• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.395-400
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• 2006

Among the various error sources in positioning and navigation, the paper focuses on the modeling and prediction of receiver clock bias and then tries to achieve positioning based on simulated and predicted clock bias. With the SA off, it is possible to model receiver clock bias more accurately. We selected several types of GNSS receivers for test using ARMA model. To facilitate prediction with short and limited sample pseudorange observations, AR and ARMA are compared, and the improved AR model is presented to model and predict receiver clock bias based on previous solutions. Our work extends to clock bias prediction and positioning based on predicted clock bias using only 3 satellites that is usually the case under urban canyon situation. In contrast to previous experiences, we find that a receiver clock bias can be well modeled using adopted ARMA model. Test has been done on various types of GNSS receivers to show the validation of developed model. To further develop this work, we compare solution conditions in terms of DOP values when point positioning is conducted using 3 satellites to simulate urban positioning environment. When condition allows, height component is derived from other ways and can be set as known values. Given this condition, location is possible using less than 2 GNSS satellites with fixed height. Solution condition is also discussed for this background using mode of constrained positioning. We finally suggest an effective predictive time span based on our test exploration under varied conditions.

• Steel and Composite Structures
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• v.8 no.6
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• pp.457-473
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• 2008

Yielding of the internal steel reinforcement is an important mechanism that influences the Intermediate Crack-induced debonding (IC debonding) behavior in FRP-strengthened RC members since the FRP is required to carry additional forces beyond the condition of steel yielding. However, rational design practice dictates an appropriate limit state is defined when steel yielding is assured prior to FRP debonding. This paper proposes a criterion which correlates the occurrence of IC debonding to the formulation of a critical steel yielding length. Once this length is exceeded the average bond stress in the FRP/concrete interface exceeds its threshold value, which proves to correlate with the average bond resistance in an FRP/concrete joint under simple shear loading. This proposed IC debonding concept is based on traditional sections analysis which is conventionally applied in design practice. Hence complex bond stress-slip analyses are avoided. Furthermore, the proposed model incorporates not only the bond properties of FRP/concrete interface but also the beam geometry, and properties of steel and FRP reinforcement in the analysis of IC debonding strength. Based upon a solid database, the validity of the proposed simple IC debonding criterion is demonstrated.

• Journal of Daesoon Thought and the Religions of East Asia
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• v.2 no.1
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• pp.85-109
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• 2022

Yiguandao missions arrived in Korea no later than 1947. Despite many obstacles, including war and internal dissension, the movement has flourished in South Korea. Today there are three active major lineages and another seven smaller networks. This article relates the movement's overall development in Korea. We begin by discussing key missions dispatched to Korea by Yiguandao's founder Zhang Tianran. The northern port city of Tianjin was key to this effort, in particular a single temple, the Hall of Morality. In Korea the leaders found an unfamiliar cultural landscape that was soon engulfed in war. The Yiguandao missions tended to develop independently, without coordination. In an effort to unify the movement, the Morality Foundation was established in Busan in 1952. The article shows how Yiguandao's subsequent success in Korea is connected to the development of indigenous leadership. Local Korean leadership ousted Chinese members from the Morality Foundation in 1954, and this branch has continued under Korean leadership to this day. The ousted Chinese leaders continued to develop their own lineages. Two major leaders, Zhang Ruiquan and Kim Bokdang, were able to establish enduring legacies. A final section looks at organizational traits that will determine the movement's future prospects in modern Korean society.

• Korea Trade Review
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• v.41 no.3
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• pp.27-42
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• 2016

This study is to investigate seaport clustering by using meta-frontier and cross-efficiency models. Data covers the 13 Asian ports during 2009, 2010 and 2013 with 3 inputs(depth, total area, and number of cranes) and 1 output(TEU). Correlations coefficient from cross-efficiency matrix are used for measuring clustering dendrogram. After that, meta-frontier analysis for investigating whether the clustering using cross-efficiency method increases the meta-efficiency. Empirical main results are as follows: First, group efficiencies of Busan, Incheon, and Gwangyang ports are increased. Second, meta and group efficiencies of China ports are greater than those of Korean ports. Third, distortion of technology gap of Gwangyang is lower than that of Busan and Incheon. Fourth, Gwangyang, clustering with Ningbo, Chingtao, Tokyo and Caosung ports in 2009 and with Dubai port in 2013 can increase the efficiency. Fifth, to enhance the efficiency, Busan port should be clustered to group 2 in 2010 and group 1 in 2013, and Incheon port clustered to group 2 in 2010 and 2013. Fifth, it is empirically investigated that Busan, Incheon and Gwangyang ports can increase the efficiency by using Cross-efficiency and Meta-frontier models. Port policy planner should promote the clustering policy for Busan with Hong Kong, Shanghai, and Singapore, Incheon and Gwangyang with Chingtao, Nagoya, Ningbo, Tokyo, and Kaoshung ports.

• Journal of Korea Port Economic Association
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• v.37 no.1
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• pp.31-70
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• 2021

The purpose of this paper is to measure the clustering change and analyze empirical results, and choose the clustering ports for Busan, Incheon, and Gwangyang ports by using Hierarchical clustering(single, complete, average, and centroid), Silhouette, and 2SCE[the Second Stage(Type II) cross-efficiency] matrix clustering models on Asian container ports over the period 2009-2018. The models have chosen number of cranes, depth, birth length, and total area as inputs and container TEU as output. The main empirical results are as follows. First, ranking order according to the efficiency increasing ratio during the 10 years analysis shows Silhouette(0.4052 up), Hierarchical clustering(0.3097 up), and 2SCE(0.1057 up). Second, according to empirical verification of the Silhouette and 2SCE models, 3 Korean ports should be clustered with ports like Busan Port[ Dubai, Hong Kong, and Tanjung Priok], and Incheon Port and Gwangyang Port are required to cluster with most ports. Third, in terms of the ASEAN, it would be good to cluster like Busan (Singapore), Incheon Port (Tanjung Priok, Tanjung Perak, Manila, Tanjung Pelpas, Leam Chanbang, and Bangkok), and Gwangyang Port(Tanjung Priok, Tanjung Perak, Port Kang, Tanjung Pelpas, Leam Chanbang, and Bangkok). Third, Wilcoxon's signed-ranks test of models shows that all P values are significant at an average level of 0.852. It means that the average efficiency figures and ranking orders of the models are matched each other. The policy implication is that port policy makers and port operation managers should select benchmarking ports by introducing the models used in this study into the clustering of ports, compare and analyze the port development and operation plans of their ports, and introduce and implement the parts which required benchmarking quickly.

• Journal of Korea Port Economic Association
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• v.34 no.3
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• pp.17-52
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• 2018

The purpose of this paper is to measure the clustering change and analyze empirical results. Additionally, by using k-means, hierarchical, and mixed models on Asian container ports over the period 2006-2015, the study aims to form a cluster comprising Busan, Incheon, and Gwangyang ports. The models consider the number of cranes, depth, birth length, and total area as inputs and container twenty-foot equivalent units(TEU) as output. Following are the main empirical results. First, ranking order according to the increasing ratio during the 10 years analysis shows that the value for average linkage(AL), mixed ward, rule of thumb(RT)& elbow, ward, and mixed AL are 42.04% up, 35.01% up, 30.47%up, and 23.65% up, respectively. Second, according to the RT and elbow models, the three Korean ports can be clustered with Asian ports in the following manner: Busan Port(Hong Kong, Guangzhou, Qingdao, and Singapore), Incheon Port(Tokyo, Nagoya, Osaka, Manila, and Bangkok), and Gwangyang Port(Gungzhou, Ningbo, Qingdao, and Kasiung). Third, optimal clustering numbers are as follows: AL(6), Mixed Ward(5), RT&elbow(4), Ward(5), and Mixed AL(6). Fourth, empirical clustering results match with those of questionnaire-Busan Port(80%), Incheon Port(17%), and Gwangyang Port(50%). The policy implication is that related parties of Korean seaports should introduce port improvement plans like the benchmarking of clustered seaports.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.3
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• pp.407-418
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• 2011

The southern region including Guangzhou(黃州), the capital of Guangdong Province, was called "South of the Mountain Range" (嶺南) because it is located south of the Five Mountain Ranges (五嶺) which made mobility difficult prior to unification of China by Qin dynasty (秦) in 221 BCE. The Guangdong region of the South of the Mountain Range (嶺南) was an administratively independent unit and, as such, called the Nanyue kingdom (南越國). This is the origin of the Chinese character "yue", and terms such as yueyu (Cantonese), yuecai (Cantonese cuisine), yueju (Cantonese opera) are still in use today. Guangzhou, called Panyu (番禹) during the Nanyue kingdom period, was settled early in the northern part of the Pearl River (珠江, Zhu Jiang) delta. It became the first port to open its doors to the great powers of the West during the Qing period. Although it has now fallen behind Shanghai which developed later, Guangzhou is still the third largest city after Beijing and Shanghai, and thus, it is an influential open coastal city. Today, not only is Guangzhou the world center of the light textile industry, it also spurs development in various manufacturing industries. Along with nearby Hong Kong, Macao, and Shenzhen, it plays the role of cradle of the Pearl River delta economic zone. Firmly established early on as the greatest central city in southern China, Guangzhou is simultaneously a hub in various aspects such as regional politics, economics, and culture; it was also the center of revolution and resistance which attempted to challenge the northern political powers. Guangzhou is known for the history of the rise and fall of its port, but with developmental efforts, it still maintains its influence. Guangzhou's dynamic development of today brings with it issues such as the environment and moral system which must be dealt with.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5D
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• pp.739-747
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• 2011

The paper presents implementation & evaluation of survey method with tilted transducer of Multi Beam Echo Sounder (MBES) to increase horizontal & vertical coverage over obstructed port environments with limited physical properties of MBES. Proposed method ($25^{\circ}$ titled transducer) have some discrepancy of bathymetric profiles between normal and tilting method, but we proved average difference is less than IHO Special Order requirements with survey data at port of Dong Ho Port, Masan, Korea. For horizontal mapping coverage of total survey area ($114,961m^2$), normal method covered 53%, $60,895m^2$ of total area but tilting method covered 75%, $5.933m^2$. It is 22% efficient than normal method with similar environments. For vertical mapping coverage of total vertical structure face ($7,421m^2$), normal method covered 14%, $1,046m^2$, proposed methods covered 60%, $4,450m^2$. And we adapt longitudal steel bar to validate MBES results, and provide calibration method with titled transducer of MBES.

• Journal of architectural history
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• v.32 no.3
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• pp.7-20
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• 2023

The compositions of ethnic groups in Macau vary with time. Prior to the opening of the port, the majority of the residents in Macau were Chinese people, including those living on land and at sea. After the port was opened, with the increase of Portugal businessmen and missionaries, the population was divided into Chinese people and foreigners (so-called 'Yiren' or 夷人 in Chinese). Chinese people living on land were mainly of Hakka, Fujian, and Cantonese descent. Those living at sea were referred to as 'Tanka People' (named 'Danmin' or 蜑民in Chinese). They lived on floating boats for their entire lives and were similar to the 'drifters' in Japan. Since modern times, many refugees from mainland China and Southeast Asia flooded into Macau due to warfare. The development of industrialization required a larger number of laborers, and some 'coolies' entered Macau in legal or illegal ways, making it a multi-ethnic city. However, the Tanka people were not considered a minority ethnic group under the national ethnic policy of 56 ethnic groups since they did not have an exclusive language and shared dialects in different regions. As the ports inhabited by Tanka people gradually restored foreign trade, the boats and stilt houses used by Tanka people were dismantled to expand the infrastructure area of the ports. Many Tanka people began to live on land and marry people on land, leading to the disappearance of the Tanka group in Macau. The fishing boats and stilt houses used by Tanka people have also disappeared, with only a few remaining in areas such as Pearl River Delta and Hong Kong. This paper examines the natural and social environment of Tanka people in Macau from the Ming and Qing dynasties to the Republic of China, as well as the adaptive changes they adopted for the aforementioned environment in terms of living space and architectural type, on the basis of summarizing the historical activities of Tanka people. Finally, this study provides a layout plan and interior structure of the most commonly used boat for Tanka people from the Ming and Qing dynasties to the Republic of China, with the use of CAD and other technical software, along with reference to written historical documentation, and provides a case study for further research on the architectural history of Macau's inner harbor cities, from anthropological and folklore perspectives.

• Journal of the Korean Society of Marine Environment & Safety
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• v.6 no.2
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• pp.1-15
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• 2000

In world trade, the vessel traffic in major routes has been congested due to the rapid increase of cargoes and shipping tonnages. The patterns of vessel traffic have also been complicated and diversified. Therefore it was necessary that the Vessel Traffic Service(VTS) should be established in order to enhance the safety of navigation, to prevent the loss of life and damage to the environment. The first advanced radar surveillance system(LevelIII-VTS) was introduced in Pohang, Korea in 1993 and in 13 other ports later. While the hardware of Korea VTS is equal to that of an advanced country, the software, specially the operation manual, the recruitment and education of VTS operator, and the VTS service area is behind that of Russia, USA, Germany, Hong Kong, Singapore and others. After researching and investigating. the VTS equipment and service area of many countries, and analyzing the IMO regulations relevant to VTS and the traffic pattern and accident of Pohang port, the most efficient VTS service area should be established in Pohang. According to the analysis of the preceding studies and research on VTS, the worldwide VTS areas are recognized under the following conditions: First, the service area should be extended over at least radar coverage taking into account of traffic flow, traffic density, the degree of danger to navigation and harbour condition in order to provide all possible services. Second, the established service area should be subdivided and systematized to render reliable VTS services, such as the allocation of VHF frequency and reporting procedure in each area. In conclusion, the VTS service area of Pohang must be established and operated over 10 miles from shore(radar site) covering the radar coverage, so as to include the area of traffic congestion and high density traffic flow.