• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.359-367
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• 2005

In order to increase the productivity of container terminals, automation is being considered seriously in nowadays. A yard is usually automated by running autumated RMGs (rail mounted gantries) which may require somewhat a different stacking strategy to archive a better performance. In this paper, we present a simulation model for RMGs and summarize experimental results with two different stacking strategies applied to a horizontal block which has two non-crossable RMGs. The concentrating strategy, which stacks containers belong to a single ship together and dedicateds each RMG to either ship services or external truck services, showed a good performance in ship unloading. In the contrast, the distributing strategy, which partitions a block into two regions and binds each RMG to one of the regions to improve the productivity of ship services by running each RMG alternately, is suggested for blocks of exporting.

• Journal of Bio-Environment Control
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• v.33 no.3
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• pp.156-162
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• 2024

This study was conducted to investigate the effect of rooting volume on the productivity of fresh shoots when growing rosemary in multi-layer cultivation. The 10 cm middle cuttings from which the common rosemary (Rosmarinus officinalis L.) apical bud was removed were planted in a 128-hole tray, rooted, and then transplanted into pots of 125, 200, 550, 750, 1,300, and 2,000 mL to determine the growth characteristics and quantity of young shoots of 1-year-old and 2-year-old rosemary. In the case of 1-year-old rosemary, there was no clear difference in initial growth (30 days after transplanting) between treatments in pot size larger than 550 mL, in the case of 2-year-old rosemary, growth tend to be proportional as the pot became larger. The fresh weight of the underground part of 1-year-old and 2-year-old rosemary was the lowest at 6.9 g and 24.4 g, respectively, when surveyed on July 25 in a 550 mL container, and 10.3 g and 24.9 g, respectively, when surveyed on November 24, and there was a difference between treatments in containers of 750 to 2,000 mL. On the other hand, in the case of 1-year-old rosemary, the fresh weight of the above-ground part increased as the pot became larger, but there was no statistical difference above 1,300 mL, and the fresh weight of 2-year-old rosemary was also significantly higher as the pot became larger. The quality of young shoots was the best for 1-year-old rosemary in a pot of 2,000 mL, but for 2-year-old rosemary, there was a difference in quality depending on the season. Shoot productivity per unit pot was highest at 1,300 mL, but when converted to per unit area, the best was observed at 750 mL. Therefore, the most suitable pot size for intensive production through multi-layer cultivation of rosemary young shoots is judged to be 750 mL (12.5 × 11.5 cm).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.338-344
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• 1999

Floating debris was recorded from a training ship, $\sharp$1 Kwanaksan, of Pukyong National University with about 10 knots speed at July 15th and 20th of 1997. The sampled area is the middle of southern sea of Korea, divided into 44 unit segments on survey routes. Debris fabrication materials were categorized with 6 items using the following; man-made or natural wood items, paper and cardboard, nylon netting and rope, styrofoam, plastics, floating metal and glass containers. All identified items within a 100 $\pm$ 2 m wide band were recorded but ignored if beyond this boundary. The results of distribution and transport of floating debris in the area are as follows: 1. The quantities of debris during the survey were distributed from $1.6\~369.7\;items/km^2$. The most obvious trend is the widespread distribution of all debris. The highest densities of all debris were discovered in the coastal waters of Namhae and Yokji island, and of about 50 km off from the southward of Yokji and about 74 km off from the eastward of Komun island. Especially many of small styrofoams within $\phi$20 cm were observed in these segments. 2. Styrofoams and plastics were composed of $83.5\%$ among all debris, next woods items, $9.8\%$. 3. The quantities, distribution shapes and composition of debris were varied as the observed duration and the natures of each items. 4. These phenomena are concluded that firstly they depend on the river discharges included debris due to precipitation falls, secondly inflow or dumping debris are drifting to the off-shore by Kuroshio currents present at their adjacent sea, But on the basis of the observed data it is difficult that source position, quantities and inflow items of debris are identified, and also the transport processes is pursue. further more surveys are continuously being investigated, and from this it is hoped that a much wider coverage can be achieved, perhaps on all sites of the Coast of Korea and contributed to the stationary area, finding of sources, removal method of debris and resistants of marine productivity.

• Journal of Navigation and Port Research
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• v.44 no.3
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• pp.195-202
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• 2020

The production of larger of ships is a survival strategy for global shipping companies to pursue the economics of scale. According to this strategy, to respond to this situation, many containers are loading/unloading simultaneously in the hub port. Additionally, the container terminals are promoting the introduction of automation to expand the terminal facilities and increase efficiency/productivity of the container yards. European ports have introduced automation to address rising labor costs and shortages of labor. Recently, the construction of fully automated container terminals is increasing in the United States and China to resolve problems such as the slow growth of the global economy, the emergence of large ships, air pollution, and safety accidents. Domestic ports are at an early stage compared to the world's advanced container terminals, and countermeasures are being prepared to respond to the changing ports. However, research on the recognition difference analysis that examines the opinions of stakeholders is insufficient. As a result of analyzing the recognition among the groups, it was found that container terminal operators reduced labor costs, improved shipping services for shipping companies, prevented safety accidents for port union labor, and increased service for port authority and government agencies. Thus, to closely examine the perception among the groups, one-way ANOVA was performed, and then the implications were deduced as the basic data for the smooth introduction of automation.

• Journal of Navigation and Port Research
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• v.42 no.1
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• pp.47-56
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• 2018

In this study, the focus is on the issue of whether a container terminal is facing the limitation of its productivity for serving mega-vessels with numerous containers. In order to enhance the terminal operations, a new conceptual design of the container handling system have been proposed. This research focuses on the rail-based container transport system and its operations. This system consists of rail-based shuttle cranes and rail-based transporters called flatcars. The deadlock problem for managing automated transporters in container terminals has been an important issue for a long measurement of time. Therefore, this study defines the deadlock situation and proposes its avoidance rules at the rail-based container transport system, which is required to handle numerous container throughput operations. The deadlock in the rail-based container transport system is classified into two parts: deadlock between cranes and flatcars; deadlock between flatcars. We developed the simulation model for use with characterizing and analyzing the rail-based container transport system. By running the simulation, we derived possible deadlock situations, and propose the several deadlock avoidance algorithms to provide results for these identified situations. In the simulation experiments, the performances of the deadlock avoidance algorithms are compared according to the frequency of deadlocks as noted in the simulations.

• Journal of Korea Society of Industrial Information Systems
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• v.13 no.4
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• pp.64-72
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• 2008

Recently security is being an important issue in almost every field of industry. This situation has affected port logistics industry deeply. Ports are now leaving operational methods that only focus on productivity, and shifting to new ones which focus on safety and customer services on the basis of it. Thus a lot of companies and institutions have offered various solutions as this issue becomes more and more intense. Among them, most typical solutions involve installing special devices to ordinary containers to improve its security, such as CSD (Container Security Device) of GE (General Electric) and eSeal of Savi Networks. On the other hand, these devices focus only on international standards or technical implementation, and this causes inconvenience to actual users like cargo owners, sea carriers, or stevedoring companies. This is considered to be due to lack of sufficient consideration on user demands. This research uses QFD (Quality Function Deployment) method for deducting system requirements in order to solve the problems of previous security devices and to develop a security system that can not only reflect the demands of the users but also considers real-world conditions. According to the QFD results, a total of 21 system CTO's were deducted under 5 categories.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.63-70
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• 2002

The main subject to become a hub pen is automation The automated container terminal has already operated in advanced pons and it bas been planned for the basic planning and operation design in domestic case. The key of automated container terminal is effective operation of both ATC(automated transfer crane) and AGV(automated guided vehicle) which is automated handling equipments. This is essential to productivity of automated container terminal. This study suggests the moat optimal method of equipment operation in order to minimize loading time using each three types of effective AT operation methods and AGV dispatching rules in automated container terminals. As the automated equipment operation causes unexpected deadlocks or interferences, it should be proceeded on event-based real tine. Therefore we propose the most effective ATC operation methods and AGV dispatching rules in this paper. The various states occurred in real automated container terminals are simulated to evaluate these methods. This experiment will show the most robust automated equipment operation method on various parameters(the degree of yard re-marshaling, the number of containers and the number of AGVs).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.389-396
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• 1994

Poor establishment of white dover (Trifolium repens L.) into grass-dominant pastures has been limited its availability. The experiment was done to clarify the effects of timing of initial defoliation, defoliation frequency on the regrowth and nodule formation of the clover cultivars during 28-day regrowing period. Individual plants of cv. Regal, Louisiana S-1 (La. S-1), Grasslands Huia (Huia) and Aberystwyth S184 (S184) were grown in containers until grown to unifoliolate, 1, 2, 4, or 8 trifoliolate stage, and then clipped to 1cm in height every 7 or 28 day for 28 days. To measure the effects, plants were sampled immediately after final harvest, and 1, 3, 7, 14 and 28 days after the harvest. Shoot, root dry weight and biomass were reduced with earlier, more frequent defoliation or shorter regrowing period. In frequent defoliation shoot dry weight and biomass were increased with delayed initial defoliation while in less frequent defoliation steeply done when initial defoliation was delayed to 4 trifoliolate stage. Shoot /Root ratio inclined with more frequent defoliation or lengthened regrowing period, and was greater in initial defoliation of unifoliolate to 2 trifoliolate than the others. Although nodules no. per plant declined with earlier or more frequent defoliation, the effect disappeared to some extent after 14-day regrowth. In comparison with the others, Regal had the highest shoot. dry weight and biomass to 2 trifoliolate stage while S184 did the most nodules regardless of defoliation timing. On 7-day after last defoliation nodule formation of Regal, Huia and S184 but on 28-day after last defoliation that of La. S-1, Huia and S184 was positively correlated to shoot and root dry weights upto 2 trifoliolate stage. On the former day, however, that was negatively correlated to Shoot /Root ratio upto 1 trifoliolate stage although on the latter day it was not, meaning that in addition to more frequent defoliation earlier defoliation was harmful in nodule formation of white clover.