• Journal of Aerospace System Engineering
• /
• v.6 no.3
• /
• pp.19-23
• /
• 2012

"The FAA's Next Generation Air Transportation System" is a comprehensive overhaul of U.S National Airspace System to make air travel more convenient and dependable, while ensuring the flight is as safe, secure and hassle-free as possible. At its most basic level, NextGen represents an evolution from a ground-based system of air traffic control to a satellite-based system of air traffic management. This evolution is vital to meeting future demand, and to avoiding gridlock in the sky and at U.S airports. NextGen will open worldwide's skies to continued growth and increased safety while reducing aviation's environmental impact.

• Journal of Korean Society of Transportation
• /
• v.19 no.4
• /
• pp.85-96
• /
• 2001

This paper discusses the problem of finding the Origin-Destination(O-D) shortest path in urban road networks that have variable special qualifies such as time windows for passing as well as geometrical special qualities such as U-turn and left-turn prohibition. The focus of this paper is motivated by the problem of finding minimum travel time paths for an advanced traveler information system (ATIS) in the context of intelligent transportation system(ITS) application. The transportation network with variable and geometrical special qualities is a more realistic representation of the urban road network in the real word. But, the traditional and existing shortest path algorithms can not search practical shortest path that variable special quality is reflected. This paper presents a shortest path algorithm which can search reasonable shortest path information for the urban ATIS application within a real time. The algorithm is based on genetic algorithm(GA). The high performance of the proposed algorithm is demonstrated by computer simulations.

• International Commerce and Information Review
• /
• v.19 no.1
• /
• pp.213-234
• /
• 2017

This study analyzed valid samples of 707 units collected by conducting paper and online surveys on the Korean, the Chinese, the American, and the Japanese. The result showed that a significant causal relationship exists between power distance and pull motivation as well as collectivism and push motivation, which led to a conclusion that developing travel packages that can strengthen bonding of fraternal societies through various events and attractions is effective for respondents from Asian countries. On the other hand, Americans turned out to prefer practical plans, which could provide individual's needs and preferences, for example, a self-healing package. This study, using a simple survey, may have a limitation in that it does not allow the participants to express their opinions. However, the study is meaningful that it made a theoretical contribution utilizing Hofstede's cultural dimensions index, two types of motivation, and theories of customer satisfaction and revisit intention. It also has a practical implication in that it proposes the most optimal and applicable overseas travel marketing strategy by comparing cultural traits of each country.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.11
• /
• pp.2575-2580
• /
• 2013

In this paper, we watch out key measure of the level of transportation service about travel time and delay time. And we measured vehicle traffic by moving vehicle method using CCTV which is one of the travel time measure. We should be measured in place of continuous traffic flow characteristics with wide traffic light interval. In addition, traffic flow on the other side of the interval must be sufficiently identifiable and at the end of this section must be possible U-turn. This method it requires only the driver of the vehicle because of the CCTV measure. In addition, We cannot require time, distance, and traffic equipment that can be recorded. Because equipped with the software to do that. In addition to traffic, average travel time, average space speed, traffic density are also available.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1219-1222
• /
• 2005

As the optical communication is introduced to the backbone network at first and becomes a general communication method of network, the demand of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, and WDM(Wavelength Division Multiplexing) element increases. The alignment and the attachment technology are very important in the fabrication of optical elements. In this paper, the driving mechanism of ultra precision stage is studied with the aim of optimal design of stage. The travel and the resolution of stage are investigated. The hysteresis of the stage is generated because of PZT actuator. The hysteresis and the inverse hysteresis are modeled in X, Y, and Z-axis motion. The input data of desired displacement to the stage according to input voltage is obtained from the inverse hysteresis equation. In the result of experiments with the input data, the errors due to hysteresis are well compensated.

• Journal of Biosystems Engineering
• /
• v.13 no.2
• /
• pp.1-8
• /
• 1988

A scale model of power tiller-trailer system with the same kinematic characteristics was constructed one eighth of the actual size to validate the effectiveness of mathematical model of motion. The parameters for the scale model of power tiller-trailer system were measured by a series of laboratory experiments. Validation tests for the: scale model was conducted under several ground and operating conditions. The tests were performed on artificial ground surfaces with several kind, of slope and obstacle. The travel path of the scale model was photographed successively in three directions. The travel paths obtained from both the film analysis and the simulation model appeared to be consistent with each other. It was concluded that the simulation model could be used to predict the motion of actual power tiller-trailer system if the parameters for actual power tiller and trailer are provided.

• Journal of Smart Tourism
• /
• v.1 no.1
• /
• pp.53-64
• /
• 2021

Upselling is often a critical factor in revenue generation for businesses in the tourism and travel industry. Utilizing passenger data from a major international airline company, we develop the PAX (Passenger, Airline, eXternal) model to predict passengers that are most likely to accept an upgrade offer from economy to premium. Formulating the problem as an extremely unbalanced, cost-sensitive, supervised binary classification, we predict if a customer will take an upgrade offer. We use a feature vector created from the historical data of 3 million passenger records from 2017 to 2019, in which passengers received approximately 635,000 upgrade offers worth more than $422,000,000 U.S. dollars. The model has an F1-score of 0.75, outperforming the airline's current rule-based approach. Findings have several practical applications, including identifying promising customers for upselling and minimizing the number of indiscriminate emails sent to customers. Accurately identifying the few customers who will react positively to upgrade offers is of paramount importance given the airline 'industry's razor-thin margins. Research results have significant real-world impacts because there is the potential to improve targeted upselling to customers in the airline and related industries.

• Journal of Families and Better Life
• /
• v.20 no.3
• /
• pp.139-156
• /
• 2002

The purpose of this study is to compare the patterns of time use between Korean and USA families. The data for 353 Seoul-based Korean families with two children living in Seoul and 130 USA families with two children living in the State of Utah were collected using a structured questionnaire and time diary. The major findings were as the following: 1. The Korean couples spent more time at personal care, paid work, and travel than the USA couples did, while the USA couples spent more time at housework and social-cultural activities than the Korean couples did. 2. The Korean wives spent more time doing food and clothing related housework than the USA wives did. Compared with the Korean wives, however, the time spent at house cleaning and management, family care and shopping and home management were longer than USA wives. The time U.S. husbands engaged in housework was much greater than by the Korean husbands. 3. Regardless of sex and school level, the Korean children spent less time at sleeping/rest, housework and socio-cultural activities and more time at eating and learning than those of U.S. These time use patterns of the families in both countries may reflect the differences of the cultural contexts, social norms, life styles, and the degrees of urbanization. To fully explain the findings, further study on the differences in social and cultural factors between the two countries is needed.

• Current Industrial and Technological Trends in Aerospace
• /
• v.8 no.2
• /
• pp.24-30
• /
• 2010

Space solar sails are a form of spacecraft propulsion using the radiation pressure of light from a star or laser to push enormous ultra-thin mirrors to high speeds. With respect to it, U.S.A, Japan, E.U. and Russia, etc. have performed a substantial research and the space flight test. On May 2010, JAXA succeeded in launching the world's first interplanetary solar sail spacecraft "IKAROS" to Venus. Currently, solar sail propulsion is aimed chiefly at accomplishing a number of non-crewed missions in any part of the solar system and beyond. This paper presents the technology trend of advanced countries on the development of the solar sails as a new propulsion method for the space investigation and travel.

• Korean Security Journal
• /
• no.38
• /
• pp.33-56
• /
• 2014

This study is aim to make use of prevention of air terrorism and strengthen of air security in Korea. To achieve it. searching main feature in U.S aviation profiling. Aviation profiling in U.S used to Secure Flight, Screening Passengers by Observation Technique, Registered Travel Program. Through U.S Aviation Profiling, Prevention of air terrorism in Korea are as in the following. First, Through U.S Aviation Profiling, Information of terrorism constructed in advance and unification of constructed information. Second, Identifiying that institution exclusively for prevention of air terrorism. Third, Identifiying that human rights and privacy invasion to a minimun plan anout U.S aviation profiling. Finally, Identifiying that the spread of research development for prevention of air terrorism and strengthen of air security in Korea.