• Korean Journal of Remote Sensing
• /
• v.39 no.5_4
• /
• pp.1165-1172
• /
• 2023

Recently, Korea has declared carbon neutrality by 2050. The Korea Forest Service is promoting the precision and high technology of forest resource surveys. As such, the demand for forest resource management is increasing, and the need to build a digital twin of forest space is increasing. However, to date, digital twin has only built and provided virtual city services, which are city and nationwide digital twin environments. Three-dimensional digital twin services targeting forest space are not operated and provided. Therefore, in this study, we aimed to implement a forest digital twin environment to provide 3D forest spatial information services corresponding to vertical information such as tree-level height and thorax diameter. By lightweighting realistic 3D tree models and applying 3D Tiles, we confirmed the feasibility of implementing a forest digital twin environment for 3D forest spatial information services. Through continuous research, we plan to implement a forest digital twin that can deploy and service 3D tree models for trees nationwide, including street trees in urban areas. This is expected to enable the development of forest digital twin services for forest resource management.

• Korean Journal of Heritage: History & Science
• /
• v.56 no.3
• /
• pp.46-59
• /
• 2023

Various Baekje ground-level building sites have been identified, in Pungnaptoseong Fortress, including Mirae Village's site E-1. However, building site E-1 is the only one with excavated roof tiles that are directly connected to the building site. As for building sites E-2, D-1, and D-2, which are comparable to site E-1, it is very possible that they had tiles on the roof based on their jeoksim (blocking facilities for roof slopes) and building structures. Also, although they are semi-underground pit structures, pit building sites A-30 and modern apartment site A-5, as well as the No.44 remains of Gyeongdang District, which is closer to a ground-level type, the buildings with tiles may have been constructed in the form of partial tile roofs rather than full-face tile roofs. Therefore, there may be several reasons behind the use of tiles on roofs in the early days, but the primary background of the building's authoritative function would have been considered first. Considering that China and Japan started using tiles on nationally important buildings such as palaces, temples, and ritual buildings, it may be presumed that Baekje began using tiles from the time it centralized power. It is believed that Baekje's early roof tile buildings evolved from rudimentary residential architecture to advanced public architecture, taking into consideration fire prevention and structural stability in large buildings. It is difficult to find similar cases in Korea with structural features such as the elevated foundations or underground stone foundations that can be found in Mirae Village building site E-1. Rather, similar architectural techniques can be found in China and Japan. In China, similar construction techniques were discovered in buildings of worship that were primarily built in the palace surroundings, such as Jangan Castle. Based on this, it appears that roof tile building sites, such as site E-1, that have been discovered have a strong correlation with the characteristics of buildings of worship, and ground type buildings, such as sites D-1 and D-2, are important facilities that are related to important public facilities such as state-run warehouses. This provides many implications regarding the early Baekje city structure.

• Journal of KIISE:Computer Systems and Theory
• /
• v.32 no.8
• /
• pp.418-425
• /
• 2005

3D surface reconstruction is to make the original geometry of 3D objects from 2D geometric information. Barequet's algorithm is well known and most widely used in surface reconstruction. It tiles matched regions first, then triangulates clefts using dynamic programming. However it takes considerably long processing time while manipulating complex model. Our method tiles a simple region that does not have branches along minimally distant vertex pairs at once. When there are branches, our method divides contour lines into a simple region and clefts. We propose a fast and simple method that calculates medial axes using a minimum distance in cleft region. Experimental results show that our method can produce accurate models than the previous method within short time.

• Proceedings of the KSRS Conference
• /
• 2007.10a
• /
• pp.85-89
• /
• 2007

This paper presents the method to provide a fast service for user in image manipulation such as zooming and panning of huge size high resolution satellite image (e.g. Giga bytes per scene). The proposed technique is based on the hierarchical structure that has 3D-Tiling in horizontal and vertical direction to provide the image service more effectively than 2D-Tiling technique in the past does. The essence of the proposed technique is to create tiles that have optimum level of horizontal as well as vertical direction on the basis of current displaying area which changes as user manipulates huge image. So this technique provides seamless service, and will be very powerful and useful for manipulation of images of huge size without data conversion.

• Korean Journal of Remote Sensing
• /
• v.23 no.5
• /
• pp.375-383
• /
• 2007

This paper presents the method to provide a fast service for user in image manipulation such as zooming and panning of huge size high resolution satellite image(e.g. Giga bytes per scene). The proposed technique is based on the hierarchical structure that has 3D-Tiling in horizontal and vertical direction to provide the image service more effectively than 2D-Tiling technique in the past does. The essence of the proposed technique is to create tiles of optimum level in real time on the basis of current displaying area, which change as user manipulates huge image. Consequently, this technique provides seamless service, and will be very powerful and useful for manipulation of images of huge size without data conversion.

• Resources Recycling
• /
• v.4 no.4
• /
• pp.37-58
• /
• 1995

Whole tues were put uto cement kiln inlet where the tempmalures or gas and cemcnt-raw-materials were 1050 and 800- 850.C. respcclrvely. Tl~ck iln consisls of \ulcorner-stage suspension preheatel- and air quenching coolers The amount of wusle tlrcs added in lhc normal encrgy in lhc ce~ncnlk iln was 3, 5, 7% by volume Welght and steel contents of tiles. ulti~~iaalcn d elemental analysis, ash contents. ash hsion temperature. etc, wete detcnutned to inveshgate thc prnpcrlics a1 tires and ilreir ashes. Flucluat~ons of cement kiln placess, cement quality and an pollulton were invesligalerl during lhc burning tins. When the Ieeding ralio ol wasle lires to normal cncrgy was 50'0, there was nn wlde d~ffereilces m the cemmt quctlity and air pollutcon between operation with tiles and withoul tires. Tl~ch cal iccovcry was uhout 50% w~th5 % add~tionI n the nonndl energy. There was a little lxt fluctuation of cement quultty ncld an pollution at olher feeding ralios.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.10a
• /
• pp.309-311
• /
• 2014

The tile-based rendering technique which divides the screen area into tiles of a specific size and creates a 3D graphic model of one tile at a time is used to efficiently utilize limited resources in a 3D graphic pipeline. In this paper, the tiling speed of tile-based rendering was improved by reducing the count of calling lower-levels in the hierarchical tile-based rendering technique. The tiling speed of the proposed Rasterizer is 13.030ms which is 56% faster than 29.614ms of multi-sort tiling and 24% faster than 17.208ms of the conventional hierarchical tiling technique.

• Geophysics and Geophysical Exploration
• /
• v.12 no.1
• /
• pp.69-76
• /
• 2009

We report an implementation of the Ground Penetrating Radar (GPR) survey at a site that corresponds to a ruined castle. The objective of the survey was to characterise buried archaeological structures such as walls and tiles in Van Khan Tooril's Ruin, Mongolia, by 2D and 3D GPR techniques. GPR datasets were acquired in an area 10mby 9 m, with 10 cm line spacing. Two datasets were collected, using GPR with 500MHz and 800MHz frequency antennas. In this paper, we report the use of instantaneous parameters to detect archaeological targets such as tile, brick, and masonry by polarimetric GPR. Radar polarimetry is an advanced technology for extraction of target scattering characteristics. It gives us much more information about the size, shape, orientation, and surface condition of radar targets. We focused our interpretation on the strongest reflections. The image is enhanced by the use of instantaneous parameters. Judging by the shape and the width of the reflections, it is clear that moderate to high intensity response in instantaneous amplitude corresponds to brick and tiles. The instantaneous phase map gave information about the location of the targets, which appeared as discontinuities in the signal. In order to increase our ability to interpret these archaeological targets, we compared the GPR datasets acquired in two orthogonal survey directions. A good correlation is observed for the alignments of reflections when we compare the two datasets. However, more reflections appear in the north-south survey direction than in the west-east direction. This is due to the electric field orientation, which is in the horizontal plane for north-south survey directions and the horizontally polarised component of the backscattered high energy is recorded.

• Journal of Gifted/Talented Education
• /
• v.22 no.3
• /
• pp.619-637
• /
• 2012

The purpose of this study is to develop a new program for elementary math-gifted students by using 'Girih Tililng' and apply it to the elementary students to improve their math-ability. Girih Tililng is well known for 'the secrets of mathematics hidden in Mosque decoration' with lots of recent attention from the world. The process of this study is as follows; (1) Reference research has been done for various tiling theories and the theories have been utilized for making this study applicable. (2) The characteristic features of Mosque tiles and their basic structures have been analyzed. After logical examination of the patterns, their mathematic attributes have been found out. (3) After development of Girih tiling program, the program has been applied to math-gifted students and the program has been modified and complemented. This program which has been developed for math-gifted students is called 'Exploring the Secrets of Girih Hidden in Mosque Patterns'. The program was based on the Renzulli's three-part in-depth learning. The first part of the in-depth learning activity, as a research stage, is designed to examine Islamic patterns in various ways and get the gifted students to understand and have them motivated to learn the concept of the tiling, understanding the characteristics of Islamic patterns, investigating Islamic design, and experiencing the Girih tiles. The second part of the in-depth learning activity, as a discovery stage, is focused on investigating the mathematical features of the Girih tile, comparing Girih tiled patterns with non-Girih tiled ones, investigating the mathematical characteristics of the five Girih tiles, and filling out the blank of Islamic patterns. The third part of the in-depth learning activity, as an inquiry or a creative stage, is planned to show the students' mathematical creativity by thinking over different types of Girih tiling, making the students' own tile patterns, presenting artifacts and reflecting over production process. This program was applied to 6 students who were enrolled in an unified(math and science) gifted class of D elementary school in Daejeon. After analyzing the results produced by its application, the program was modified and complemented repeatedly. It is expected that this program and its materials used in this study will guide a direction of how to develop methodical materials for math-gifted education in elementary schools. This program is originally developed for gifted education in elementary schools, but for further study, it is hoped that this study and the program will be also utilized in the field of math-gifted or unified gifted education in secondary schools in connection with 'Penrose Tiling' or material of 'quasi-crystal'.

• Korean Journal of Remote Sensing
• /
• v.36 no.5_4
• /
• pp.1195-1207
• /
• 2020

With the development of GeoWeb technology, 2D/3D spatial information services through the web are also has been used increasingly in the application of disaster management. This paper is suggested to construct a web-based 3D geo-spatial information mapping platform to visualize various spatial information collected at the disaster site in a web environment. This paper is presented a web-based geo-spatial information mapping service plan for the various types of 2D/3D spatial data and large-volume LiDAR point cloud data collected at the disaster accident site using HTML5/WebGL, web development standard technology and open source. Firstly, the collected disaster site survey 2D data is constructed as a spatial DB using GeoServer's WMS service and PostGIS provided an open source and rendered in a web environment. Secondly, in order to efficiently render large-capacity 3D point cloud data in a web environment, a Potree algorithm is applied to simplifies point cloud data into 2D tiles using a multi-resolution octree structure. Lastly, OpenLayers3 based 3D web mapping pilot system is developed for web visualization of 2D/3D spatial information by implementing basic and application functions for controlling and measuring 3D maps with Graphic User Interface (GUI). For the further research, it is expected that various 2D survey data and various spatial image information of a disaster site can be used for scientific investigation and analysis of disaster accidents by overlaying and visualizing them on a built web-based 3D geo-spatial information system.