• Journal of the Korean Society for Railway
• /
• v.17 no.6
• /
• pp.433-442
• /
• 2014

This paper evaluates the performance of transit assignment algorithms for urban rail networks. The accuracy of the algorithms is essential not just for travel forecasting but also for the area of applications such as the assessment of road vulnerability and the fare adjustments between train operating companies. Nonetheless, the suitability and caveats for the series of computational steps have not yet been much discussed. This study thus considers the characteristics that are appropriate for investigating Seoul rail travelers using three representative transit assignment algorithms: the optimal strategy algorithm, route choice algorithms, and the Dial's algorithm. Both the theoretical foundation and the empirical performance are examined. The results demonstrate that the Dial's algorithm is superior in terms of the theoretical soundness and the computational efficiency.

• Informatization Policy
• /
• v.22 no.1
• /
• pp.96-117
• /
• 2015

With the development of Information and communication technology the demand for intangible products, in this case contents; are increasing rapidly. However, the market for paid contents is relatively un-vitalized and especially the market for business contents, needed for promoting business or work; is even more stagnant. Existing studies seek to vitalize the paid content market by proposing business models from the supplier's aspect. This study carries out a qualitative research, to discover the causes for market non-vitalization of business content from the user's perspective; by conducting in-depth interviews with 125 customers of business contents targeting office workers and independent businessmen. Through the answers of in-depth interviews, in regards of reasons for purchasing/non-purchasing business contents and problems of business content market; the result indicated that value, trust, and quality are the factors that have direct influence on the purchase. The study proposes resolution to all the problems indicated in three influential factors and derived the responsibility of each paid content market participants; the supplier, related government institution, and user.

• Journal of the Korean Society for Library and Information Science
• /
• v.34 no.3
• /
• pp.133-156
• /
• 2000

A fundamental issue to consider when searching Web information is the quality of information itself and of service. If a Quality Information System (QIS) of Digital Library is sought, new measurement criteria and evaluation index for Web information service are required. Reliance on the existing evaluation criteria is not acceptable if data retrieved are not information and the service is only noise to end-user. Applying existing evaluation criteria of online database to Environmental & Energy Engineering Web DB revealed the limitations and provided a practical and case-based information for improvement. No attempt was made to survey comprehensively all of the evaluation methods that could possibly be relevant. Instead, this discussion concentrates on the information service evaluation index being developed in the KDPC Project. The research found that domestic Web-DB service are still woefully insufficient to conduct comprehensive investigations on environmental topics. More qualified and specialized R&D Web information service and the development of new evaluation criteria based on this investigation(research I.) will be discussed in follow-up research II.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2018.05a
• /
• pp.18-18
• /
• 2018

상수관망 시스템(Water Distribution System, WDS)은 이용자에게 양질의 상수도를 공급하기 위해 구축된 사회기반시설물로써, 정수된 물이 사용처에 도달하기까지 송수과정에서 발생 가능한 수질저하를 고려해야 한다. 일반적으로 정수장에서 염소처리를 한 후, 도달시간을 고려한 시스템 내 잔류 염소농도를 유지함으로써 수질저하를 예방한다. 여기서 상수도 내 잔류 염소농도는 미생물 번식 및 관내 부식물 등 다양한 생물 화학적 오염을 효과적으로 예방하는 반면, 과다할 경우 이용자의 음용성을 저해할 수 있어 시스템 전반에 걸쳐 염소농도의 적절한 관리가 요구된다. 특히, 상수관망에서는 공급경로 및 공급량에 따라 각 수요처의 도달 염소농도가 다르게 분포할 수 있으므로, 시설운영자는 균등하고 적절한 염소농도를 유지하기 위해 추가적인 염소 재투입시설을 설치하여 함께 관리하고 있다. 이 때, 염소투입 시설의 운영계획은 EPANET과 같은 상수관망 해석모형의 수질모의를 바탕으로 수립된다. 그러나 일반적으로 수질모의는 수리해석과는 달리 긴 시간이 소요되는 단점이 존재한다. 본 연구에서는 이러한 단점을 개선하기 위해, 특정 네트워크의 수질모의 결과를 학습시킨 인공신경망(ANN) 모형을 구축하고 이를 이용하여 상수관망 수질모의 계산시간을 단축하고자 하였다. 여기서 ANN모형의 학습은 EPANET을 통해 미리 선정된 다양한 염소 투입지점의 염소 투입농도와 용수 공급량 자료, 그리고 주요 관측지점에서 측정된 염소농도자료를 이용하였다. 학습된 ANN모형을 EPANET 수질모의 결과와 비교 및 검증을 실시한 결과, 사전에 소요된 학습시간을 제외하면 수질모의 소요시간 측면에서 큰 개선효과를 보였으며, 대표지점에서의 수질모의 결과가 유사하였다. 추가적으로, 본 연구에서는 학습된 ANN모형과 최적화 알고리즘인 GA(Genitic Algorithm)를 연계하여 상수관망에서의 염소 재투입 스케줄링을 최적화하는 프로그램을 개발함으로써, 안전하고 경제적인 상수관망의 수질운영에 기여하고자 하였다.

• Journal of the Korea Convergence Society
• /
• v.11 no.12
• /
• pp.125-130
• /
• 2020

The Korean maritime industry is growing rapidly as income levels rise. In particular, the domestic yacht market is generating steady market demand, which is a good opportunity for users who want to enjoy leisure. Among them, the experience-type yacht is operated smoothly around Suyeong Bay in Busan. In this study, a survey of experienced yacht users conducted an analysis focusing on color as much as the interior structure. The colors you experience when you stay in a specific space for a short time have a significant impact on the user's satisfaction and sensibility. Often, systematic research into space is often focused on physical distribution. However, color leaves a strong impression on short experiences as much information as it accepts through the optic nerve. A survey of yacht passengers was conducted to derive appropriate adjectives, and the results were obtained after analyzing them by means of I.R.I monochrome and image scale. Afterwards, it is expected that this research will be used as a theoretical basic data that can be used to carry out the production, repair, and repair of hands-on yachts that are developed on their own.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.8
• /
• pp.1238-1247
• /
• 2022

The e-commerce market is growing faster as demand for non-face-to-face shopping increases due to COVID-19. These changes lead to the expansion of various opportunities for consumers, but companies are required to understand consumer characteristics and reflect them in their sales strategies so that they can be competitive in the market. This study examined how the perceived ease and utility of consumers affect the intention to use the platform according to the technology acceptance model (TAM). As a result, it was confirmed that the price competitiveness, awareness, and ease of use of the platform had a significant effect on the utility. In addition, it was confirmed that there was no moderating effect of user characteristics on the effect of ease of use on the platform intention. These results present important implications for a company's sales strategy, and in future studies, it is necessary to expand the study in consideration of more diverse variables.

• The Journal of the Korea Contents Association
• /
• v.22 no.3
• /
• pp.94-104
• /
• 2022

As the audio content market grows due to the spread of the AI speaker market and the influence of connected cars, the demand for podcast service is increasing. Therefore, in this study, the behaviors of podcast users were identified and the user types were classified. In the background study, podcast usage motives and user types were studied, and they were referred to when making the questionnaire. In the survey, preferred audio content was identified according to the situation, and in the in-depth interview, the user type and insights were derived by identifying the audio service usage behavior. As a result of the survey, there was little difference between preferred content for single listening and multitasking, but the difference in preferred content according to time period was statistically significant. The three user types derived from the in-depth interview were divided into users who listen alone for the purpose of study, find and listen to useful information quickly while on the go, and multitask and listen to the light and comfortable contents. It is expected that the results of this study will be an important reference for designing an audio content platform to improve user experience.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.22 no.1
• /
• pp.52-64
• /
• 2023

This paper concentrated on estimating the travel time value of individual regional bus passengers in various in-vehicle crowding conditions. In the analysis model, the traffic-selection data of individual transportation passengers based on smart-card data were used. Variables which reflect the level of in-vehicle crowding and the variables of in-vehicle travel time that reflect the level of in-vehicle crowding were included in the model using Box-Cox transformation. The result of this paper indicates that the travel time value experienced by individual users would increase as the in-vehicle crowding level increases. The smart card data used in this paper is considered to have significant implications in terms of conducting more sophisticated and realistic qualitative research to reflect the values of variables for in-vehicle traffic hours and in-vehicle crowding levels, which previously had limitations in observation and quantification. It is expected that the effects of improvement measures for reducing congestion on regional buses can be considered quantitatively by applying the estimation results of crowding multiplier.

• Convergence Security Journal
• /
• v.24 no.2
• /
• pp.133-140
• /
• 2024

The spread of Direct-to-Consumer (DTC) genetic testing, where users request tests directly, has been increasing. With growing demand, certification systems have been implemented to grant testing qualifications to non-medical institutions, and the scope of tests has been expanded. However, unlike cases in less regulated foreign countries, disease-related tests are still excluded from the domestic regulations. The existing de-identification method does not adequately ensure the uniqueness and familial sharing of genomic information, limiting its practical utility. Therefore, this study proposes the application of fully homomorphic encryption in the analysis process to guarantee the usefulness of genomic information while minimizing the risk of leakage. Additionally, to safeguard the individual's right to self-determination, a privacy preservation model based on Opt-out is suggested. This aims to balance genomic information protection with maintainability of usability, ensuring the availability of information in line with the user's preferences.

• Information Systems Review
• /
• v.23 no.4
• /
• pp.87-102
• /
• 2021

Smart cities are attracting attention as a new economic growth engine based on new technologies and means to solve side effects of urbanization such as a surge in energy consumption, deepening environmental pollution, and an increase in crime rates. In particular, as demand for non-face-to-face services increases due to COVID-19, the role of smart cities that can provide various online and offline non-face-to-face services is becoming more important. Therefore, this study defined smart city non-face-to-face services based on literature research on the concept and underlying technology of smart city, and analyzed consumer utility for each service using Conjoint analysis. In particular, differences in user preferences between Sejong City and Busan City, which are currently designated as national smart city pilot cities in Korea, were compared and analyzed, and based on the derived results, measures to improve the competitiveness of smart city services were suggested.