• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.26
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• pp.143-172
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• 2005

The biggest exchange of international environment of shipping logistics in 21 century should appear ultra-mega container ships on the shipping market. The competitive trend of large size container ship was based on economics of scale among the international shipping business. In the environment, shipping firms consider the integration of freight forwarder and shipper in the international logistics process. The aims of this research analyse a relation between the environment uncertainty and logistics information system(LIS) and the integration and resolve the integration and its impact on logistics performance. The research methodology of this research analyse structural equation modeling on the relation of variables. The results of research are as follows. First, Environmental uncertainty significantly influences the internal integration and the external integration. Second, LIS has an influence on the logistics integration by providing the foundation for LIS utilization in international logistics process. Third, the internal integration significantly influences a logistics performance, which implies that firms should promote interaction and collaboration through internal process integration to achieve logistics performance as the logistical cost and service. But the external integration is not significantly a logistics performance.

• Journal of Korean Institute of Industrial Engineers
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• v.37 no.4
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• pp.311-322
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• 2011

The core of this research studies the strategic alliance of airlines, container shipping liners, and port operators that have shown successful results through the recent differentiated strategic Alliance Network, although a difference of scale exists between these firms and the small and mid-sized International Logistics firms, but because of the worldwide traditional Alliance Network of International Logistics firms, HTFN's(High Tech Forwarder Network) half hearted attitude and the small scale alliance of the small and mid-sized International Logistics firms organized in 1998 cannot breakthrough the present strenuous situation. And these results, creating an attempt to save our country's International Logistics Industry which have fallen into depression, suggests an awakening of a new strategy based on specialized nationals innovative IT-which does not exist in the world market-by categorizing our country's small and mid-sized International Logistics firms which are active worldwide.

• Journal of Navigation and Port Research
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• v.31 no.5 s.121
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• pp.395-401
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• 2007

Recently, the government of Russia has been cooperating with developed countries such as Germany, which have an advanced railroad system. They have been establishing a strategy to activate the Siberia Trans Railway. Thus, it is possible that a part of cargo will be transported by TSR (Trans Siberia Railway) instead of shipping. If there is a railroad system, connecting the North and the South Korea via the Busan port, a new freight route linking to Europe will be reached. This paper aim to investigate the intention of shipping companies, shipper, forwarders, who are prospective customers and/or competitors of TSR. An analysis of the competitiveness between TSR system and the waterway transportation will be also mentioned.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.3
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• pp.919-940
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• 2012

Video on Demand (VOD) is a multimedia service which allows a remote user to select and then view video at his convenience at any time he wants, which makes the VOD become an important technology for many applications. Numerous periodic VOD broadcasting protocols have been proposed to support a large number of receivers. Broadcasting is an efficient transmission scheme to provide on-demand service for very popular movies. This paper proposes a new broadcasting scheme called Popularity Cushion Staggered Broadcasting (PCSB). The proposed scheme improves the Periodic Broadcasting (PB) protocols in the latest mobile VOD system, which is called MobiVoD system. It also, reduces the maximum waiting time of the mobile node, by partitioning the $1^{st}$ segment of the whole video and storing it in the Local Media Forwarder (LMF) exactly in the Pool of RAM (PoR), and then transmitting them when the mobile nodes miss the $1^{st}$ broadcasted segment. The results show that the PCSB is more efficient and better than the all types of broadcasting and caching techniques in the MobiVoD system. Furthermore, these results exhibits that system performance is stable under high dynamics of the system and the viewer's waiting time are less than the previous system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.5
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• pp.2144-2165
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• 2016

In a vehicular ad hoc network, the communication links are unsteady due to the rapidly changing topology, high mobility and traffic density in the urban environment. Most of the existing geographical routing protocols rely on the continuous transmission of beacon messages to update the neighbors' presence, leading to network congestion. Source-based approaches have been proven to be inefficient in the inherently unstable network. To this end, we propose an opportunistic beaconless packet forwarding approach based on a modified handshake mechanism for the urban vehicular environment. The protocol acts differently between intersections and at the intersection to find the next forwarder node toward the destination. The modified handshake mechanism contains link quality, forward progress and directional greedy metrics to determine the best relay node in the network. After designing the protocol, we compared its performance with existing routing protocols. The simulation results show the superior performance of the proposed protocol in terms of packet delay and data delivery ratio in realistic wireless channel conditions.

• ETRI Journal
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• v.37 no.3
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• pp.480-490
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• 2015

The reliability of sensor networks is generally dependent on the battery power of the sensor nodes that it employs; hence it is crucial for the sensor nodes to efficiently use their battery resources. This research paper presents a method to increase the reliability of sensor nodes by constructing a connected dominating tree (CDT), which is a subnetwork of wireless sensor networks. It detects the minimum number of dominatees, dominators, forwarder sensor nodes, and aggregates, as well as transmitting data to the sink. A new medium access control (MAC) protocol, called Homogenous Quorum-Based Medium Access Control (HQMAC), is also introduced, which is an adaptive, homogenous, asynchronous quorum-based MAC protocol. In this protocol, certain sensor nodes belonging to a network will be allowed to tune their wake-up and sleep intervals, based on their own traffic load. A new quorum system, named BiQuorum, is used by HQMAC to provide a low duty cycle, low network sensibility, and a high number of rendezvous points when compared with other quorum systems such as grid and dygrid. Both the theoretical results and the simulation results proved that the proposed HQMAC (when applied to a CDT) facilitates low transmission latency, high delivery ratio, and low energy consumption, thus extending the lifetime of the network it serves.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.04a
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• pp.158-159
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• 2011

Energy efficiency in wireless sensor networks (WSNs) is one significant factor that needs to be considered when making any designs or doing any enhancements on the communication protocol stack. In WSNs using traditional geographic routing, when a sensor node receives a data packet that needs to be transmitted to the sink, it will forward the packet to the neighbor node which is closest to the sink. The traditional geographic routing assumes that the link quality is always 100%. This may cause a bad result as per which we waste too many energy for retransmissions between the two nodes. Thus, the problem here is how to select such node as forwarder at most efficiently in the aspect of both energy consumption and the distance toward the destination. The better node we choose, the more energy we can conserve for the whole network. In this paper, we propose a next-hop forwarding selection metric, called Energy Consumption for Transmission (ECT), which can resolve the above problem in the best way.

• 한국벤처창업학회:학술대회논문집
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• 2021.04a
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• pp.165-170
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• 2021

최근의 코로나19 사태로 관광·항공업계가 극심한 어려움을 겪고 있다. 항공업계의 대안 중 하나는 화물운송이다. 항공사들은 여객수요 급감으로 인한 매출감소 폭을 줄이기 위하여 화물운송 부문을 강화하고 있다. 항공화물운송은 타 운송과 구분되는 제반 특성으로 인하여 시장규모가 지속적으로 증가하고 있다. 항공화물운송 대리점(forwarder)은 수출과 수입에 있어서 중요한 역할을 담당하며, 중요한 비즈니스 파트너인 항공사와 수출입자와 우호적인 긴밀한 관계를 구축하고 계속 유지해야 한다. 사회적 교환이론(social exchange theory)은 이러한 관계가 구축되기 위해서는 거래당사자 간의 거래규모나 거래기간, 거래빈도 등의 유형적인 측면도 중요하지만, 신뢰와 몰입, 애착 등의 무형적인 측면의 교환이 선행되어야 한다는 것을 강조한다. 본 연구의 연구목적은 다음과 같다. 첫째, 물류서비스기업의 업무 프로세스를 규명하고 운송기업 및 화주기업과의 사회적 교환행동은 어떻게 이루어지는지 조사한다. 둘째, 이러한 사회적 교환행동이 물류서비스기업의 다양한 경영성과에 얼마나 영향을 미치는지를 분석한다. 셋째, 각 구성원 간의 관계기간에 따라서 이러한 영향력이 달라지는지를 살펴본다. 특히 본 연구는 많은 기존연구에서 구분되었던 신뢰(trust)와 몰입(commitment) 개념을 통합함으로써 연구모형의 간결성(parsimony)과 실용가능성(practicality)을 제고하고자 한다. 결과적으로 본 연구는 운송기업 및 화주기업에 대한 물류서비스기업의 사회적 행동이 신뢰에 기반한 우호적인 관계를 구축하는지, 경영성과에는 어떤 영향을 미치는지를 실증적으로 살펴보고, 관계기간의 조절효과를 규명함으로써 학문적으로나 실무적으로 유용한 시사점을 제공할 수 있으며, 창업 물류서비스기업에 유용한 가이드라인을 제시할 수 있을 것이다.

• Korea Trade Review
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• v.46 no.1
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• pp.135-154
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• 2021

This study aims to investigate the difference in the perception of shippers on the quality of air freight service between air express and air freight forwarders. This study suggests hypothesis verification and implications on importance-performance between two groups of air express and air freight forwarders. In this study, we find that important variables through paired t-test and importance-performance analysis. As a result of paired t-test, there was a difference in the use variables of the document work variables through computerization in the importance area. In the satisfaction area, there was a difference between the groups in the response to customer request and the response to accidents. The variables that need to improve the focus derived from the importance-performance analysis are document work through computer and response to accidents. It is necessary to observe and manage the response of shippers continuously by holding various transportation schedules in the schedule area, possibility of adjustment of transportation schedule, regular freight and schedule provision.

• Journal of Navigation and Port Research
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• v.32 no.1
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• pp.97-102
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• 2008

According to the trend of a large-sized vessel and a industrial carrier, the role of the independent contractors such as transport terminal operators, stevedores and warehousemen is increasing the base of cargo distribution that include the function of storage, warehousing, loading, unloading, trimming, dunnaging and lashing. But the common law doctrine of privity of contract has been a perennial source of difficulty for litigants seeking to enforce rights and obligations arising under a bill of lading contract. When carriage contract is negotiated, the concerned parties will be aware that some portion of obligations arising from the contract will be performed by the independent contractors engaged to carry out a particular function. It is reasonable for the independent contractors to be allowed the benefit of the carrier under the contract of carriage. As a part of the alleviating measures for the liability of independent contractors has been allowed various schemes, specially including 'Himalaya Clause'. Therefore, this study performed the validity of 'Himalaya Clause' by means of a recent judicial precedent by the Supreme Court and analyzed the rights of third parties, specially transport terminal operators, under the contract of carriage.