• Journal of the Korean Society of Marine Environment & Safety
• /
• v.21 no.3
• /
• pp.259-265
• /
• 2015

It is clearly understood that e-navigation is beneficial to prevent collision and grounding of ships. The purpose of this study is to define and present a future ship operation system under the e-navigation environment in order to provide clear direction for the design of Korean e-navigation system. The future ship operation system consists of shipboard navigational system, shore supporting system and maritime communication system. To achieve the objectives of this study, the ship operation system was discussed separately into SOLAS ships and non-SOLAS ships in this study. In SOLAS ships, mariners become a system manager, choosing system presets, interpreting system output, and monitoring vessel response. In small ships and fishing vessels, mariners may enjoy their navigation by using the automatic tracking of ship's position on the portable electronic chart display. The improved bridge design, integrated and harmonized navigational system and single window reporting will reduce significantly the administrative and physical workload of mariners. Mariners can concentrate their attention more on navigational duty under the e-navigation environment. To build an effective Korean e-navigation system, the essential navigational functions and e-navigation services for small ships and fishing vessels must be identified and developed taking into account user needs.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.3 no.1
• /
• pp.27-36
• /
• 2011

In the proposed paper numerical calculations are carried out using two versions of a three-dimensional, timedomain panel method developed by the group of Prof. P. Sclavounos at MIT, i.e. the linear code SWAN2, enabling optionally the use of the instantaneous non-linear Froude-Krylov and hydrostatic forces and the fully non-linear SWAN4. The analytical results are compared with experimental results for three hull forms with increasing geometrical complexity, the Series 60, a reefer vessel with stern bulb and a modern fast ROPAX hull form with hollow bottom in the stern region. The details of the geometrical modeling of the hull forms are discussed. In addition, since SWAN4 does not support transom sterns, only the two versions of SWAN2 were evaluated over experimental results for the parent hull form of the NTUA double-chine, wide-transom, high-speed monohull series. The effect of speed on the numerical predictions was investigated. It is concluded that both versions of SWAN2 the linear and the one with the non-linear Froude-Krylov and hydrostatic forces provide a more robust tool for prediction of the dynamic response of the vessels than the non-linear SWAN4 code. In general, their results are close to what was expected on the basis of experience. Furthermore, the use of the option of non-linear Froude-Krylov and hydrostatic forces is beneficial for the accuracy of the predictions. The content of the paper is based on the Diploma thesis of the second author, supervised by the first one and further refined by the third one.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.18 no.4
• /
• pp.308-315
• /
• 2012

Hebei Spirit Oil Spill that happened in 2007 had prompted the need of revisiting the coastal safety. In response to this, Korea had made an effort to implement VTS in every coastline in the country. There are a lot of theoretical studies on VTS function nowadays, but coastal VTS are less frequently studied. In this paper, performance analysis results and accident prevention activities of Jindo Coastal VTS center were summarized and the Coastal VTS function are investigated. Jindo Coastal VTS covers relatively wide area and various places with various maritime traffic characteristics are the major navigation vessels, which means that it is important to control these vessels. Since the probability of accidents due to human error is relatively high in coastal area due to negligence tendency of crews during coastal area navigation, coastal VTS has to provide sufficient assistance to navigating vessels. Like most harbour VTS, Coastal VTS provides not only main information service, navigational assistance and traffic organization services but also various services related with advanced search-and-rescue assistance, marine national security, maritime crime prevention, oil spill response, traffic services for non-service vessel, and safety supervision for water leisure boats.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.17 no.2
• /
• pp.119-125
• /
• 2021

Subsea pipelines are widely used to transport hydrocarbons from ultra-deep seawater to facilities on the coast. A sandwich pipe is a pipe-in-pipe system in which the annulus between the two concentric steel pipes is filled with polymer cores and fillers for insulation and structural reinforcement. Sandwich pipeline is always exposed to complex loading such as bending moment, bulking, internal and external pressures caused by installation, operation and environmental factors. This research provides insights into the structural integrity of sandwich pipeline exposed to complex loading conditions using a linear matching method (LMM). The finite element model of the sandwich pipeline has been generated from previous research, and the model validation is performed by comparing the results of the linear analysis between the two models. The temperature dependent material properties are used to simulate the behavior of real pipeline, and the elastic-perfectly plastic (EPP) model has been taken into account for the material non-linearity. Numerical results provide comprehensive insights into the structural response of the sandwich pipeline under monotonic and cyclic loading and provide notable points about the evaluation of the plastic collapse limit and the elastic shakedown limit of the sandwich pipeline.

• Journal of Life Science
• /
• v.27 no.1
• /
• pp.78-88
• /
• 2017

Angiogenesis, the formation of new blood vessels, plays an important role in tumor growth and metastasis; therefore, it has become an important target in cancer therapy. Novel anticancer pharmaceutical products that have relatively few side effects or are non-cytotoxic must be developed, and such products may be obtained from traditional herbal medicines. Coptis chinensis Franch. is an herb used in traditional medicine for the treatment of inflammatory diseases and diabetes. However, potential antiangiogenic effects of C. chinensis water extract (CCFWE) have not yet been studied. The purpose of this study was to determine the antiangiogenic effect of CCFWE in order to evaluate its potential for an anticancer drug. We found that the treatment with CCFWE inhibited the major steps of the angiogenesis process, such as the endothelial cell proliferation, migration, invasion, and capillary-like tube formation in response to vascular endothelial growth factor (VEGF), and also resulted in the growth inhibition of new blood vessels in an ex vivo rat aortic ring assay. We also observed that CCFWE treatment arrested the cell cycle at the G0/G1 phase, preventing the G0/G1 to S phase cell cycle progression in response to VEGF. In addition, the treatment reduced the VEGF-induced activation of matrix metalloproteinases 2 and 9. Taken together, these findings indicate that CCFWE should be considered a potential anticancer therapy against pathological conditions where angiogenesis is stimulated during tumor development.

• Ocean policy research
• /
• v.33 no.2
• /
• pp.83-119
• /
• 2018

Under the Korean Marine Environment Management Act (hereunder, the KMEMA), the duty to arrange spill clean-up equipments, including spill clean-up vessels, required by the article 67 of the KMEMA is in essence the provision of public goods since it is a precautionary or preventive measure for the efficient performance of oil spill cleaning up. Also the obligation to control marine pollution and the duty to arrange of anti-pollution measures imposed on polluters is the obligation imposed by the public law in accordance with "the Polluter-Pays Principle". Therefore, the execution of such obligations shall be accompanied by the minimum legal and institutional arrangements. On the other hand, judging whether to form the roles of the public and private sectors in providing public goods is basically a matter of policy decision. However, even if the private sector is allowed to participate in the provision of public goods, it is imperative that a minimum requirement be provided to secure the public interest. Although major countries allows polluters to conclude a preliminary contract with a civil anti-pollution management company, these civilian institutions are in principle constituted by the owners of oil storage facilities. Additionally it is worth noting that it operates as a non-profit organization. In particular, if the practitioner performs pollution control for commercial purposes, their profitability may depend on the size of the pollution, the period spent on pollution control, the size of the equipment and manpower mobilized in the pollution control, and so on. Considering the above problems, caution should be taken to allow marine environmental management companies to be un-limitedly entrusted with the responsibility of arranging measures such as pollution control. In order to allow the marine environmental management contractor to be entrusted for the assignment of duty to protect the marine environment, the marine environment management business should be expanded so that the marine pollutant management capacity satisfies the statutory control capacity. For this purpose, it is necessary to manage and supervise the maintenance and improvement of the control capability of the marine environment management business. It is also necessary to discuss the introduction of the grading system for the control ability of the civil control companies alike in major countries.

• The Korean Journal of Pharmacology
• /
• v.30 no.2
• /
• pp.227-242
• /
• 1994

The general pharmacological effects of a new anthracycline anticancer agent, DA-125 $[7-0-(2,\;6-dideoxy-2-fluoro-{\alpha}-L-talopyranosyl)-adriamycinone-14-{\beta}-alaninate{\cdot}HCI]$ were investigated in mice, rats, guinea pigs, rabbits and dogs. Intravenous administration of DA-125 presented no significant effects on the central and peripheral nervous systems of ICR mice except a decrease in the numbers of acetic acid-induced writhing response at a dose of 10 mg/kg. In anesthetized rats and dogs, DA-125 produced a transient depression of blood pressure and an increase in heart rate, but did not affect the peripheral blood flow in the isolated ear vessels of rabbits and the mechanical functions of the isolated hearts of guinea pigs. No significant effects were observed on the gastrointestinal functions and the contractilities of smooth muscle preparations obtained from guinea pig trachea, rabbit ileum, pregnant and non-pregnant uterus and vas deferens of rats. DA-125 Increased the contractility of the isolated ileum of guinea pigs in a dose range of $10^{-6}{\sim}10^{-9}g/ml$, and also increased, but weaker than adriamycin, the vascular permeability in rat skin. DA-125 had no effect on the kallikrein-induced increase in permeability and the permeability of the visceral organs. DA-125 did not adversely affect the liver function and the blood coagulation system, and did not induce hemolysis in vitro. It is concluded from the results that the general pharmachological effects of DA-125 are similar to or weaker than those of adriamycin, and that little adverse effects are anticipated with a therapeutic dose range.

• The Korean Journal of Physiology and Pharmacology
• /
• v.25 no.4
• /
• pp.281-296
• /
• 2021

The beneficial effects of hypoxic preconditioning are abolished in the diabetes. The present study was designed to investigate the protective effects and mechanisms of repeated episodes of whole body hypoxic preconditioning (WBHP) in db/db mice. The protective effects of preconditioning were explored on diabetes-induced vascular dysfunction, cognitive impairment and ischemia-reperfusion (IR)-induced increase in myocardial injury. Sixteen-week old db/db (diabetic) and C57BL/6 (non-diabetic) mice were employed. There was a significant impairment in cognitive function (Morris Water Maze test), endothelial function (acetylcholine-induced relaxation in aortic rings) and a significant increase in IR-induced heart injury (Langendorff apparatus) in db/db mice. WBHP stimulus was given by exposing mice to four alternate cycles of low (8%) and normal air O₂ for 10 min each. A single episode of WBHP failed to produce protection; however, two and three episodes of WBHP significantly produced beneficial effects on the heart, brain and blood vessels. There was a significant increase in the levels of brain-derived neurotrophic factor (BDNF) and nitric oxide (NO) in response to 3 episodes of WBHP. Moreover, pretreatment with the BDNF receptor, TrkB antagonist (ANA-12) and NO synthase inhibitor (L-NAME) attenuated the protective effects imparted by three episodes of WBHP. These pharmacological agents abolished WBHP-induced restoration of p-GSK-3β/GSK-3β ratio and Nrf2 levels in IR-subjected hearts. It is concluded that repeated episodes of WHBP attenuate cognitive impairment, vascular dysfunction and enhancement in IR-induced myocardial injury in diabetic mice be due to increase in NO and BDNF levels that may eventually activate GSK-3β and Nrf2 signaling pathway to confer protection.

• Journal of Veterinary Clinics
• /
• v.39 no.4
• /
• pp.177-184
• /
• 2022

Caval syndrome is a severe complication of canine heartworm disease in which affected dogs present with various clinical signs that are often life-threatening. In cases of severe infection, adulticidal treatment has numerous complications as a result of a marked immune response against dead worms. Therefore, several surgical and non-surgical methods, including interventional extraction, have been applied in veterinary medicine. Despite the usefulness and efficiency of conventional retrieval devices, a few associated limitations must be addressed to reduce their risks and increase their applicability. Herein, we introduced a case of treating three dogs with caval syndrome by applying a newly developed heartworm basket device. The dogs were diagnosed with heartworm disease by heartworm antigen testing and direct smear. Imaging findings revealed remarkable remodeling of the right heart and pulmonary vessels and the presence of heartworms in the right heart. Additionally, heartworms were confirmed in the distal part of the abdominal aorta and femoral arteries in one dog, indicating aberrant systemic migration of the worms. Under general anesthesia, the heartworm basket device was introduced into the right heart via femoral venotomy and arteriotomy in one dog and jugular venotomy in the other two dogs. Although the number of cases in this study was small, the basket device was successful in gradual and cautious extraction of the heartworms in all three dogs. They exhibited good prognosis of clinical symptoms as indicated by imaging analyses.

• Journal of Intelligence and Information Systems
• /
• v.26 no.4
• /
• pp.87-109
• /
• 2020

Currently, thanks to the major stride made in developing wired and wireless communication technology, a variety of IT services are available on land. This trend is leading to an increasing demand for IT services to vessels on the water as well. And it is expected that the request for various IT services such as two-way digital data transmission, Web, APP, etc. is on the rise to the extent that they are available on land. However, while a high-speed information communication network is easily accessible on land because it is based upon a fixed infrastructure like an AP and a base station, it is not the case on the water. As a result, a radio communication network-based voice communication service is usually used at sea. To solve this problem, an additional frequency for digital data exchange was allocated, and a ship ad-hoc network (SANET) was proposed that can be utilized by using this frequency. Instead of satellite communication that costs a lot in installation and usage, SANET was developed to provide various IT services to ships based on IP in the sea. Connectivity between land base stations and ships is important in the SANET. To have this connection, a ship must be a member of the network with its IP address assigned. This paper proposes a SANET-CC protocol that allows ships to be assigned their own IP address. SANET-CC propagates several non-overlapping IP addresses through the entire network from land base stations to ships in the form of the tree. Ships allocate their own IP addresses through the exchange of simple requests and response messages with land base stations or M-ships that can allocate IP addresses. Therefore, SANET-CC can eliminate the IP collision prevention (Duplicate Address Detection) process and the process of network separation or integration caused by the movement of the ship. Various simulations were performed to verify the applicability of this protocol to SANET. The outcome of such simulations shows us the following. First, using SANET-CC, about 91% of the ships in the network were able to receive IP addresses under any circumstances. It is 6% higher than the existing studies. And it suggests that if variables are adjusted to each port's environment, it may show further improved results. Second, this work shows us that it takes all vessels an average of 10 seconds to receive IP addresses regardless of conditions. It represents a 50% decrease in time compared to the average of 20 seconds in the previous study. Also Besides, taking it into account that when existing studies were on 50 to 200 vessels, this study on 100 to 400 vessels, the efficiency can be much higher. Third, existing studies have not been able to derive optimal values according to variables. This is because it does not have a consistent pattern depending on the variable. This means that optimal variables values cannot be set for each port under diverse environments. This paper, however, shows us that the result values from the variables exhibit a consistent pattern. This is significant in that it can be applied to each port by adjusting the variable values. It was also confirmed that regardless of the number of ships, the IP allocation ratio was the most efficient at about 96 percent if the waiting time after the IP request was 75ms, and that the tree structure could maintain a stable network configuration when the number of IPs was over 30000. Fourth, this study can be used to design a network for supporting intelligent maritime control systems and services offshore, instead of satellite communication. And if LTE-M is set up, it is possible to use it for various intelligent services.