Earticle

본 연구는 선형 단순화(line simplification) 방법을 이용하여 수행된 지도 일반화(map generalization) 결과를 실증적으로 비교×검토하는 목적으로 수행되었다. 즉, 더글라스-패커(Douglas-Peucker) 알고리즘을 실제 사례연구에 적용하여, 상이한 허용오차(tolerance) 적용에 따른 결과를 라인의 총 길이와 선분의 수를 중심으로 비교하였다. 미국 뉴욕주 서부 지역을 사례지역으로 선정하여, USGS에서 제공되는 1:24,000 축척의 DLG 포맷의 수문 선형 지도 데이터가 사용되었다. 분석 결과, 허용오차가 커짐에 따라총 길이가 완만하게 줄어드는 반면, 구성 선분의 수는 급격하게 줄어들었다. 또한 이들 간의 강한 양(+)의 상관관계가 탐색되었다.

This research was implemented in order to compare the results of the map generalization quantitatively using the line simplification. That is, the Douglas-Peucker algorithm was applied to the empirical case study, and the results with different tolerances were compared mainly by focusing on the total line length and the number of constituent line segments. The study region was the western part of the New York State, and the DLG-formatted map data at 1:24,000 scale from USGS were used. As a result of the analysis, with the increased tolerances, the total line length in the resulting maps became smaller smoothly, while the number of the line segments drastically. In addition, there was the strong positive relation between them were detected.

In the mobile environments for the vector map services, a map simplification work through the map generalization steps helps improve the readability of the map on a large scale. The generalization operations are various such as selection, aggregation, simplification, displacement, and so on, the formal operation algorithms have not been built yet. Because the algorithms require deep special knowledge and heuristic, which make it hard to automate the processes. This thesis proposes some map generalization algorithms specialized in mobile vector map services, based on previous works. This thesis will show the detail to adapt the approaches on the mobile environment, to display complex spatial objects efficiently on the mobile devices which have restriction on the resources.

Recently researches have been made on the client-side Web GIS, which can lessen the load of a server and provide users with intheractive geographic information. Howwever, the initial delay is the main drawback because of a high volume of geographic data and becausr the server does not associate spatial features with the map scale. Even when a complex spatial object is too small to be distinguished from a point by the naked eyes, it's complete data will be transmitted. This paper proposes a new effcient schema to reduce the response time and increase transmission effciency. Briefly speaking, "Transmit what can be seen" is the main idea. By exploiting the generalization algorithm, the proposed method allows the server to extract readable features from objects according to the display scale. Meanwhile, increasingly detailed map will be cached on the client. Therefore this method will contribute to the transmission efficiency of Web GISs.

This paper introduces the notions of essential and inessential map for countably $textsc{k}$-set contractive maps. These ideas enable us to establish a Krasnoselskii-Petryshyn compression and expansion theorem in a cone for countably $textsc{k}$-set contractive maps.

최근 GIS를 비롯한 각종 지형자료의 응용분야에서 기존의 종이지도가 지니는 제한된 축척 및 정보량 등의 경직성을 탈피한 수치지도의 제작은 시급한 당면 과제로 부각되고 있다. 본 연구에서는 수작업으로 처리되고 있는 편집도의 제작을 자동화하기 위한 방안으로 디지털 환경하에서의 일반화 기법에 대한 연구를 수행하였으며, 주된 연구대상으로는 일반화 알고리즘을 처리 형태별로 개발하여 프로그램화하고 이들 결과를 이용하여 컴퓨터 상에서 특정 지형지물에 대한 소축척지도의 자동제작을 구현하였다. 또한 GIS측면에서의 벡터 데이터로서 동일한 위상구조를 지니기 위한 일반화 전후의 데이터 분석을 토대로 처리형태별 우선 순위의 결정 및 오차량 산정을 실시하여 우리실정에 맞는 일반화의 데이터모델을 분석하였다.

Non-scale digital map have important role in the field of GIS and other application area which using geographical data in recently against conventional map restricted by scale and information. The main objective of this study is to develope the automated map production system for small scale map in conjuction with generalization techniques in a digital environment. We will intend to develope algorithms and programs for each generalization operators based on specific terrain feature with vector data. This study will be performed aspects related to an data model development of generalization process, focussing on priority for processing sequency with maintaining vector topology, and error analysis for generalized digital data.

모바일 환경에서 벡터 지도 서비스를 위해서는 지도 일반화(map generalization) 과정을 통한 지도 간소화 작업이 지도 인지도를 높이는데 큰 도움이 된다. 일반화 연산은 selection, aggregation, simplification, displacement 등 다양하지만 아직 정형화된 연산 알고리즘이 확립되지 못하고 있다. 그 이유는 지도 일반화 알고리즘을 위해서는 자동화되기 어려운 상당한 전문적 지식과 판단이 필요하기 때문이다. 본 논문은 기존의 시도된 일반화 연산 알고리즘들에 기초하여 모바일 환경에 적합한 알고리즘을 고찰하고 제시한다. 복잡한 공간 객체를 제한된 자원의 모바일 기기에 효율적으로 출력하기 위한 다양한 접근 방법을 모바일 환경에 적용하는 과정을 보인다.

In the mobile environments for the vector map services, a map simplification work through the map generalization steps helps improve the readability of the map on a large scale. The generalization operations are various such as selection, aggregation, simplification, displacement, and so on, the formal operation algorithms have not been built yet. Because the algorithms require deep special knowledge and heuristic, which make it hard to automate the processes. This thesis proposes some map generalization algorithms specialized in mobile vector map services, based on previous works. We will show the detail to adapt the approaches on the mobile environment, to display complex spatial objects efficiently on the mobile devices which have restriction on the resources

디지탈 지도 데이타베이스는 다중 축적의 개념을 포함하여 여러 가지 목적을 두고 제작되며 단일 축적으로만 사용하기 위해 Base Map을 구축하는 사례는 극히 보기 드믄 현상이라고 할 수 있다. 따라서 지도의 일반화와 다중표현에 대한 Line의 단순화 처리에 있어서 가장 중요한 문제는 일반화된 그래픽 데이타의 정확도와 인식도를 모두 부여하기 위해 Base Map 상의 정보를 단순화하기 위해 설정하는 허용범위를 디지틸 화일내에서 Feature의 형태에 따라 수정이 가능하도록 하는 것이다. 본 연구에서는 하나의 디지털 화일내에서 다양한 축척상으로 수행되는 Line의 단순화에 대한 여러가지 알고리즘을 고찰하였으며, 지도의 표현상에 변화를 줄 수 있는 선형성 Feature 별로 축척에 따른 규칙을 설정하였다. 수치화된 line 데이타 사이의 상관성을 분석하기 위하여 2가지 변형량을 측정하여 5가지 알고리즘에 대한 평가를 시도하였다. 데이타의 분석결과 Douglas-Peucker 알고리즘이 단순화 후의 변형량에 있어 가장 작은 영향을 받음을 알 수 있었다. 이러한 연구 결과로부터 디지탈 화일을 소축척으로 표현하기 위해 단순화를 실시할 경우 내부적으로 지니고 있어야 하는 기하학적인 항목으로서 그 크기와 변동량에 대한 수치적인 안을 제시함에 따라 지도의 단순화에 대한 가능성을 입증하였다.

The digital map database is often produced for multiple purposes, including mapping at multiple scales; it is increasingly rare that a base map is digitized for mapping at a single scale. The most important problems in process of line simplification in map generalization and multiple representation is that tolerance value selected for simplifying base map information must be modified as feature geometry varies within the digital file to ensure both accuracy and recognizability of graphic details on a generalized map. In this study, we explored various algorithms regarding to line simplication at many scales from a single digital file, and presents a rule by which to determine those scale at which line feature geometry might be expected to change in map representation. By applying two measured of displacement between a digitized line and its simplification, five algorithms have been evaluated. The results indicate that, of the five, the Douglas-Peucker routine produced less displacement between a line and its simplification. The research has proved to automating map simplification, incorporating numeric guidelines into digital environment about what magnitude and variation in geometric detail should be preserved as the digital data is simplified for representation at reduced map scales.

Recently, various geographic information systems have been used based on spatial information of geographic information systems. Accordingly, it is essential to produce a large-scale map as a small-scale map for various uses of spatial information. However, maps currently being produced have inconsistencies between data due to production timing and limitations in expression, and productivity efficiency is greatly reduced due to errors in products or overlapping processes. In order to improve this, various efforts are being made, such as publishing research and reports for automating domestic mapping, but because there is no specific result, it relies on editors to make maps. This is mainly done by hand, so the time required for mapping is excessive, and quality control for each producer is different. In order to solve these problems, technology that can be automatically produced through computer programs is needed. Research has been conducted to apply the rule base to geometric generalization. The algorithm tolerance setting applied to rule-based modeling is a factor that greatly affects the result, and the level of the result changes accordingly. In this paper, we tried to study the effectiveness of mapping according to tolerance setting. To this end, the utility was verified by comparing it with a manually produced map. In addition, the original data and reduction rate were analyzed by applying generalization algorithms and tolerance values. Although there are some differences by region, it was confirmed that the complexity decreased on average. Through this, it is expected to contribute to the use of spatial information-based services by improving tolerances suitable for small-scale mapping regulations in order to secure spatial information data that guarantees consistency and accuracy.

The digital map version 2.0 is national base map which is used for frame work data, paper map making as well as geographic information system. National Geographic Institude has been research to make small scale digital map by using large scale digital map. NGI made from 25 1/5,000 digital maps to one 1/25,000 digital map ver 2.0 with map generalization system in 2003. However, they could not make 1/10,000 and l/50,000 digital map version 2.0 because of There is no portrayal on the scale 1/10,000 and 1/50,000 digital map in the existing regulations. therefore. We create the specification of the digital map on scale in order to make small scale digital map version 2.0 such as 1/10,000 and 1/50,000 scale.

본 연구는 자전거 이용 활성화를 위한 자전거도로지도 제작에 관한 연구로써, 먼저 현재 제작되어 사용되고 있는 자전거도로지도의 내용과 체제를 분석하고, 이에 대한 문제점을 제시한 후, 지도학적 관점에서 새로운 자전거도로지도 제작에 관한 방향과 방법을 제시하고자 한다. 연구의 결과 현재 제작되어 사용되고 있는 자전거도로지도에는 다음과 같은 3가지의 문제점이 도출되었다. 첫째 전국적으로 연속된 자전거도로정보를 제공하지 못함으로 자전거를 이용한 광역적 이동에 부적절하다. 둘째 자전거 관련 지리적 현상의 지도학적 일반화가 현행법제도를 충분히 반영하고 있지 못하다. 셋째 자전거도로지도 요소의 구도와 배치가 지도학적 체계를 준수하지 못하고 있다. 이상의 문제를 해결하여 과학적이고 정확한 자전거도로지도를 제작하기 위한 방안으로 다음의 방법을 제안한다. 먼저 우리나라의 전국도로망도에 하나의 사상으로 표시된 국도를 자전거 이용활성화 관련법에서 규정하고 있는 3가지의 자전거도로 유형으로 구분·표시하도록 전국도로망도를 수정하고, 이를 바탕으로 대축척의 지역별, 태마별 자전거도로지도를 제작하는 방법이다.

This research deals with the road map making for bicycle to revitalize the good use of bicycle. First, the contents and systems of the current road map for bicycle are analyzed, and its problems are pointed out followed by the suggestion of the new direction and methodology of the road map making for bicycle from cartographic point of view. Research on the analysis of the current road map for bicycle revealed that there are three major problems. First, nationwide movement using bicycle is inappropriate since the nationwide road map for bicycle is not provided currently. Second, the existing regulation system does not sufficiently reflect the cartographic generalization related to the feature of bicycle. Third, arrangement and system for the element of map for bicycle does not follow the cartographic system. This research suggest the following methodologies in order to resolve the above problems and to make the rational and accurate road map for bicycle. First of all, three types of bicycle road map should be indicated at the local road map in which only one feature is appeared in national road map. Based on the that map, large scale regional and theme road map for bicycle could be made. Research on the analysis of the current road map for bicycle revealed that there are three major problems. First, nationwide movement using bicycle is inappropriate since the nationwide road map for bicycle is not provided currently. Second, the existing regulation system does not sufficiently reflect the cartographic generalization related to the geographic feature. Third, arrangement and system for the element of map for bicycle does not follow the atlas system. This research suggest the following methodologies in order to resolve the above problems and to make the rational and accurate road map for bicycle. First of all, three types of bicycle road map should be indicated at the local road map in which only one feature is appeared in national road map. Based on the that map, large scale regional and theme road map for bicycle could be made.