• Journal of Environmental Science International
• /
• v.20 no.9
• /
• pp.1205-1212
• /
• 2011

As serving people's activities, pedestrian road systems are basic and necessary facilities in urban structure. To provide and utilize these pedestrian road systems in residential area would enhance urban environment as well as quality of life. For this reason, pedestrian road should be planned by consideration of people's activity in residential area. Evaluation of existing pedestrian road should be also oriented how people use it and what people do in it. This study amis to investigate functions of pedestrian road system throughout evaluation of user's satisfaction in order to improve better pedestrian road system in residential area. The purposes of this study are to analyze components of factors affecting on user's satisfaction, and to find the relationship among affecting factors. For this study, the on-site questionnaire method was applied to 267 individuals who were collected as the study areas where locate Toyogaoka and Kaidori, Japan. The collected data were clarified exploratory factors, and analyzed relationship between the factors and satisfaction by applying quantitative statistical techniques for the mapping investigation, Mann-Whitney u-test, and correlation. The results of this study are follows. The pedestrian road system is more preferred than surroundings of vehicle roads in residential district area where maintains pedestrian road as open space. In addition, satisfactions of the pedestrian road for each purpose were highly evaluated, because of conformability and convenience for usage. Consequently, the pedestrian road which is secure and greening as an open space is well carried out for the living circulation of residents. It would suggest that pedestrian road have to be managed and planned not a function of circulation but an open space system.

• International Journal of Aeronautical and Space Sciences
• /
• v.14 no.2
• /
• pp.193-199
• /
• 2013

This work investigates the orbital perturbations of the cubesats that lie on LEO due to Earth albedo. The motivation for this paper originated in the investigation of the orbital perturbations for closed- Earth pico-satellites due to the sunlight reflected by the Earth (the albedo). Having assumed that the Sun lies on the equator, the albedo irradiance is calculated using a numerical model in which irradiance depends on the geographical latitude, longitude and altitude of the satellite. However, in the present work the longitude dependency is disregarded. Albedo force and acceleration components are formulated using a detailed model in a geocentric equatorial system in which the Earth is an oblate spheroid. Lagrange planetary equations in its Gaussian form are used to analyze the orbital changes when $e{\neq}0$ and $i{\neq}0$. Based on the Earth's reflectivity data measured by NASA Total Ozone Mapping Spectrometer (TOMS project), the orbital perturbations are calculated for some cubesats. The outcome of the numerical test shows that the albedo force has a significant contribution on the orbital perturbations of the pico-satellite which can affect the satellite life time.

• International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
• /
• v.6 no.1
• /
• pp.22-29
• /
• 2003

This research aims at investigation of accuracy potential of RTK(Real-Time Kinematic) GPS in combination with Echo Sounder(E/S) for the coastal mapping. Apart from this purpose, the accuracy of ambiguity resolution with the OTF(On The Fly) method was tested with respect to the initialization time. The result shows that the accuracy is better than 1cm with 5-minute initialization in the distance of 10km baseline. The seaside topography was measured by the RTK GPS only, on the other hand the seafloor topography was surveyed in combination of RTK GPS and E/S. Comparing to the volume of seaside measured by RTK GPS and digital topographical map, the difference of only 2% was achieved. This indicates that the coastal mapping. As a result, it has been revealed that every possible noise in surveying could be corrected and the accuracy could be improved. The accuracy of GPS data acquired in real time was as good as that acquired by post processing. It is expected that it will be useful for the analysis of coastal geographic characteristics because DTM(Digital Terrain Model) can be also constructed for the harbor reclamation, the dredging, and the variation of soil movement in a river.

• Journal of Ocean Engineering and Technology
• /
• v.17 no.3 s.52
• /
• pp.13-20
• /
• 2003

This research aims at investigation of accuracy potential of RTK(Real-Time Kinematic) GPS in combination with Echo Sounder(E/S) for the coastal mapping. Apart from this purpose, the accuracy of ambiguity resolution with the OTF(On The Fly) method was tested with respect to the initialization time. The result shows that the accuracy is better than 1cm with 5-minute initialization in the distance of 10km baseline. The seaside topography was measured by the RTK GPS only, on the other hand the seafloor topography was surveyed in combination of RTK GPS and E/S. Comparing to the volume of seaside measured by RTK GPS and digital topographical map, the difference of only $2\%$ was achieved. This indicates that the coastal mapping. As a result, it has been revealed that every possible noise in surveying could be corrected and the accuracy could be improved. The accuracy of GPS data acquired in real time was as good as that acquired by post processing. It is expected that it will be useful for the analysis of coastal geographic characteristics because DTM(Digital Terrain Model) can be also constructed for the harbor reclamation, the dredging, and the variation of soil movement in a river.

• Journal of Sensor Science and Technology
• /
• v.25 no.1
• /
• pp.13-19
• /
• 2016

Nowadays, most major automobile manufacturers are very interested, and actively involved, in developing driver alcohol detection system for safety (DADSS) that serves to prevent driving under the influence. DADSS measures the blood alcohol concentration (BAC) from the driver's breath and limits the ignition of the engine of the vehicle if the BAC exceeds the reference value. In this study, to optimize the sensor array of the DADSS, we selected sensors by using three different methods, configured the sensor arrays, and then compared their performance. The Wilks' lambda, stepwise elimination and filter method (using a principal component) were used as the sensor selection methods [2,3]. We compared the performance of the arrays, by using the selectivity and sensitivity as criteria, and Sammon mapping for the analysis of the cluster type of each gas. The sensor array configured by using the stepwise elimination method exhibited the highest sensitivity and selectivity and yielded the best visual result after Sammon mapping.

• The Bulletin of The Korean Astronomical Society
• /
• v.44 no.1
• /
• pp.82.1-82.1
• /
• 2019

Recent analyses of spectro-images of Saturn observed by Visual and Infrared Mapping Spectrometer (VIMS)/Cassini revealed altitudinal distributions of the spectral structure of haze in Saturn's south-polar regions (Kim et al., 2018) and at $55^{\circ}N$ latitude (Kim et al., 2012). However, other regions of Saturn still have not been investigated. We derived series of high-spatial resolution VIMS images of Saturn's limb at various latitudes. Using our developed code, the altitudinal intensity profiles of $3.3-{\mu}m$ emission and H3+ through different latitudes were plotted. Then we obtained the averaged vertical spectra of $3.3-{\mu}m$ emission which is all blended with fluorescent methane and hydrocarbon haze. The vertically-resolved spectra were measured from the limb of Saturn in 50km intervals to see altitudinal variance. We will present a comparison of spectral structures of $3.3-{\mu}m$ emission with different latitudes. Further investigation using radiative transfer to extract adjacent fluorescent CH4, C2H6, and H3+ is needed to derive spectral structure of pure haze. We look forward to a better understanding of aging process in a global view.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.23 no.3
• /
• pp.313-322
• /
• 2005

Rapid advances in technology and changes in human and cultural activities bring about changes to the earth surface in terms of spatial extension as well as time frame of the changes. Such advances introduce shorter updating frequency of maps and geospatial database. To satisfy these requirements, recent research efforts in the geoinformatics field have been focused on the automation and speeding up of the mapping processes which resulted in products such as the digital photogrammetric workstation, GPSIINS, applications of satellite imagery, automatic feature extraction and the LiDAR system. The possibility of automatically extracting buildings and generating contours from airborne LiDAR data has received much attention because LiDAR data produce promising results. However, compared with the manually derived building footprints using traditional photogrammetric process, more investigation and analysis need to be carried out in terms of accuracy and efficiency. On the other hand, generation of the contours with LiDAR data is more efficient and economical in terms of the quality and accuracy. In this study, the effects of various conditions of the pre-processing phase and the subsequent building extraction and contour generation phases for digital mapping have on the accuracy were investigated.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.10
• /
• pp.7182-7188
• /
• 2015

Recently, to improve manual mapping method, digital mapping using high-resolution camera and laser scanner has increasingly attracted attention and the relevant study is reportedly on the rise. In this study, laboratory and field test which are intended to quantitatively analyze and estimate the weathering degree which is one of the engineering characteristics of tunnel face using laser scanner that integrates high-solution imaging technique have been conducted. In a bid to analyze correlation between reflectance of laser scanner and weathering degree, investigation of the factors influencing on reflectance was carried out. And to minimize the effect on RGB value which is one the critical influential factors on reflectance, modification equation obtained from lab test was proposed. Modification equation proposed in this study was verified by comparing the values before and after correction using the data obtained by scanning. Consequently, weathering index estimated by modified reflectance appeared very similar with dominant weathering degree and weathering ratio monitored at the field.

• Journal of Korean Society for Geospatial Information Science
• /
• v.19 no.3
• /
• pp.91-98
• /
• 2011

Road signs are part of the traffic facilities intended to guide drivers to their destinations in a safe and comfortable manner. Due to the creation of new routes, changes to the old routes, and the deterioration of road signs, road signs do require efforts to do ongoing field investigations and put the results in a database. The purpose of this study was to propose methodologies to do field investigations and build a database for road signs efficiently. For that purpose, a mobile mapping system was designed for field investigations. The designed mobile mapping system was comprised of three cameras to produce image information about road signs, GPS/IMU/DMI to obtain information about the position and attitude of a vehicle, and a laser scanner to generate information about the locations of road signs and routes. Also proposed in the study was a procedure to automatically detect the areas of road signs in the road signs images and recognize their characters.

• Korean Journal of Remote Sensing
• /
• v.20 no.6
• /
• pp.369-382
• /
• 2004

The purpose of this study is the investigation of applicability of LSMA(Linear Spectral Mixture Analysis) on the geological uses with different radiometric and spatial types of sensor images such as Terra ASTER and LANDSAT 7 ETM+. As for the actual application case, geologic mapping for mineral exploration using ASTER and ETM+ at the Mongolian plateau region was carried out. After the pre-processing such as the geometric corrections and calibration of radiance, 7 endmembers, as spectral classes for geologic rock types, related to spectral signature deviation for the given application was determined by the pre-surveyed geological mapping information and the correlation matrix analysis, and total 20 images of ASTER and ETM+ were used to LSMA processing. As the results, fraction maps showing individual mineral types in the study area are presented. It concluded that this approach based on LSMA using ETM+ and ASTER is regarded as one of the effective schemes for geologic remote sensing.