multispectral imageries at Jeonbuk and Jeonnam provinces including protected tidal flats located in the west coasts of Korean peninsula from 2008 to 2015. The LULC maps generated from unsupervised classification were analyzed and evaluated by post-classification change detection methods. The LULC assessment in Jeonbuk and Jeonnam areas had not showed significant changes over time although developed area was gradually increased only by 1.97% and 4.34% at both areas respectively. Overall, the results of this study quantify the land cover change patterns through pixel based analysis which demonstrate the potential of multispectral KOMPSAT-2 images to provide effective and economical LULC maps in the coastal zone over time. This LULC information would be of great interest to the environmental and policy mangers for the better coastal management and political decisions.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.10 no.4
• /
• pp.77-85
• /
• 1990

The application of remote sensing in small scale mapping has recently been widened to various fields such as information analysis of landuse, environmental conservation and natural resources. SPOT imagery, in particular, offers data which can be processed for 3-dimensional point determination. This is made possible by its high resolution, appropriate swatch width/altitude ratio and stereo imaging capabilities. This study aims to develop a suitable polymonial and an algorithm in the determination of exterior orientation which is essential in the 3-dimensional point determination of SPOT imgery. An algorithm is presented in this study to determine the exterior orientation of a preprocessed level lB film of the satellite image. It was found that a polynominal of 15 parameters is the best fit polynominal for exterior orientation determination, where 1st order line function is used for positon ($X_o$, $Y_o$, $Z_o$) and 2nd order line function is used for orientation (${\kappa}_o$, ${\phi}_o$, ${\omega}_o$).

• Journal of the Korean association of regional geographers
• /
• v.18 no.4
• /
• pp.464-472
• /
• 2012

To assess the space-time clustering of FMD(Foot-and-Mouth Disease) epidemic occurred in Korea between November 2010 to April 2011, geographical information system (GIS)-based spatial analysis technique was used. Farm address and geographic data obtained from a commercial portal site were integrated into GIS software, which we used to map out the color-shading geographic features of the outbreaks through a process called thematic mapping, and to produce a visual representation of the relationship between epidemic course and time throughout the country. FMD cases reported in northern area of Gyounggi province were clustered in space and time within small geographic areas due to the environmental characteristics which livestock population density is high enough to ease transmit FMD virus to the neighboring farm, whereas FMD cases were clustered in space but not in time for southern and eastern area of Gyounggi province. When analyzing the data for 7-day interval, the mean radius of the spatial-time clustering was 25km with minimum 5.4km and maximum 74km. In addition, the radius of clustering was relatively small in the early stage of FMD epidemic, but the size was geographically expanded over the epidemic course. Prior to implementing control measures during the outbreak period, assessment of geographic units potentially affected and identification of risky areas which are subsequently be targeted for specific intervention measures is recommended.

• The Journal of Engineering Geology
• /
• v.30 no.3
• /
• pp.289-302
• /
• 2020

To determine the shallow subsurface structure and sliding surface of land creeping in 2016 at Hadong-gun, Gyeongsangnam-do, geophysical surveys (electric resistivity, and refraction seismic methods, borehole televiewer) and slope stability analysis were conducted. The subsurface structure delineated with borehole lithologies and seismic velocity structures provided the information that the sediment layer on the top of the slope was rather as thick as 20 m and the underlying weathered rock (anorthosite) was thinner than 1 m. Based on the tension cracks observed during the geological mapping, televiewer scanning was performed at the borehole BH-2 and detected the intensive fracture zones at the ground-water level, associated with the slip weak zones mapped in dipole-dipole electrical resistivity section. Downslope sliding and slightly upward pushing at the apex of high resistive bedrock explains the curved slip plane of the land creeping. Such a convex structure might play a role of natural toe abutment for preventing the downward development of slip weak zones. In slope stability analysis, the safety factors of the slip weak zone are calculated with varying the groundwater levels for dry and rainy seasons and the downslope is founded to be unstable with safety factor of 0.89 due to fully saturated material in rainy season.

• Journal of Environmental Impact Assessment
• /
• v.27 no.5
• /
• pp.417-430
• /
• 2018

Identification and mangement of ecosystem service hotspots are necessary to set environmental policies that include concepts of ecosystem service. Assessment and mapping of ecosystem service hotspot referring areas with high amount of ecosystem services provide essential information to manage ecosystem services effectively. Assessment of hotspots based on regional environmental stakeholders' perception is an useful approach to identify priority areas where management practices are required. This study estimated weights on regulating ecosystem services from regional environmental stakeholders' surveys in Ansan, and then, identified regulating service hotspots with weights. The result indicated that regulating services are, in order of importance, water quality, air quality, erosion, and climate control. The north-eastern forest of Ansan was mainly revealed as an ecosystem service hotspot. Ecosystem service hotspots were spatially distributed similarly regardless of environmental stakeholders' weights. Identification of ecosystem service hotspot with environmental stakeholders' perception can be applied in decision-support tools for ecosystem service management.

• Clinics in Shoulder and Elbow
• /
• v.15 no.2
• /
• pp.73-78
• /
• 2012

Purpose: Understanding exactly detailed anatomy and morphology of scapula is very important for further surgical procedures. This study was intended to provide accurate anatomic and morphologic information of scapula by exactly measuring scapular thickness using computed tomography and reconstructing its geometric model. Materials and Methods: Eight average lengths and two angles of 102 scapular structures obtained from 51 cadavers were generally measured by computed tomography. Also, to measure the scapular thickness, sagittal planes of each scapula were divided almost equally and the thicknesses of each sagittal plane was measured by computed tomography. After measuring every thickness, average results were calculated and the gender difference was compared by Student t-test. Results: Average results of the thickness of glenoid fossa, lateral border, medial border, and the middle 1/3 portion of the scapular body were 22.4 mm, 13.83 mm, 4.44 mm and 2.06 mm, respectively. Also, male scapulars were found to be significantly thicker than female. Based on these measured thicknesses, we reconstructed the 3-dimensional geometric model of scapula. Conclusion: From these results, glenoid fossa and lateral border were the thickest part of scapula, while the middle 1/3 portion of the scapular was the thinnest.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.7
• /
• pp.218-223
• /
• 2020

This study examined the accessibility of emergency rooms according to the population density and distance in Daegu Metropolitan City to help improve the quality and emergency medical accessibility problems in Daegu Metropolitan City. To observe the geographical requirements, the number of population in eup, myeon, dong, available emergency, and available emergency compared to the population were mapped through the S-GIS of Statistics Korea to visualize the data based on the 3km radius. To determine the difference in accessibility to emergency rooms for each district in Daegu Metropolitan City, the data were analyzed by ANOVA and Scheffe. According to the average number of emergencies available in Daegu Metropolitan City within a 3-kilometer radius were 5.7 in Jung-gu, 5.0 in Nam-gu, 1.6 in Buk-gu, 0.4 in Dong-gu, 2.4 in Seo-gu, 0.9 in Suseong-gu, 3.5 in Dalseo-gu, and 0.1 in Dalseong-gun; there was a statistically significant difference (p<.001). The available emergency within a 3km radius and available emergency per 1,000 people were concentrated in the center. Therefore, it may be necessary to institute an urban emergency medical network by establishing a point that serves as an intermediate hub to provide emergency medical care to citizens far from the center.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.13 no.4
• /
• pp.305-312
• /
• 2010

Seagrass beds are a type of coastal wetland with many ecosystem services and precious economic values. Seagrass meadows used to be widespread along the coasts in northern Chinese seas, yet they have long been overlooked and lack devoted study on their history and status. This paper firstly reveals, by synthesis of information on composition of seagrass species and their distribution, that the seagrasses in this region have experienced considerable declines, both in terms of distribution and biomass, from the earliest record to present days. Then, a case study at the seagrass bed of Chudao is described to show the status of representative seagrass meadows. The results indicate that the environmental condition is good, seagrasses are in recovery, the planktoners are healthy and rich fishery resources and the mammal finless porpoise are associated with the seagrass bed. The cause(s) of historical seagrass decline and current conditions are also discussed, and future recommendations on seagrass protection and mapping are suggested.