• International Journal of Internet, Broadcasting and Communication
• /
• v.15 no.2
• /
• pp.268-272
• /
• 2023

With the development of SNS, companies and individuals are actively marketing through social media to develop their own products. It is also important to post posts promoting on simple SNS or to show a lot of exposure using algorithms, but customers upload reviews or proof shots of the product on their own, naturally increasing the exposure of the product and increasing the purchasing power of potential customers. As the number of products that users want to purchase through SNS is increasing, they want to access and purchase not only tangible products such as goods and food, but also intangible services through SNS. In this paper, we would like to study exhibitions that have both tangible and intangible characteristics. SNS accounts that mainly introduce these products by searching for reviews have been created while spending leisure time such as exhibitions and fairs, reducing the hassle of searching for personal interests on search engines, and providing prices and reviews from the exhibition's schedule, lowering entry barriers and increasing purchasing power. Using this point, many exhibitions not only display works, but also open various experience centers, and create a photo zone or a unique exhibition hall atmosphere to attract many customers. In this study, we study the impact of SNS on the leisure culture of exhibition. The marketing direction in the situation where SNS marketing is becoming the mainstream is presented, and the change in the form of exhibition is described and presented as an academic approach.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.5D
• /
• pp.739-746
• /
• 2006

The bus probe-based link travel times were more readily available due to bus' fixed route schedule and it was different from that of taxi-based one in its value for the same link. At the same time, the bus-based one showed less accurate information than the taxi-based link travel time, in terms of reliability expressed by 1-RMSE(%) measure. The purpose of this thesis is to develop a heuristic algorithm for mixing both sources-based link travel times. The algorithm used both real-time and historical profile travel times. Real-time source used 4 consecutive periods' average and historical source used average value of link travel time for various congestion levels. The algorithm was evaluated for Seoul urban arterial network 3 corridors and 20 links. The results based on the developed algorithm were superior than the mere fusion based link travel times and the reliability amounted up to 71.45%. Some limitation and future research agenda have also been discussed.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.7B
• /
• pp.685-696
• /
• 2004

Real-time multimedia applications that require large amount of bandwidth need resource reservation before starting service for providing the QoS(i.e., Quality of Service). To reserve resources in advance, each reservation request has to notify its expectation on the required amount of resources and service duration. Using this information, a resource manager can schedule advance reservations. However, most existing resource management systems are adopting straightforward call admission control process (i.e., only immediate reservation) by checking currently available resources without considering the service duration. Hence, the resource management system that supports advance reservation has to manage confliction caused by indefinite service duration of immediate reservation. Even though the separation of resource pool according to type of reservation can prevent the confliction, it causes low resource utilization. In this paper, we propose an effective resource management scheme that supports both immediate and advance reservations by sharing resources dynamically. Using network cost function, the proposed scheme determines and adaptively adjusts resource boundary according to the confliction rate by varying weight parameters. And also, we define user utility function to quantify user satisfaction based on how well the reserved resource is guaranteed during service time. Simulation results using NS-2 network simulator show that the proposed scheme can achieve better resource utilization with preferable QoS than other schemes like static resource partitioning.

• Journal of Korean Society of Transportation
• /
• v.26 no.5
• /
• pp.117-127
• /
• 2008

After the deregulation of the aviation market in the United States in 1978, airlines took advantage of the possibilities of the liberalized market and reorganized their networks. Then, the hub-and-spoke networks became widely used in the aviation market. The framework of hub-and-spoke network made it feasible to amplify flight networks. Thus, a number of airlines were able to fly to more destinations than ever before through the networks. Amplification of networks can be implementing through the transfer of passengers, transshipment of cargo, or both most researches have been concentrated on the passenger aspect at airports worldwide. Air cargo, however, has become one of the most significant areas at hub airports to keep their leading position in terms of the provision of services and handling volumes. This paper investigates the connectivity of airfreight networks as the temporal concentrations in current network at Incheon International Airport. In order to evaluate airline flight schedule effects to stimulate hubbing at an airport, the indirect connectivity can be considered to be the number of direct frequencies, the minimum connecting times and the quality of the connection determine indirect connectivity. Therefore the connectivity of freight transshipment depends on both the quality of the connection at the hub airport and the quality of the indirect flight compared to the direct flight. In addressing these issues, this paper analyzes the connectivity of flight schedules using a temporal wave-system structure and estimates the degree of connectivity and quality of connectivity applying the NETSCAN model.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.20 no.3
• /
• pp.129-139
• /
• 2009

Objectives : This study evaluated the effectiveness of school-based mental health screening and treatment linkage programs, focusing on attention-deficit hyperactivity disorder (ADHD) and adolescent depression. Methods : All 11,158 children and adolescents aged 8-14 years in Seoul received a school-based mental health screening, consisting of the Korean versions of the ADHD rating scale and the Child Behavior Checklist (CBCL), for ADHD, and the Center for Epidemiological Studies Depression Scale (CES-DS) and the Suicidal Ideation Questionnaire-Junior (SIQ-JR), for depression. The high-risk children's and adolescents' diagnoses were confirmed using the Diagnostic Interview Schedule for Children-IV (DISC-IV). Treatment linkage programs were managed by the Seoul Metropolitan Community Mental Health Center (Program 1), the Seoul Metropolitan Office of Education (Program 2), or the Dongjak District Office of Education (Program 3). We estimated and compared the referral rates of the three programs. Results : Program 1 screened and referred 22.9% of ADHD youths to mental health services, Program 2, 68.8%, and Program 3, 40.0%. Program 1 screened and referred 22.8% of depressed youths to mental health services, Program 2, 53.8%, and Program 3, 88.9%. Key elements for successful screening and referral programs were an effective school/community mental health center/Office of Education network, the parents' financial support and perception of their child's mental health status as being problematic, and the teachers' active engagement. Conclusion : This is the first study investigating the effectiveness of school-based mental health screenings' linkage to treatment for primary and middle school students in Korea. An effective network for community mental health and improvements in parents' and teachers' perceptions regarding mental health are needed for more successful treatment linkage.

• Journal of Korean Society for Geospatial Information Science
• /
• v.19 no.4
• /
• pp.119-126
• /
• 2011

During precise survey on the top of High rise buildings and civil structures, optical surveying equipments like a Total Station are not recommended to use because of some reasons that uneasier alignment with reflectors located at the top of building, increasing error depends on increasement of observation distance and unavailable dynamic positioning etc. Recently various GPS positioning methods have been applied to this job however almost of them are post-processing method which is required much longer time during for whole process includes stake-out, cross checking, fixing positions and final inspections. Therefore, in this study, we applied with RTK surveying system which allows stake-out and inspection in realtime to avoid delaying of construction schedule and also applied with Quasi Static RTK measurement and network adjustment to get a high accuracy within a few millimeters in structure positioning to achieve a successful management for process and quality control of the project. As a result, very high accurate surveying for structures within approx. 2mm in realtime has been achieved when surveyor conduct a network adjustment using least square method for 4 base lines created by Quasi Static RTK data and we expect this method will be applied to construction survey for high rise buildings and civil structures in the future.

• Journal of Korean Society of Transportation
• /
• v.27 no.1
• /
• pp.143-155
• /
• 2009

A dynamic traffic assignment (DTA) has recently been implemented in many practical projects. The core of dynamic model is the inclusion of time scale. If excluding the time dimension from a DTA model, the framework of a DTA model is similar to that of static model. Similar to static model, with given exogenous travel demand, a DTA model loads vehicles on the network and finds an optimal solution satisfying a pre-defined route choice rule. In most DTA models, the departure pattern of given travel demand is predefined and assumed as a fixed pattern, although the departure pattern of driver is changeable depending on a network traffic condition. Especially, for morning peak commute where most drivers have their preferred arrival time, the departure time, therefore, should be modeled as an endogenous variable. In this paper, the authors point out some shortcomings of current DTA model and propose an alternative approach which could overcome the shortcomings of current DTA model. The authors substitute a traditional definition for time-dependent OD table by a new definition in which the time-dependent OD table is defined as arrival time-based one. In addition, the authors develop a new DTA model which is capable of finding an equilibrium departure pattern without the use of schedule delay functions. Three types of objective function for a new DTA framework are proposed, and the solution algorithms for the three objective functions are also explained.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.11
• /
• pp.11-18
• /
• 2014

Most of the energy efficient MAC protocols for wireless sensor networks (WSNs) are based on duty cycling in a single channel and show competitive performances in a small number of traffic flows; however, under concurrent multiple flows, they result in significant performance degradation due to contention and collision. We propose a multi-channel pipelining (MCP) method for convergecast WSN in order to address these problems. In MCP, a staggered dynamic phase shift (SDPS) algorithms devised to minimize end-to-end latency by dynamically staggering wake-up schedule of nodes on a multi-hop path. Also, a phase-locking identification (PLI) algorithm is proposed to optimize energy efficiency. Based on these algorithms, multiple flows can be dynamically pipelined in one of multiple channels and successively handled by sink switched to each channel. We present an analytical model to compute the duty cycle and the latency of MCP and validate the model by simulation. Simulation evaluation shows that our proposal is superior to existing protocols: X-MAC and DPS-MAC in terms of duty cycle, end-to-end latency, delivery ratio, and aggregate throughput.

• The Korean Journal of Air & Space Law and Policy
• /
• v.32 no.1
• /
• pp.83-138
• /
• 2017

Korea-China FTA entered into force on the 20th of December 2015, and one year elapsed after its effectuation as the FTA with China, our country's largest trading partner. Therefore, this study looks at the trends of air transport trade between Korea and China, and examines the contents of concessions to the air transport services sector in Korea-China FTA, and analyzes the impact on the air transport sector by Korea-China FTA, and proposes our country's aviation policy direction in order to respond to such impact. In 2016 the trends of air transport trade between Korea and China are as follows : The export amount of air transport trade to China was 40.03 billion dollars, down by 9.3% from the last year, and occupied 32.2% of the total export amount to China. The import amount of air transport trade from China was 24.26 billion dollars, down by 9.1% from the last year, and occupied 27.7% of the total import amount from China. The contents of concessions to the air transport services sector in Korea-China FTA are as follows : China made concessions to the aircraft repair and maintenance services and the computer reservation system services with limitations on market access and national treatment in the air transport services sector of the China Schedule of Specific Commitments of Korea-China FTA Chapter 8 Annex. Korea made concessions to the computer reservation system services, selling and marketing of air transport services, and aircraft repair and maintenance without limitations on market access and national treatment in the air transport services sector of the Korea Schedule of Specific Commitments of Korea-China FTA Chapter 8 Annex. The impact on the air transport sector by Korea-China FTA are as follows : As for the impact on the air passenger market, in 2016 the arrival passengers of the international flight from China were 9.96 million, up by 20.6% from the last year, and the departure passengers to China were 9.90 million, up by 34.8% from the last year. As for the impact on the air cargo market, in 2016 the exported goods volumes of air cargo to China were 105,220.2 tons, up by 6.6% from the last year, and imported goods volumes from China were 133,750.9 tons, up by 12.3% from the last year. Among the major items of exported air cargo to China, the exported goods volumes of benefited items in the Tariff Schedule of China of Korea-China FTA were increased, and among the major items of imported air cargo from China, the imported goods volumes of benefited items in the Tariff Schedule of Korea of Korea-China FTA were increased. As for the impact on the logistics market, in 2016 the handling performance of exported air cargo to China by domestic forwarders were 119,618 tons, down by 2.1% from the last year, and the handling performance of imported air cargo from China were 79,430 tons, down by 4.4% from the last year. In 2016 the e-commerce export amount to China were 109.16 million dollars, up by 27.7% from the last year, and the e-commerce import amount from China were 89.43 million dollars, up by 72% from the last year. The author proposes the aviation policy direction of Korea according to Korea-China FTA as follows : First, the open skies between Korea and China shall be pushed ahead. In June 2006 Korea and China concluded the open skies agreement within the scope of the third freedom and fourth freedom of the air for passenger and cargo in Sandong Province and Hainan Province of China, and agreed the full open skies of flights between the two countries from the summer season in 2010. However, China protested against the interpretation of the draft of the memorandum of understanding to the air services agreement, therefore the further open skies did not take place. Through the separate aviation talks with China from Korea-China FTA, the gradual and selective open skies of air passenger market and air cargo market shall be pushed ahead. Second, the competitiveness of air transport industry and airport shall be secured. As for the strengthening methods of the competitiveness of Korea's air transport industry, the support system for the strengthening of national air carriers' competitiveness shall be prepared, and the new basis for competition of national air carriers shall be made, and the strategic network based on national interest shall be built. As for the strengthening methods of the competitiveness of Korea's airports, particularly Incheon Airport, the competitiveness of the network for aviation demand creation shall be strengthened, and the airport facilities and safety infrastructure shall be expanded, and the new added value through the airport shall be created, and the world's No.1 level of services shall be maintained. Third, the competitiveness of aviation logistics enterprises shall be strengthened. As for the strengthening methods of the competitiveness of Korea's aviation logistics enterprises, as the upbringing strategy of higher added value in response to the industry trends changes, the new logistics market shall be developed, and the logistics infrastructure shall be expanded, and the logistics professionals shall be trained. Additionally, as the expanding strategy of global logistics market, the support system for overseas investment of logistics enterprises shall be built, and according to expanding the global transport network, the international cooperation shall be strengthened, and the network infrastructure shall be secured. As for the strengthening methods of aviation logistics competitiveness of Incheon Airport, the enterprises' demand of moving in the logistics complex shall be responded, and the comparative advantage in the field of new growth cargo shall be preoccupied, and the logistics hub's capability shall be strengthened, and the competitiveness of cargo processing speed in the airport shall be advanced. Forth, in the subsequent negotiation of Korea-China FTA, the further opening of air transport services sector shall be secured. In the subsequent negotiation being initiated within two years after entry into force of Korea-China FTA, it is necessary to ask for the further opening of the concessions of computer reservation system services, and aircraft repair and maintenance services in which the concessions level of air transport services sector by China is insufficient compared to the concessions level in the existing FTA concluded by China. In conclusion, in order to respond to the impact on Korea's air passenger market, air cargo market and aviation logistics market by Korea-China FTA, the following policy tasks shall be pushed ahead : Taking into consideration of national air carriers' competitiveness and nation's benefits, the gradual and selective open skies shall be pushed ahead, and the support system to strengthen the competitiveness of air transport industry and airport shall be built, and entry into aviation logistics market by logistics enterprises shall be expanded, and the preparations to ask for the further opening of air transport services sector, low in the concessions level by China shall be made.

• Korean Journal of Remote Sensing
• /
• v.37 no.5_2
• /
• pp.1245-1257
• /
• 2021

GOCI-II, succeeding the mission of GOCI, was launched in February 2020 and has been in regular operation since October 2020. Korea Institute of Ocean Science and Technology (KIOST) processes and produces in real time Level-1B and 26 Level-2 outputs, which then are provided by Korea Hydrographic and Oceanographic Agency (KHOA). We introduced current status of regular GOCI-II operation and showed future improvement. Basic GOCI-II products including chlorophyll-a, total suspended materials, and colored dissolved organic matter concentration, are induced by OC4 and YOC algorithms, which were described in detail. For the full disk (FD), imaging schedule was established considering solar zenith angle and sun glint during the in-orbital test, but improved by further considering satellite zenith angle. The number of slots satisfying the condition 'Best Ocean' significantly increased from 15 to 78. GOCI-II calibration requirements were presented based on that by European Space Agency (ESA) and candidate fixed locations for calibrating local observation area were. The quality management of FD uses research ships and overseas bases of KIOST, but it is necessary to establish an international calibration/validation network. These results are expected to enhance the understanding of users for output processing and help establish detailed plans for future quality management tasks.