• 국제학술발표논문집
• /
• The 9th International Conference on Construction Engineering and Project Management
• /
• pp.1247-1248
• /
• 2022

Due to rapid urbanization and population growth, it has become crucial to analyze the various volumes and characteristics of pedestrian pathways to understand the capacity and level of service (LOS) for pathways to promote a better walking environment. Different indicators have been developed to measure pedestrian volume. The pedestrian level of service (PLOS), tailored to analyze pedestrian pathways based on the concept of the LOS in transportation in the Highway Capacity Manual, has been widely used. PLOS is a measurement concept used to assess the quality of pedestrian facilities, from grade A (best condition) to grade F (worst condition), based on the flow rate, average speed, occupied space, and other parameters. Since the original PLOS approach has been criticized for producing idealistic results, several modified versions of PLOS have also been developed. One of these modified versions is perceived PLOS, which measures the LOS for pathways by considering pedestrians' awareness levels. However, this method relies on survey-based measurements, making it difficult to continuously deploy the technique to all the pathways. To measure PLOS more quantitatively and continuously, researchers have adopted computer vision technologies to automatically assess pedestrian flows and PLOS from CCTV videos. However, there are drawbacks even with this method because CCTVs cannot be installed everywhere, e.g., in alleyways. Recently, a technique to monitor bio-signals, such as electrodermal activity (EDA), through wearable sensors that can measure physiological responses to external stimuli (e.g., when another pedestrian passes), has gained popularity. It has the potential to continuously measure perceived PLOS. In their previous experiment, the authors of this study found that there were many significant EDA responses in crowded places when other pedestrians acting as external stimuli passed by. Therefore, we hypothesized that the EDA responses would be significantly higher in places where relatively more dynamic objects pass, i.e., in crowded areas with low PLOS levels (e.g., level F). To this end, the authors conducted an experiment to confirm the validity of EDA in inferring the perceived PLOS. The EDA of the subjects was measured and analyzed while watching both the real-world and virtually created videos with different pedestrian volumes in a laboratory environment. The results showed the possibility of inferring the amount of pedestrian volume on the pathways by measuring the physiological reactions of pedestrians. Through further validation, the research outcome is expected to be used for EDA-based continuous measurement of perceived PLOS at the alley level, which will facilitate modifying the existing walking environments, e.g., constructing pathways with appropriate effective width based on pedestrian volume. Future research will examine the validity of the integrated use of EDA and acceleration signals to increase the accuracy of inferring the perceived PLOS by capturing both physiological and behavioral reactions when walking in a crowded area.

• 한국실내디자인학회논문집
• /
• 제20권3호
• /
• pp.233-241
• /
• 2011

Modern society is heading towards a knowledge & information based society where knowledge and information is valued, or a knowledge creation society where information is analyzed and processed to be used as knowledge. This means that not only individuals but also every organization is always surrounded by information and that we are witnessing a transition into a society where the value of knowledge and information is increasingly higher so sometimes we must actively explore and use the information across the whole social structure involved with politics, economy and culture. Recently, while the amount of information at public libraries at home and abroad has greatly increased in volume and the kinds have become diverse, efforts for digitalizing and integrating knowledge & information resources are being pursued aggressively. A new paradigm of facilities and space configuration for public libraries is required so that along with traditional library service there will exist integrated links and exchange of digital information resources and all users will be able to equally access that information. Therefore, assuming that human, information and space are important design factors as to space planning for public libraries, this study compared characteristics of the space structure and the form of exchange of knowledge & information through examples involved with public libraries having opened in the past three to four years from perspectives of space sociology and communication. This is a basic study to provide organized design guidelines about the form of exchange of creative knowledge & information from various perspectives in the knowledge & information age. Also this study is considered to have a significance in activating communication with users through exchange, creation and experience of knowledge & information, which is a social role that modern public libraries support.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
• /
• pp.235-240
• /
• 2006

The paper will give an overview of the mission of GalTeC and then concentrate on two main aspects. The first more detailed aspect, is the analysis of the key performance parameters for the Galileo system services and presenting a technical overview of methods and algorithms used. The second more detailed aspect, is the service volume prediction including service dimensioning using the Prediction tool. In order to monitor and validate the Galileo SIS performance for Open Service (OS) and Safety Of Life services (SOL) regarding the key performance parameters, different analyses in the SIS domain and User domain are considered. In the SIS domain, the validation of Signal-in-Space Accuracy SISA and Signal-in-Space Monitoring Accuracy SISMA is performed. For this purpose first of all an independent OD&TS and Integrity determination and processing software is developed to generate the key reference performance parameters named as SISRE (Signal In Space Reference Errors) and related over-bounding statistical information SISRA (Signal In Space Reference Accuracy) based on raw measurements from independent sites (e.g. IGS), Galileo Ground Sensor Stations (GSS) or an own regional monitoring network. Secondly, the differences of orbits and satellite clock corrections between Galileo broadcast ephemeris and the precise reference ephemeris generated by GalTeC will also be compared to check the SIS accuracy. Thirdly, in the user domain, SIS based navigation solution PVT on reference sites using Galileo broadcast ephemeris and the precise ephemeris generated by GalTeC are also used to check key performance parameters. In order to demonstrate the GalTeC performance and the methods mentioned above, the paper presents an initial test result using GPS raw data and GPS broadcast ephemeris. In the tests, some Galileo typical performance parameters are used for GPS system. For example, the maximum URA for one day for one GPS satellite from GPS broadcast ephemeris is used as substitution of SISA to check GPS ephemeris accuracy. Using GalTeC OD&TS and GPS raw data from IGS reference sites, a 10 cm-level of precise orbit determination can be reached. Based on these precise GPS orbits from GalTeC, monitoring and validation of GPS performance can be achieved with a high confidence level. It can be concluded that one of the GalTeC missions is to provide the capability to assess Galileo and general GNSS performance and prediction methods based on a regional and global monitoring networks. Some capability, of which first results are shown in the paper, will be demonstrated further during the planned Galileo IOV phase, the Full Galileo constellation phase and for the different services particularly the Open Services and the Safety Of Life services based on the Galileo Integrity concept.

• Corrosion Science and Technology
• /
• 제4권3호
• /
• pp.100-107
• /
• 2005

Reinforcing steel bars in reinforced concrete structures are protected from corrosion by passive film on the steel surface inside concrete with high alkalinity. However, when the passive film breaks down due to chloride ion ingressed into the RC structures, a corrosion initiates at the surface of steel bars. Then, internal pressure by volume expansion of corrosion products in reinforcing bars induces cracking and spalling of cover concrete, which reduces not only durability performance but also structural performance in RC structures. In this paper, a service life prediction of RC structures is carried out by using a micro-mechanics based corrosion model. The corrosion model is composed of a chloride penetration model to evaluate the initiation of corrosion and an electric corrosion cell model and an oxygen diffusion model to evaluate the rate and the accumulated amounts of corrosion. Then, a corrosion cracking model is combined to the models to evaluate critical amount of corrosion product for initiation cracking in cover concrete. By implementing the models into a finite element analysis program, a time and space dependent corrosion analysis and a service life prediction of RC structures due to chloride attack are simulated and the results of the analysis are compared with test results. The effect of crack width on the corrosion and the service life of the RC structures are analyzed and discussed.

• 항공우주정책ㆍ법학회지
• /
• 제12권
• /
• pp.246-274
• /
• 2000

This paper discusses the qualification criteria for international hub airport and suggests the strategies for Inchon International Airport (IIA) to be the hub airport in the East Asia. Recently, many East and Southeast Asia countries have invested on large scale international airports like Chap Lak Kok airport, Pudong airport etc.. as Korea have done on IIA. IIA to be open in 2001 will face a serious competition with these airport. Being a hub airport requires geographic proximity. sufficient volume of local traffic. uncongested infrastructure, a good accessibility to surrounding industrial centers. high quality of service to the airline. In order to promote airlines to land at IIA. Korea Government need to establish Open Sky Policy to many countries and national flag carriers of Korea need to be involved in a global alliance. Developing vicinity of IIA as free trade zone will generated more local traffic which makes IIA as more attractive candidate for airlines. The Korea airspace is one of the most restricted area in the world becuase of the national security. which limits civil aircraft maneuvers. The airspace need to be re-structured to exploit the full capacity of IIA.

• 경영과학
• /
• 제14권1호
• /
• pp.107-129
• /
• 1997

Demand for new information services is ever increasing as information technology advances in an unprecedented pace. Capabilities of information technology to overcome the time and space limitations enables efficient storage and processing of a large volume of data shared by many users in geographically dispersed areas. As the users ask for more useful information services, it is necessary to develop information services tp meet the needs of users. Enhancing information services is also necessary to cope actively with the pressures to open the information service is also necessary to cope actively with the pressures to open the information and telecommunications market as the level of Korean information services industry is still in its infancy. Value Added Network(VAN) services have a tremendous growth potential and its economic and social impact would be great as the information society matures. This study suggests a direction for the development of value added and new-media services based on the survey of individual and business users of information services.

• 한국경영과학회지
• /
• 제14권1호
• /
• pp.107-107
• /
• 1989

Demand for new information services is ever increasing as information technology advances in an unprecedented pace. Capabilities of information technology to overcome the time and space limitations enables efficient storage and processing of a large volume of data shared by many users in geographically dispersed areas. As the users ask for more useful information services, it is necessary to develop information services tp meet the needs of users. Enhancing information services is also necessary to cope actively with the pressures to open the information service is also necessary to cope actively with the pressures to open the information and telecommunications market as the level of Korean information services industry is still in its infancy. Value Added Network(VAN) services have a tremendous growth potential and its economic and social impact would be great as the information society matures. This study suggests a direction for the development of value added and new-media services based on the survey of individual and business users of information services.

• 대한교통학회지
• /
• 제33권1호
• /
• pp.29-39
• /
• 2015

현재 보행자도로의 LOS분석 방법은 한국도로용량편람(2013)의 보행자시설편에서 제공하고 있다. 그러나 용량편람에서 제시하는 보행자도로의 분석방법을 적용하여 LOS를 산출할 경우, 분석지점의 대부분이 A수준으로 산출되어 현실적인 보행자도로의 서비스 수준을 반영하지 못하고 있는 실정이다. 이에 본 연구는, 2009년 조사된 '서울시 유동인구조사' 자료를 바탕으로 현재 도로용량편람에서 제시하는 보행자도로의 MOE를 적용하여 LOS기준의 적정성과 문제점을 파악하고, 보다 개선되어진 LOS기준을 제시하고자 하였다. 이의 개선방안으로 본 연구에서는 표준인체치수의 최신화, 보행점유공간의 여유폭 고려, Fruin과 Hall의 연구에서 제시하는 LOS의 정성적인 정의를 활용하여 새로운 기준을 제시하였다. 새로운 기준의 적용결과 종전의 보행자도로 LOS판단 기준보다 합리적인 결과를 보였으며, 본 연구 결과를 바탕으로 추후 보행자도로에 관한 현실적이고 다양한 계획 설계 시공이 가능할 것으로 판단된다.

• 한국항공우주학회지
• /
• 제50권4호
• /
• pp.277-285
• /
• 2022

뉴스페이스 시대를 대표하는 소형위성 분야에서 발사기회에 대한 수요가 크게 증가하고 있다. 이를 위한 소형위성 전용 발사서비스를 합리적인 가격에 제공하는 것은 많은 스타트업 기업들이 추구하는 새로운 비즈니스 모델이 되고 있으며, 여기에는 저비용 부품과 대량생산, 최적화된 제작 공정이 결합된 비용 절감을 위한 혁신적인 솔루션들이 요구되고 있다. 이러한 흐름 속에서 우리나라에서도 한국항공우연구원에서 제3차 우주개발 진흥 기본계획에 따라 누리호를 통해 개발된 액체로켓엔진 기술을 기반으로 2단형 소형발사체 개발에 대비하여 핵심기술 및 비용절감 기술들을 개발하기 위한 선행기술 연구에 착수하였다. 본 논문에서는 소형위성을 위한 혁신적이며 가격 경쟁력을 가지는 것을 목표로 하는 2단형 소형발사체의 개념을 소개하고, 스테이징 설계 및 2단형 발사체의 전기체 구성안을 포함한 임무설계 결과를 기술하였다.

• 한국ITS학회 논문지
• /
• 제13권5호
• /
• pp.1-10
• /
• 2014

본 연구는 미시적 교통류 시뮬레이션 모형을 이용하여 양방향 좌회전차로의 설치기준과 관련된 두 개의 주요한 파라미터를 분석하고 평가하는데 초점을 맞추고 있다. 첫째는 통상적으로 평균 일교통량(ADT)에 기반을 두고 산정되지만 최근 우리나라 도로교통량의 시간변화 특성을 반영한 설계시간 교통량(DHV)의 범위에 대한 분석이며, 다른 하나는 양방향 좌회전차로 내의 구간으로써 양방향 좌회전 수요가 공간점유를 위해 서로 경쟁하면서 상충이 유발되는 부분인 접근로 간격에 관한 것이다. 이에 더해 VISSIM S/W에 VISVAP과 같은 추가 기능 프로그램을 사용하여 TWLTL의 작동을 구현하는 구체적 방법과 절차에 대해 선행 연구들과는 달리 충실히 설명하고자 하였다. 10개의 교통량 수준 시나리오로 수행한 모의실험 결과에 따르면 통과 교통량이 많을수록 좌회전 차량이 경험하는 지체는 예상대로 견조히 증가하였다. 시나리오 대부분에 대한 지체 값이 비신호교차로 서비스수준을 기준으로 LOS C와 D의 범위에 있는 것으로 나타났으며, 교통량 수준 7(중방향으로 3차로 시설 경우 1,116대/시, 5차로 시설은 1,860대/시)까지 양방향 좌회전 차로가 운영가능하다는 것을 알 수 있었다. 이 범위의 교통량은 우리나라 2차로 및 4차로도로 교통량의 상당 부분을 포함하는 것으로 향후 양방향 좌회전차로의 도입 가능성을 한 층 높이는 것이라고 판단하고 있다.