• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.1
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• pp.97-101
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• 2011

Quad band p-HEMT SP6T switch for handset applications was developed. To achieve the low insertion loss and high isolation, trade-off between "On" state and "Off" state was considered by optimization of unit cell. Especially, in case isolation between transmit port and receive port, it was achieved by large capacitors and miniaturization of chip size was achieved by common voltage control and ground using back via process. Designed SP6T switch has size of $950um{\times}100um$ and take into consideration the gate recess error, excellent loss and isolation was confirmed in operating frequency.

• Journal of agricultural medicine and community health
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• v.15 no.2
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• pp.89-96
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• 1990

The results of infection state of anisakid larvae and parasitic helminths in salmon and sea-trout which caught from Taep'o port. Kang-won do were as follows. 1) From twelve specimens of sea-trout. 122 individuals of anisakid larvae were found and mean infection number of anisakid larvae per individual sea-trout was 10.17. 2) From total extracted anisakid larvae from sea-trout. 37 larvae(30.3%) were found in the muscle. This percentage was lower than that of salmon. but higher than that of other sea-fishes. 3) The taxonomic list of parasitic helminths which found in salmon and sea-trout was as follows. Class Trematoda Family Hemiuridae l. Brachyphallus crenatus(Rudolphi. 1802) 2. Lecithaster salmonis Yamaguti. 1934 Class Cestoda Family Phllobothriidae 3. Pelichnibothrium speciosum Monticelli, 1889-larval form Family Tentacuariidae 4. Tentacularia sp. - larval form 4) Among those 4 species of helminths. B.crenatus. L.salmonis, P.speciosum were the first recording species in Korea.

• Journal of Korea Ship Safrty Technology Authority
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• s.31
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• pp.81-96
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• 2011

The transportation of oil has increased due to the growth of marine industries and oil refineries. Oil residues and waste discharged to the ocean has increased due to accidental and/or intentional discharges. The International Marine Organization(IMO) has made compulsory that every oil tanker of 150 gross tonnage and above and every ship of 400 gross tonnages other than tankers and above should be provided with an oil record book. The entries in the oil record book should be made in accordance with the IMO guidelines. Specifically, engine room generated oil residues should be recorded in the oil record book from January 1, 2011. Also, the developed IMO guideline should be added for the prevention of dispute with the Port State Control Officers and(or) Tanker Vetting Inspectors. This oil record book will be in operation and of valued assistance to the marine officers, according to the IMO policy for the prevention of the waste oil and the oil mixtures from the machinery space. For the convenience, added Code & Item No. list, FAQs and reviewed and revised Examples.

• Journal of Navigation and Port Research
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• v.31 no.7
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• pp.579-587
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• 2007

Samchunpo(Sin Hyang) Harbor is located in the bay of Sa Chun, the central south coast of Korean peninsula. The harbor and coastal boundaries have been protecting by natural coastal islands and shoals. Currently, The Sin Hyang harbor needs maintenance and renovation of the sheltered structures against the weather deterioration and typhoon damages. Consequently to support this, the calculation of accurate design wave through the typhoon wave attack is necessary. In this study, calculation of incident wave condition is simulated using steady state spectrum energy wave model(wide area wave model) from 50 years return wave condition. And this simulation results in wide offshore area were used for the input of the extended mild slope wave model at the narrow coastal area. Finally, the calculation of design wave at Sin Hyang harbor entrance was induced by Boussinesq wave model(detail area wave model) simulation. The numerical model system was able to simulate wave transformations from generation scale to shoreline or harbor impact. We hope these results will be helpful to the engineers doing placement, design, orientation, and evaluation of a wide range of potential solutions in this area.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.06b
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• pp.391-396
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• 2006

In container terminal ship load planning for efficient loading is made before the ships arrive, But sometimes real loading state of the ship is different from planned loading state. And the planning is not available. So ship load planning must be adjusted in realtime. In this study we organize the situations said before. And we present realtime ship load planning method The method is suitable for the situations, rational, and immediately able to use.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.3
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• pp.125-138
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• 2011

This study was conducted to investigate the benthic condition around Busan Port by analysing spatio-temporal distribution pattern of polychaete community and some benthic environmental factors. Field survey was seasonally carried out at 15 stations covering in and outside of Busan Port from February to December, 2007. Water temperature, salinity and the type of surface sediment showed little changes among the stations, but factors related to organic enrichment such as TOC, AVS, coprostanol showed an obvious contrast, especially between in and outside of Busan Port. A total of96 species occurred and mean density was 1,814 ind./$m^2$. Species richness was higher at outer port than inner port, but density was higher at inner port. Dominant species were Aphelochaeta monilaris, Magelona japonica, Pseudopolydora paucibranchiata, etc. and many of them were typical species of organically enriched area. From the multivariate analyses, the whole study area was composed of two distinct polychaete communities located at the inside and outside of the port, and seasonal changes didn't have any influential effects on the structure. Coprostanol and AVS, indicators of organically enriched condition, well explained the community structures of polychaete worms in the vicinity of Busan Port. In this context, the innermost area of North Harbor was in a highly enriched state.

• Journal of Ocean Engineering and Technology
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• v.33 no.6
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• pp.564-572
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• 2019

Numerical simulation of the sediment by the Delft3d model was conducted to examine the changes in the sediment budget transport caused by long-term wave changes at the Maengbang beach. Representative waves were generated with input reduction tools using NOAA NCEP wave data for about 40 years, i.e., from January 1979 to May 2019. To determine the adequacy of the model, wave and depth changes were compared and verified using wave and depth data observed for about 23 months beginning in March 2017. As a result of the error analysis, the bias was 0.05 and the root mean square error was 0.23, which indicated that the numerical wave results were satisfactory. Also, the observed change in depth and numerical result were similar. In addition, to examine the effect due to long-term changes in the waves, the NOAA wave data classified into each of the representative wave grades, and then the annual trend of the representative wave was analyzed. After deciding the weight of each wave class considering the changed wave environment in 2100, the amounts of sedimentation, deposition, and the sediment transport budget were reviewed for the same period. The results indicated that the sedimentation pattern did not change significantly compared to the current state, and the amount of the local sediment budget shown in the present state was slightly less. And there has been a local increase in the number of sediment budget transport, but there is no significant difference in the net and amount of sediment movements.

• Journal of Navigation and Port Research
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• v.32 no.5
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• pp.379-385
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• 2008

In this paper, we presents a scheme for the parameter estimation and optimal control scheme for apparatus of container crane system. For parameter estimation, first, we construct the open loop of the container crane system and estimate its parameters based on input-output data, a real-coded genetic algorithm(RCGA) and the model adjustment technique. The RCGA plays an important role in parameter estimation as an adaptive mechanism. For controller design, state feedback gain matrix is searched by another RCGA and the estimated model. The performance of the proposed methods are demonstrated through a set of simulation and experiments of the experimental apparatus.

• Journal of Forest and Environmental Science
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• v.29 no.4
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• pp.257-274
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• 2013

Ecological and ethnomedicinal survey of plants was conducted in one hundred and twenty homesteads in Mbala, Amuda, Umuaku, and Nneato communities of Nneochi Local Governement Area, Abia State-Nigeria. A total of ninety-one medicinal plant species belonging to seventy-eight genera and forty-eight families, used in the treatment of malaria, yellow fever, fibroid, hepatitis, convulsion, hypertension, diabetes, insomnia, ulcer, rashes, low sperm count, snake bite, among others, were documented. Plant remedies were prepared mostly as infusions or decoctions from different plant parts with mainly water, and palm wine/gin sometimes. The highest number of medicinal plant species (73) was recorded in Mbala, followed by Amuda (71), Umuaku (68) and Nneato (61). Medicinal plant species diversity was highest in Amuda (Simpson 1-D=0.9621;H=3.663), followed by Umuaku (Simpson 1-D=0.9481; H=3.471), Mbala (Simpson 1-D=0.9345; H=3.341), and Nneato (Simpson 1-D=0.9307; H=3.277), respectively. Similarity in medicinal plant species was highest between Umuaku and Nneato (76.71%), followed by Amuda and Umuaku (75.95%), Mbala and Amuda (71.43%), while Mbala and Nneato had the lowest similarity (59.52%). The results of the study showed that traditional medicine is pivotal in the treatment of ailments in the study area, and that the indigenous people of Nneochi have recognized the need to conserve medicinal plants of importance ex situ within homesteads due to threats from unsustainable exploitation and deforestation.

• Journal of Ocean Engineering and Technology
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• v.34 no.6
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• pp.436-441
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• 2020

Wave field changes resulting from artificial coastal structures constructed in coastal zones have emerged as a major cause of beach erosion, among other factors. The rates of erosion along the eastern coast of Korea have varied mainly owing to the construction of various ports and coastal structures; however, impact assessments of these structures on beach erosion have not been appropriately conducted. Thus, in this study, a methodology to assess the impact of erosion owing to the construction of artificial structures has been proposed, for which a parabolic bay shape equation is used in determining the shoreline angle deformation caused by the structures. Assuming that the conditions of sediment or waves have similar values in most coastal areas, a primary variable impacting coastal sediment transport is the deformation of an equilibrium shoreline relative to the existing beach. Therefore, the angle rotation deforming the equilibrium of a shoreline can be the criterion for evaluating beach erosion incurred through the construction of artificial structures. The evaluation criteria are classified into three levels: safety, caution, and danger. If the angle rotation of the equilibrium shoreline is 0.1° or less, the beach distance was considered to be safe in the present study; however, if this angle is 0.35° or higher, the beach distance is considered to be in a state of danger. Furthermore, in this study, the distance affected by beach erosion is calculated in areas of the eastern coast where artificial structures, mainly including ports and power plants, were constructed; thereafter, an impact assessment of the beach erosion around these areas was conducted. Using a proposed methodology, Gungchon Port was evaluated with caution, whereas Donghae Port, Sokcho Port, and Samcheok LNG were evaluated as being in a state of danger.