• Journal of Korean Society of Transportation
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• v.29 no.5
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• pp.121-138
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• 2011

More affordable and available cutting-edge technologies (e.g., wireless vehicle communication) are regarded as a possible alternative to the fixed infrastructure-based traffic information system requiring the expensive infrastructure investments and mostly implemented in the uninterrupted freeway network with limited spatial system expansion. This paper develops an advanced decentralized traveler information System (ATIS) using vehicle-to-vehicle (V2V) communication system whose performance (drivers' travel time savings) are enhanced by three complementary functions (autonomous automatic incident detection algorithm, reliable sample size function, and driver behavior model) and evaluates it in the typical $6{\times}6$ urban grid network with non-recurrent traffic state (traffic incident) with the varying key parameters (traffic flow, communication radio range, and penetration ratio), employing the off-the-shelf microscopic simulation model (VISSIM) under the ideal vehicle communication environment. Simulation outputs indicate that as the three key parameters are increased more participating vehicles are involved for traffic data propagation in the less communication groups at the faster data dissemination speed. Also, participating vehicles saved their travel time by dynamically updating the up-to-date traffic states and searching for the new route. Focusing on the travel time difference of (instant) re-routing vehicles, lower traffic flow cases saved more time than higher traffic flow ones. This is because a relatively small number of vehicles in 300vph case re-route during the most system-efficient time period (the early time of the traffic incident) but more vehicles in 514vph case re-route during less system-efficient time period, even after the incident is resolved. Also, normally re-routings on the network-entering links saved more travel time than any other places inside the network except the case where the direct effect of traffic incident triggers vehicle re-routings during the effective incident time period and the location and direction of the incident link determines the spatial distribution of re-routing vehicles.

• Journal of KIISE:Databases
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• v.30 no.3
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• pp.296-309
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• 2003

One of commercial applications of mobile computing is ATIS(Advanced Traveler Information Systems) in ITS(Intelligent Transport Systems). In ATIS, a primary mobile computing task is to compute the shortest path from the current location to the destination. In this paper, we have studied the shortest path re-computation problem that arises in the DRGS(Dynamic Route Guidance System) in ATIS where the cost of topological digital road map is frequently updated as traffic condition changes dynamically. Previously suggested methods either re-compute the shortest path from scratch or re-compute the shortest path just between the two end nodes of the edge where the cost change occurs. However, these methods we trivial in that they do not intelligently utilize the previously computed shortest path information. In this paper, we propose an efficient approximate shortest path re-computation method based on the dynamic window scheme. The proposed method re-computes an approximate shortest path very quickly by utilizing the previously computed shortest path information. We first show the theoretical analysis of our methods and then present an in-depth experimental performance analysis by implementing it on grid graphs as well as a real digital road map.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3D
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• pp.409-416
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• 2006

Real-time traveler information disseminated through Variable Message Signs (VMS) is known to have effects on driver route choice decisions. In the past, many studies have attempted to optimize the system performance using VMS message content as the primary control variable of driver route choice. This research proposes a VMS information provision optimization model which searches the best combination of VMS message contents and display sequence to minimize the total travel time on a highway network considered. The driver route choice models under VMS information provision are developed using a stated preference (SP) survey data in order to realistically capture driver response behavior. The genetic algorithm (GA) is used to find the optimal VMS information provision strategies which consists of the VMS message contents and the sequence of message display. In the process of the GA module, the system performance is measured using micro traffic simulation. The experiment results highlight the capability of the proposed model to search the optimal solution in an efficient way. The results show that the traveler information conveyed via VMS can reduce the total travel time on a highway network. They also suggest that as the frequency of VMS message update gets shorter, a smaller number of VMS message contents performs better to reduce the total travel time, all other things being equal.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.3
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• pp.149-156
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• 2020

The study aims to investigate a close relation between macro and non-macro variables on stock performance of tourism companies in Korea. The sample used in this study includes monthly data from January 2001 to December 2018. The stock price index of the tourism companies as a dependent variable are obtained from Sejoong, HanaTour, and RedcapTour as three leading Korean tourism companies that have been listed on the Korea Stock Exchange. This study assesses the tourism stock performance using the quantile regression approach. This study also investigates whether global crisis events as the Iraq War and the global financial crisis as non-macro variables have a significant effect on the stock performance of tourism companies in Korea. The results show that the oil prices, exchange rate and industrial production have negative coefficients on stock prices of tourism companies, while the effects of tourist expenditure and consumer price index are positive and significant. We estimate the result of quantile regression that non-macro determinants have statistically a significant and negative effect on tourism stock performance because the global crisis could threaten traveler's safety and economy. Overall, empirical results suggest that the effects of macro and non-macro variables are statistically asymmetric and highly related to tourism stock performance.

• Journal of the Korean Society of Food Culture
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• v.30 no.4
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• pp.413-421
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• 2015

A travel destination offers a form of novelty to the traveler since it can provide experiences that are not of the everyday variety. Therefore, a search for novelty is important as a motivation factor when planning leisure trips and vacation activities and to identify travel market segments. This study aimed to examine the differences in demographic characteristics, travel style, and preferred food-related activities in accordance with the level of tourists' novelty seeking. This study investigated potential tourists using a self-administered questionnaire survey, which resulted in 300 usable questionnaires. The respondents of this study were classified into two groups according to their level of novelty seeking: Active novelty-seeking group and Passive novelty-seeking group. These two groups were significantly different with respect to demographic characteristics, travel style, and preference of food-related-activity experience. The results show that the Active novelty-seeking group tended to have a higher proportion of females and specialized jobs, a higher level of monthly income and education, more frequent travel, and preference for food-related activity experience than other groups. The result of this study will be helpful for the tourist industry, which needs to develop culinary and food-related experience tour programs and travel market segments.

• Journal of the Korean Society of Food Culture
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• v.31 no.5
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• pp.381-399
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• 2016

The study presented attempts to analyze and categorize Chosun's food ingredients and culture through a Western perspective based on 32 representative Western documents pertaining to old Korea. Before modernization, Westerners visited Chosun during their visits to old China or Japan. Westerners were most active in Chosun from the open port period to the annexation of Korea to Japan occupation. They were teachers, missionaries, diplomats, and doctors visiting Chosun with personal goals. In 31 book traveler's journal, it records Chosen's mainly produced ingredients, such as grains, spices, fruits, cabbage, chicken, and chestnuts; foods from Chosen include kimchi, soup, and tofu. Foreigners especially liked foods made of eggs and chicken, but they did not enjoy Chosun's lack of sugar and dairy. Thirty-one book foreigners' records describe Chosun's Ondol, kitchen, crock, fermented foods, low dining tables, and chopsticks. Chosun people liked dog meat, unrestrained drinking culture, sungnyung, and tea culture. Foreign documentation on Chosun's food culture allows modern scholars to learn about Chosun people's lifestyles, as if their lives were a vivid picture.

• Parasites, Hosts and Diseases
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• v.58 no.1
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• pp.51-55
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• 2020

A 23-year-old Korean woman with a residence history in Kenya and Malawi for about 2 years presented with gross hematuria for 1 month. Blood tests were within normal range except eosinophilia. Asymmetrically diffuse wall thickening and calcification were observed at the urinary bladder on CT. Multiple erythematous nodular lesions were observed in the cystoscopy and transurethral resection was done. Numerous eggs of Schistosoma haematobium with granulomatous inflammation were observed in the submucosal layer of the bladder. The patient was diagnosed with schistosomiasis-related cystitis and treated with praziquantel (40 mg/kg/day) twice before and after transurethral resection. This case suggests that S. haematobium infection should be considered as a cause of hematuria in Korea when the patient had a history of traveling endemic areas of schistosomiasis.

• Journal of Korean Medical Science
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• v.33 no.53
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• pp.348.1-348.6
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• 2018

We report a case of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in a 61-year-old businessman returning from Kuwait. The patient arrived there on August 16, 2018, developed watery diarrhea on August 28 (day 0), and came back to Korea on September 7 (day 10) as his condition worsened. Upon arrival, he complained of diarrhea and weakness, but denied any respiratory symptoms, and he directly went to visit an emergency room. Chest radiography revealed interstitial infiltrates in the lungs, and he was immediately transferred to an isolation unit. Quantitative real-time PCR analysis of sputum samples taken on day 11 returned positive for MERS-CoV. No secondary MERS-CoV infection was identified among people who had close contact with him. This case underscores the importance of a high index of suspicion of MERS-CoV infection in any febrile patients who present after a trip to the Middle East.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.218-223
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• 1999

This paper introduces TIGS(Touring Information Guidance System) which provides information of the southwestern area of korea with faster access time than the human service. This system is designed specifically for a traveler. This TIGS provides tourists the informations such as destination, current map information, touring courses according to schedules, traffic information and lodging information. furthermore, this system is implemented with touchscreen for the user to apply easily. The shortest path algorithm is applied to schedule the touring courses to refute the time and the cost. The map is raster manner to represent southwestern area of korea instead of vectorial manner. If this developed system should be established in the public space such as station, airport, and bus station, touring will be more comfortable, the total income will more increase. Also, this system can be easily applied to different local area.

• Parasites, Hosts and Diseases
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• v.56 no.3
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• pp.215-227
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• 2018

Along with globalization of traveling and trading, fish-borne nematodiases seems to be increasing in number. However, apart from occasional and sporadic case reports or mini-reviews of particular diseases in particular countries, an overview of fish-borne nematodiasis among travelers have never been performed. In this review, we gathered fish-borne nematodiasis among travelers for recent 25 years by an extensive global literature survey using appropriate keywords, e.g. travelers diseases, human infection, anisakiasis, gnathostomiasis, capillariasis, sushi, sashimi, ceviche, Gnathostoma, Pseudoterranova, Anisakis, Capillaria, etc., as well as various combinations of these key words. The Internet search engines PubMed, Medline, Google and Googler Scholar were used as much as possible, and the references of every paper were checked in order to identify useful and reliable publications. The results showed unexpectedly high incidence of gnathostomiasis and low incidence of anisakidosis. The different incidence values of the infection with several fish-borne zoonotic nematode species are discussed, as well as some epidemiological aspects of the infections. The difficulties of differential diagnosis in non-endemic countries are emphasized. It is concluded that travelers must avoid risky behaviors which can lead to infection and that physicians and health authorities must advice travelers on the risks of eating behaviors during travel.