• International Journal of Fuzzy Logic and Intelligent Systems
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• 제14권4호
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• pp.288-294
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• 2014

Understanding a ship's present position has been one of the most important tasks during a ship's voyage, in both ancient and modern times. Particularly, a ship's dead reckoning (DR) has been used for predicting traffic situations and collision avoidance actions. However, the current system that uses the traditional method of calculating DR employs the received position and speed data only. Therefore, it is not applicable for predicting navigation within the harbor limits, owing to the frequent changes in the ship's course and speed in this region. In this study, planned routes were applied for improving the reliability of the proposed system and predicting the traffic patterns in advance. The proposed method of determining the dead reckoning position (DRP) uses not only the ships' received data but also the navigational patterns and tracking data in harbor limits. The Mercator sailing formulas were used for calculating the ships' DRPs and planned routes. The data on the traffic patterns were collected from the automatic identification system and analyzed using MATLAB. Two randomly chosen ships were analyzed for simulating their tracks and comparing the DR method during the timeframes of the ships' movement. The proposed method of calculating DR, combined with the information on planned routes and DRPs, is expected to contribute towards improving the decision-making abilities of operators.

• 한국정보과학회논문지:정보통신
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• 제29권1호
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• pp.48-56
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• 2002

본 연구는 IP(Internet Protocol) 망에서 복수 트리경로에 의한 멀티캐스팅 방법을 제시한다. 트래픽 양에 대해 아크 비용이 비선형 함수이고 멀티캐스트 트래픽 수요가 대용량일 때, 단일의 트리경로 대신에 트래픽을 분할하여 복수개의 트리경로로 전송하는 것이 멀티캐스트 서비스 품질을 향상시킬 수 있다. 제시하는 멀티캐스팅 방법은 원하는 수준까지 트리경로를 추가하며, 주어진 트리경로 집합에 대해서 트래픽을 분할한다. 트래픽 분할을 위한 수학적 모형과 최적조건을 도출하였으며, 여러 개의 멀티캐스팅 트래픽을 동시에 전송하고자 할 때도 적용 가능하다. 적용 결과는 제안한 복수 트리경로에 의한 IP 멀티캐스팅 방법이 단-대-단 서비스 품질을 보장하는 데도 상당한 효과를 있음을 보인다.

• 한국농공학회논문집
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• 제46권1호
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• pp.121-131
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• 2004

Transportation and logistics of agricultural products have been one of the major interests of many researches. Most of researches have been limited to presuming these as a first dimensional process or considering only economic value of agricultural products at each stage of logistics. However, the particular characteristics of agricultural products, such as quality change during transportation or extensively scattered origins, require examining these problems as a whole system. Network model has been adopted to represent nodes, which stand for spatial location of demand and supply of agricultural products, and communication between these nodes. Based on network theory and advanced marketing potential function, an optimal routes selection model is developed. The model employed network simplex method for routes optimization. The application of the model focused on transportation network organization to reflect different market prices for different locations and resulted in optimum routes and profit improvement of the applied agricultural product.

• Acta Via Serica
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• 제3권2호
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• pp.23-48
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• 2018

The Silk Road usually implies a network of trade and communications that stretched from east to west and connected China and the countries of the Far East via Central Asia and the Middle East to the eastern Mediterranean, or through the northern coast of the Caspian Sea and the Volga basin to the Black Sea coast. However, at certain historical stages, a network of maritime and overland routes stretching from north to south, commonly called the Volga-Caspian trade route, also played a significant role in international trade and cultural contacts. The geopolitical realities of the early Middle Ages relating to the relationship of Byzantium, the Sassanid Empire, and the West Turkic Khaganate, the advance of the Arab Caliphate to the north, the spread of Islam in the Volga region, the glories and fall of the Khazar State, and the Scandinavian campaigns in the Caucasus, closely intertwined with the history of transport and communications connecting the north and south through the Volga-Caspian route. In a later era, the interests of the Mongolian Uluses, and then the political and economic aspirations of the Ottoman Empire, the Safavid State, and Russia, collided or combined on these routes. The article discusses trade contacts existing between the north and the south in the 15th and first half of the 17th century along the routes on the western coast of the Caspian Sea.

• 한국분무공학회지
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• 제24권2호
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• pp.73-81
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• 2019

It is expected that the introduction of real-driving emission will strengthen the exhaust emission. However, various researches have been reported that real-driving emission has been influenced by factors such as characteristics of the test routes and driving characteristics for drivers. In order to reflect this effect, European Commission applied the concept of driving dynamics to prevent deliberately driving of excessive and acceleration over RDE test. The purpose of this study is to analyze the characteristics of exhaust emissions according to real-driving test in three test routes and driving style. As a result of the test, it was confirmed that when the same driver tested real-driving test under three test routes, it depends on the driving characteristics of the route. Also, RDE-NOx for driving style was that severe driving has been about 16 times higher than normal driving in KNUT route.

• Journal of Korea Trade
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• 제27권3호
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• pp.119-146
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• 2023

Purpose - As the severity of air pollution caused by the shipping industry is becoming evident, port authorities have started making efforts to reduce air pollutants. Considering the limitations of the currently implemented emission-control area (ECA) and vessel-speed reduction program (VSRP), which are narrow in the designation range and navigation behavior of ships, this study proposes an emission-control route (ECR) that can complement the aforementioned two environmental policies. Design/methodology - This study was conducted on Korea-China trade service routes (ports of call) of regular liners. This study employed vessel-specific data, which is from an automatic identification system (AIS), for 1,728 maritime transportations performed by 387 container vessels during one year (July 1, 2021, to June 30, 2022). Performing a scenario analysis, this study analyzed the effectiveness of reduced air-pollutant emissions. Findings - This study found that the implementation of ECRs could increase average voyage time by 12.38%-25.28% but reduced air-pollutant emissions by 29.02%-43.54%. Additionally, the increase in average voyage times reduces the anchorage time of ships outside ports, providing an incentive for ship operators to voluntarily participate in compliance with regulations, thereby contributing to the establishment of a virtuous cycle of air-environmental policies related to ships. Originality/value - This study aims to verify the policy effectiveness by designing an ECR scope for liner trade routes between Korea and China. Therefore, originality and the value of this study includes conceptualizing the ECR system, analyzing its environmental performance, and exploring new policies that can be implemented while complementing existing policies.

• 대한교통학회지
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• 제25권6호
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• pp.43-53
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• 2007

기존의 소방도로는 법적 용어가 아닌 편의상 지칭하는 명칭으로 도로교통법이나 지방경찰청장 고시 등에 의한 주 정차 단속구간이 아니다. 이러한 이유로 화재 등 긴급 상황 발생시 소방차량의 현장접근이 늦어져 재산 및 인명 피해가 확대되는 일이 빈번히 발생하고 있다. 본 연구에서는 기존의 애매했던 소방통로의 개념을 보완하고 새롭게 소방통로의 개념을 정립하고자 새로운 용어인 방재경로라는 개념을 도입하였다. 소방차량의 제원 및 지역 특성을 고려한 방재경로 선정기법을 제안하고, 효과적인 운영을 위한 법적 근거 및 지속적인 관리/감독을 위한 전담 관리 부서를 제안하였으며, 서울시 한개 동을 대상으로 한 화재발생 가상시나리오에서는 방재경로를 통한 소방차의 신속한 접근으로 피해가 감소될 수 있는 것으로 나타났다. 방재경로 확보는 각종 재난으로부터 시민을 보다 신속하고 안전하게 보호하기 위한 방안으로서 화재 등 긴급 상황 시 시민의 안전 확보뿐만 아니라, 해당 도로의 주 정차 금지로 인한 도로의 혼잡완화로 향후 시민의 큰 호응을 얻을 수 있을 것으로 판단된다.

• 한국의상디자인학회지
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• 제12권3호
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• pp.1-15
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• 2010

The purpose of this study is to clarify of the distribution routes of cosmetics by their types and differences in choosing them according to ages with the ones in choosing brand by the type according to them. The subjects of the study were females aged 20 plus living in Seoul and Gyeonggi Province between January and February 2008, and 427 questionnaires were used for analysis. For data analysis SPSS 17.0 statistical program was used, and principal component analysis, frequency analysis, ${\chi}^2-test$, ANOVA test and Duncan test were conducted. The results and conclusions of this study are as follows: first, cosmetics store use by product type was examined. Department stores were used most often to purchase skincare, base and color products, while large cosmetics stores were used most frequently to buy hair and body products. Second, The result of the differences in choosing brand by type of cosmetics has found that there are the meaningful differences between Korean low and middle priced brands and foreign high priced ones in skincare and base products. The Korean low and middle priced brands of skin care products show that various distribution routes are simultaneously and highly used as choices in internet, cosmetics specialty stores and large general ones are higher than other distribution routes. Color products have found that there are the meaningful differences in the entire brands. Hair and body products have found that there are the meaningful differences in three brands except the Korean high priced brands. Third, the differences in cosmetics store selection by age were investigated. As for online purchasing, people in their 20's were most likely than other age groups to purchase online. Meanwhile, in case of other stores including door-to-door sales and home shopping, people aged 40 and older were more prone than other age groups to purchase base, color and body products through these stores.

• 한국ITS학회 논문지
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• 제4권1호
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• pp.1-13
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• 2005

다양한 대중교통수단이 함께 구축되어 있는 통합대중교통망(Integrated Transit Network)에 대하여, 최적통행시간 경로정보뿐만 아니라 다수의 최적통행시간 정보를 제공하는 방안에 대한 기초연구는 그 사례를 찾아보기 어렵다. 본 연구는 다수의 대중교통경로를 탐색하기 위하여, 버스와 지하철의 두 수단이 함께 존재하는 복합교통망에서 K개의 최소통행시간을 갖는 경로를 탐색하는 방안을 제안한다 제안된 방안은 통행정보에서 대중교통 사용자가 일반적으로 필요로 하는 다음의 3가지 제약조건 (1) 수단의 서비스시간제약, (2) 통합거리비례제 요금제약, 3) 환승회수제약을 고려한다. 사례연구를 통해 K개의 최소통행시간 경로정보뿐만 아니라 위의 제약조건을 조합적으로 반영하여 사용자에게 필요한 경로정보의 질적 향상 및 다양화에 대한 가능성을 제시한다.

• 한국산학기술학회논문지
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• 제14권11호
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• pp.5885-5889
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• 2013

일반적으로 서바이벌 특성이란 네트워크 장애 시 고객이 인식하기 전에 서비스가 복구 될 수 있는 것을 말한다. 예를 들면 데이터 전송 중에 링크장애가 발생하면 즉시 대체 경로를 찾아 데이터 전송이 중단되지 않도록 하는 것이다. 이때 이용되는 것이 이중경로를 찾는 알고리즘이고 이때 주요요소가 경로 비용이 된다. 한 노드에서 다른 노드로 데이터 전송을 할 때 최소비용경로를 찾는 것이 효율적이다. 이때 찾아진 최소비용경로는 네트워크 장애가 발생하지 않는 경우에는 최적의 경로가 될 수 있다. 다만 네트워크 장애가 발생한 경우 대체 경로를 찾아야 하는데 이때 대체 경로의 비용이 매우 높다고 하면 비용 면에서 비효율적일 수 있다. 따라서 본 논문에서는 네트워크 설계 시 서바이벌 특성을 고려하여 최소비용을 갖는 이중경로가 각각의 두 노드 사이에 최대한 존재 할 수 있는 방법을 찾는다.