• Journal of Digital Convergence
• /
• v.19 no.12
• /
• pp.165-173
• /
• 2021

The purpose of this study was to provide directions to help enter and expand long-distance routes by analyzing the characteristics of AirAsia X's network construction with Malaysia Airlines. To this end, long-distance route data was extracted from the OAG Schedule Analyzer and the network was analyzed on a two-period basis using SNA. Since AirAsia X's entry into long-range routes, Malaysia Airlines has steadily reduced its routes across the entire region. On the other hand, it is analyzed that AirAsia X is building an expanded network by increasing its network in Northeast Asia instead of ultra-long range routes. Studies have shown that LCCs also have potential growth in the long-distance route market of less than 7,000 km. The results of this study may help LCC establish a long-distance market entry and network deployment strategy.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.30 no.4
• /
• pp.23-32
• /
• 2022

Prototype UAMs are shown to us in the market. When the complete product is delivered to market, the efficiency of each UAMs can be compared by default. Before the complete product is shown to us, the comparative study on efficiency of UAMs is performed under the product cost estimation. The efficiency analysis result reveals that both of Lift & Cruise type and vectored thrust type show good efficiency at the initial stage of product. At the near terms stage, five years later from initial stage end, efficiency gets some change. Vectored thrust type of UAMs show best efficiency at the near term stage of product. Because UAMs will be used in urban area, Seoul is the place where the UAMs will be used first. The flying route from Seoul City Hall to Yongsan Park, National Assembly in Yeouido, and City Airport is no more than 10 km distance. For this short distance route, efficiency will make multi-rotor type UAM be prefered to other types. For long distance route or commuting route, life & cruise type and vectored thrust type of UAMs will be prefered on account of operational efficiency.

• Journal of Environmental Impact Assessment
• /
• v.17 no.2
• /
• pp.133-141
• /
• 2008

The loss, alteration, and fragmentation of habitat have led to a reduction of biodiversity. The growing awareness of the negative effects of habitat fragmentation on natural systems has resulted in conservation strategy that is concerned with not only population and habitat level but also ecosystem and landscape level. Especially, ecological network to link core areas or major habitat patches is one of the most important issues. Recently, landscape connectivity is increasingly used in decision making for fragmented landscape management in order to conserve the biodiversity in the regional scale. The objective of this study was to find potential forest as a ecological corridor in Go-yang city, Gyung-gi province using cost-distance modelling method that can measure connectivity based on animal movement. 'Least cost-distance' modelling based on functional connectivity can be useful to establish ecological network and biodiversity conservation plan. This method calculates the distance modified with the cost to move between habitat patches based on detailed geographical information on the landscape as well as behavioural aspects of the animal movement. The least cost-distance models are based on two biologically assumptions: (1) dispersers have complete knowledge of their surroundings, and (2) they do select the least cost route from this information. As a result of this study, we can find wildlife moving route for biodiversity conservation. The result is very useful for long-term aspect of biodiversity conservation plan in regional scale, because this is reflection of geographical information and behavioural aspects of the animal movement.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.3D
• /
• pp.361-366
• /
• 2006

It is widely known that the dynamic optimal path algorithm, adopting real-time path finding, can be supporting an optimal route with which users are satisfied economically and accurately. However, this system has to search optimal routes frequently for updating them. The proposed concept of optimizing search area lets it reach heuristic optimal path rapidly and efficiently. Since optimal path should be increased in proportion to an distance between origin and destination, tremendous calculating time and highly efficient computers are required for searching long distance journey. In this paper, as a result of which the concepts of partial solution and representative path are suggested. It was possible to find an optimal route by decreasing a half area in comparison with the previous method. Furthermore, as the size of the searching area is uniform, comparatively low efficient computer is required for long distance trip.

• The Research Journal of the Costume Culture
• /
• v.21 no.5
• /
• pp.780-791
• /
• 2013

This paper is concerned with the development of the silk trade and in particular with silk-ikat production. Early origins are explained and issues relating to the development of long-distance trade are discussed. The principal trading participants are identified and the focus is turned to silk-ikat production in Central Asia. It is recognised that the vast bulk of trade, along what became known as the 'Silk Route' (or 'Silk Road'), did not involve straight-forward or direct exchange between powers to the far east of the route and powers to the far west, but rather was done in stages between adjacent or not too distant locations. Diffusion of ideas was not therefore immediate and operational at one eastern or western extreme of a trading network but, rather, was a gradual process influencing adjacent participants, at stages between the geographic extremes over a long period of time.

• Journal of Korea Trade
• /
• v.25 no.8
• /
• pp.57-74
• /
• 2021

Purpose - This study aims to analyze the characteristics of network construction by Norwegian Air and AirAsia X, which are recognized as leading airlines in the long-haul LCC market. Based on this analysis, this study intends to provide implications for networking strategies for Korean LCCs that seek to enter the long-haul market when the aviation market stabilizes again upon the end of the COVID-19 pandemic. Design/methodology - To conduct the network analysis on long-haul low-cost airlines, the Official Airline Guide (OAG) Schedule Analyzer was used to extract long-haul data of Norwegian Air and AirAsia X. To analyze the trend of the long-haul route network, we obtained the data from 3 separate years between 2011 and 2019. The network was analyzed using UCINET 6.0 in order to examine the network structure of long-haul low-cost airlines and the growth trend of each stage. Findings - Analyzing the network of long-haul routes by visualizing the network structure of low-cost carriers showed the following results. In its early years, Norwegian Air's long-haul route network, centering on regional airports in Spain and Sweden, connected European regions, the Middle East, and Africa. As time passed, however, the network expanded and became steadily strong as the airline connected airports in other European countries to North America and Asia. In addition, in 2011, AirAsia X showed links to parts of Europe, such as London and Paris, the Middle East and India, and Australia and Northeast Asia, centering on the Kuala Lumpur Airport. Although the routes in Europe were suspended, the network continued to expand while concentrating on routes of less than approximately 7,000 km. It was found that instead of giving up on ultra-long-haul routes such as Europe, the network was further expanded in Northeast Asia, such as the routes in Korea and Japan centering on China. Originality/value - Until the COVID-19 pandemic broke out, Norwegian Air actively expanded long-haul routes, resulting in the number of long-haul routes quintupling since 2011. The unfortunate circumstance, wherein the world aviation market was rendered stagnant due to the outbreak of COVID-19, hit Norwegian Air harder than any other low-cost carriers. However, in the case of AirAsia X, it was found that it did not suffer as much damage as Norwegian Air because it initially withdrew from unprofitable routes over 7,000 km and grew by gradually increasing profitable destinations over shorter distances. When the COVID-19 pandemic ends and the aviation market stabilizes, low-cost carriers around the world, including Korea, that enter the long-haul route market will need to employ strategies to analyze the marketability of potential routes and to launch the routes that yield the highest profits without being bound by distance. For stable growth, it is necessary to take a conservative stance; first, by reviewing the business feasibility of the operating a small number of highly profitable routes, and second, by gradually expanding these routes.

• Journal of Urban Science
• /
• v.11 no.2
• /
• pp.9-17
• /
• 2022

The purpose of this study is to develop an index for evaluating the function of a new motorway using the travel distance frequency distribution (TLFD) calculated using the vehicle travel route big data, and to overcome the limitations of the evaluation through the existing traffic volume. The mobility evaluation index of motorways was developed by applying it to the TLFD data table in 2019. The smaller the value of the mobility evaluation index of the link is calculated, the more it is a link with mainly short-distance travel, and the higher the value of the mobility evaluation index, the more it means a link with mainly long-distance travel. The accessibility evaluation index was calculated through the result of the mobility evaluation index of all motorways developed, and all motorways were grouped into three groups using K-means clustering. Group A was found to exist inside a large city and consisted of motorways with many short-distance traffic, Group B was investigated as acting as an arterial between groups, and Group C was classified as a motorway consisting mainly of long-distance traffic connecting large cities and large cities. This study is significant in developing a new motorway function evaluation index that can overcome the limitations of motorway function evaluation through the existing traffic volume. It is expected that this study can be a reasonable comprehensive indicator in the operation and planning process of motorways.

• ETRI Journal
• /
• v.6 no.2
• /
• pp.15-17
• /
• 1984

A long-wavelength ($1. 3\mum$) multimode fiber-optic transmission system has been developed and the field trial system has been installed over 17.3km distance in Daejeon Area by KETRI. The 45Mb/s and 90Mb/s system operate with BER $10^-9$over 17.3km distance, and they successfully operate on the route of 34. 6km length when the fiber cable is simply connected at one end. Average loss of the fiber cable shows 0. 81dB/km including splice loss and the average bandwidth over the 17. 3km distance is 170MHz.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2007.05a
• /
• pp.1283-1285
• /
• 2007

A wireless sensor network is the combination of a large number of deployed sensors over an area. Communication between the sensors is the most important factor for a successful sensor network. It is mandatory that long distance and multi-hop communication will occur between sensors. Generally sensors relay the sensed data of a particular territory to the command center via a base station. For the non uniformed deployment of sensors many sensors may deploy in hostile areas surrounded by full of obstacles or in other condition it may be out of the direct communication range of the base station. It seems a critical problem for routing data to and from those sensors to the base station. This paper proposes a route management scheme using a dynamic load balancing approach based on residual energy of each agent sensors.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.19 no.4
• /
• pp.71-76
• /
• 2019

Research on indoor location tracking technology using smartphone is actively being carried out. Especially, the movement distance of the smartphone should be accurately measured and the movement route of the user should be displayed on the map. Location tracking technology using sensors mounted on smart phones has been used for a long time, but accuracy is not good enough to measure the moving distance of the user using only the sensor. Therefore, when the user moves the smartphone in a certain posture, it must research and develop an appropriate algorithm to measure the distance accurately. In this paper, we propose a method to reduce moving distance estimation error by removing user 's foot shape by limiting the screen of smartphone in pyramid - based optical flow estimation method.