• Journal of the Korean Society of Marine Environment & Safety
• /
• v.25 no.3
• /
• pp.306-312
• /
• 2019

This paper investigates to design a controller for maritime autonomous surface ship (MASS) by means of adaptive super-twisting algorithm (ASTA). A input-out feedback linearization method is considered for multi-input multi-output (MIMO) system. Sliding Mode Controller (SMC) is suitable for MASS subject to ocean environments due to its robustness against parameter uncertainties and disturbances. However, conventional SMC has inherent disadvantages so-called, chattering phenomenon, which resulted from the high frequency of switching terms. Chattering may cause harmful failure of actuators such as propeller and rudder of ships. The main contribution of this work is to address an appropriate controller for MASS, simultaneously controls surge and yaw motion in severe step inputs. Proposed control mechanism well provides convergence bewildered by external disturbances in the middle of steady-state responses as well as chattering attenuation. Also, the adaptive algorithm is contributed to reducing non-overestimated value of control gains. Control inputs of surge and yaw motion are displayed by smoother curves without excessive control activities of actuators. Finally, no overshoot can be seen in transient responses.

• Journal of Distribution Science
• /
• v.19 no.8
• /
• pp.47-56
• /
• 2021

Purpose: Maritime sector is fundamental to international trade; there is no doubt that seafarers have played an essential role in maritime shipping and distribution science industry. Thus, this study uses Grey models to predict the number of seafarers in Vietnam expecting to provide a range of future seafarers. Research design, data and methodology: Statistics data are adopted for numbers of seafarers by Vietnam Maritime Administration categorizing into three types: Officers at Management level, Officers at Operational level and Navigation - Engine officer cadet. Results: The results have showed that a lack of qualified seafarers in the distribution industry, which has become a global issue and Vietnam is facing challenges of providing enough supply of seafarers in the next few years. Since there has been a concern of the unbalance between demand and supply of seafarers, researches in maritime sector needs a high accuracy in forecasting the number of available qualified seafarers in Vietnam. Conclusion: This method can be applied to predict numbers of other human resources in transportation, distribution and/or logistics industries when the information is poor and insufficient. The next few years are predicted to witness a downtrend in sailors - oilers which leads to the fact that the total number of available seafarers is decreased.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.12
• /
• pp.2511-2519
• /
• 2015

In maritime logistics, the technology for transmitting status information has been greatly developed, but it has not been available in general logistics environment or it is impossible to support two-way communication as it simply receives and transfers a container's information. In particular, to support two-way communication in all sections of the global maritime logistics, the address value, which can identify the tag, should be managed. In this context, to improve the 433 MHz-based RFID, the project called "DASH 7" has been conducted in recent years. However, it has stopped proceeding because of its slow progress, including the standardization and development of references. In this paper, we introduced an active IP-RFID system configuration for real-time communication in global maritime logistics using a two-way communication-which is characteristic of an IP-applying virtual address values in the RFID tag, and proposing its process and function. When you apply the IP-RFID system proposed in this paper, not only real-time status tracking in the maritime logistics area is possible, but it is also applicable for controlling the tag.

• Journal of Navigation and Port Research
• /
• v.30 no.6 s.112
• /
• pp.517-524
• /
• 2006

World ports and shipping markets are changing dynamically. The 9,000TEUs classed container vessels are avaiable to enter service now, so liner services are ready to start. With regard to the changing environment, the world ports ease regulations as well as invest funds to be leading ports. As a result, the importance of port logistics industry is getting bigger than before. It has an effect on improvement of service quality when a shipping company selects a port. The importance of tally, one cf the necessary elements in the port logistics industry is overlooked and there is no researches for tally yet. This paper suggests plans for the development of domestic tally after the investigations and analysis of survey are conducted.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.29 no.1
• /
• pp.345-352
• /
• 2005

Recently the large shipping companies are reducing a port of call to cut down on expenses related to the large size of ship for economy of scale. Due to this, it is necessary to work out a strategy to overcome the severe competition among ports. According to the importance of port marketing, there were many studies on port marketing. But previous studies for domestic port marketing are considered more importantly Products, Price and Promotion than Place of the 4Ps of marketing mix strategy. But it has to preferentially consider the place strategy in Busan Port because the best advantage is geographical position. So this paper shows the strategic plan of Place Marketing.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2006.06b
• /
• pp.405-410
• /
• 2006

World port and shipping market are changing dynamically, now 9,000TEU vessel made a maiden voyage and served liner service. So world ports try to occupy leading position and they are changing their regulations and law. Because port logistics industry's importance is bigger than before and when shipping companies select port, it is related with improvement of service quality. Tally is indispensable element in port logistics industry but overlooking its importance. Also, now we can't find any papers or reports about tally, so this paper suggests the direction that go forward about domestic tally guideline through present condition through investigation and question's analysis.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2016.05a
• /
• pp.58-58
• /
• 2016

This study aims to enhance Korea's competitiveness by taking the lead in the international standardization and relevant global market. This is to be achieved by performing the role of First Mover through the resolute investment from Fast Follower that is servile to the decision of the organization in the e-Navigation strategy that has been promoted by the IMO. The study methodology is an integrated approach. It is established by modelling LSCM G2B2C2 Platform in maritime safety/security logistics and applied to the enhancement of maritime safety/security in global LSCM. This paper externally contributes to the reduction of world maritime accidents and exalt the national prestige; internally, the enhancement of the national competitiveness through the improvement of shipping port logistics and others. These eventually contribute to Korea's economic development that is combined by both theory and practice and of practical use of the integrated approach.

• Journal of Navigation and Port Research
• /
• v.35 no.10
• /
• pp.837-846
• /
• 2011

Due to its vast range of areas and scopes of port logistics, professional training for port logistics experts has faced a limitation to raise manpower that the nation and companies ask for. This study looks at the current and expected demand and supply of workforce to identify necessary subjects and competitive factors in secondary education for training port logistics experts. Based on previous studies, this study proposes an assessment model by eliciting the priority of subjects in secondary education. and then, provides reasons for decision making.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2012.06a
• /
• pp.273-274
• /
• 2012

Companies are facing challenges to have high competitiveness because of continuous oil price rising and CO2 emissions regulations. Thus, companies are trying hard to construct effective logistics and operation system to achieve high customer service quality and saving cost. Also the ec-friendly idustrial complex is needed. Busan is in process to construct GILC(Global Industry Logistics City) in west Busan province to achieve high competitiveness and support lack of industrial complex. To construct this kind of logistics industrial complex, it needs logistics system through proper policy and freight transportation co-operation. Especially, efficient management through logistics hierarchy construction in industrial complex is very important for low cost and eco-friendly point of view. Therefore, this paper aims to analyze logistics system and suggest operation model to present logistics complex construction base data.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2021.11a
• /
• pp.101-103
• /
• 2021

With the rapid increase in the quantity of goods transported worldwide, companies are now started to show great interest in unmanned automated warehouses along with related research and development due to the increase of warehouse efficiency and reduction warehouse manpower. In a number of small warehouses, shuttle rack-based layouts that can handle inventory flow flexibly. However, the shuttle rack-based logistics center does not operate in case of emergency situations (faults, power outages, etc.), which seriously affects the efficiency and inventory management of the entire logistics center. Accordingly, in shuttle rack-based logistics center, we have classified various shuttle passages and RTV passages by layout and have analyzed its characteristics and types, along with derived reliability for each layout. The loading rate was also derived differently according to the number of passages, and have compared and analyzed reliability and loading rate for each layout.