• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.113-124
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• 2019

The purpose of the study was to investigate the effects of sea cucumber extract on skin as a natural cosmetics functional material. Subjective evaluation of cosmetics before and after were conducted with questionnaires regarding moisture content, sebum content, melanin index, and erythema index. Experiments were conducted on improvement efficacy using skin clinical trials and questionnaires to evaluate changes in perception of skin condition and efficiency of products. With the aim of minimizing skin irritation, the efficiency of the solvent used for extraction was an important factor, and the sea cucumber extract was harvested with efficient extraction conditions at a ratio of 1:10 of 50% ethanol. The study aimed to identify the suitability of sea cucumber extract as a functional cosmetics material to improve the moisturizing ability of skin and its effect on the skin by adding marine natural animal sea cucumber extract. Clinical studies on cosmetics skin containing sea cucumber extract, excellent skin improvement effect from all items of clinical experiment in experimental and control groups. Sea cucumber extract was proved to be a stable, non-adverse physiologically active substance against abnormal symptoms or side effects of skin reactions and skin problems. In addition, the study found excellent results that can lead to its use as a cosmetics material. This is expected to contribute to the development of various cosmetics industries.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.462-467
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• 1993

Even nowadays ships on the sea are important strategic base for aircraft and missiles. Thus we have been studying an unmanned attack system against ships recently. We experienced severa problems when this system was simulated on the computer. In this paper, problems and solutions of an Air-To-Sea Guided Bomb for this system are presented.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.419-422
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• 2005

This paper is examined the properties of Haeju sea sand for concrete. As result, the water absorbtion ratio and the contents of shell and microfines of Haeju sea sand was high. We would expected to utilize the results of this study as a basic data for quality control of Ready Mixed Concrete.

• Journal of Life Science
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• v.10 no.5
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• pp.447-455
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• 2000

A eight weeks feeding experiment was conducted to investigate the effects of different dietary dimethyl-$\beta$-propiothetin (DMPT) levels on growth and chemical components in red sea bream (Pagrus major). The content of DMPT extracted from Ulva pertusa by auroclaving was 32.5mg%. Body weight gain, feed efficiency and feed intake were significantly increased with dietary DMPT level. After eight weeks of feeding trial, moisture content decreased with supplemented DMPT level, while crude protein and lipid contents increased with dietary DMPT level. Amino acid contents of muscle was elevated in the DMPT added groups compared to control group. Amino acid composition of muscle in fish fed the diets supplemented DMPT was not different to that of control group. Fatty acid contents of muscle in fish increased with dietary DMPT level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.2
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• pp.91-97
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• 2004

Applications of probiotics to shrimp ponds were carried out to determine their effects on water quality. Fermented solutions consisting of Bacillus spp. and Nitrosomonas spp. were applied to a 4 ha shrimp (Fenneropenaeus chinensis) pond from July to September, 2000. In the pond treated with probiotics, daily variations of DO and pH, and concentrations of DIN and DIP were lower than those in the ponds without probiotic treatment. Concentration of phytoplankton was less variable and the number of species was more variable in the probiotic-treated pond than those in the control pond. Variation of bacterial numbers and the number of Vibrio spp. were lower in the treated pond than those in the control pond. It is confirmed that the probiotics can be used to improve water quality of the shrimp ponds.

• Journal of the korean society of oceanography
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• v.37 no.3
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• pp.117-124
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• 2002

Anthropogenic changes have been made to the water budget for the Mediterranean Sea as a result of river diversion projects. The decrease in freshwater inflow to the Mediterranean represents an effective increase in the overall net evaporation over the basin. Hydraulic control models for the exchange between the Mediterranean and Atlantic through the Strait of Gibraltar predict that the salinity of the Mediterranean should increase if the net evaporation over the Mediterranean increases. Increases in the salinity of the deep waters in both the western and eastern Mediterranean basins have been observed. The causes of such higher deep water salinity are attributed to increases in intermediate water salinity which are ultimately mixed down into the deep sea during wintertime buoyancy loss events. The pattern of the Mediterranean salinity increase is instructive for understanding how the water mass properties in a basin change over time as a result of anthropogenic changes.

• Journal of Communications and Networks
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• v.11 no.4
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• pp.384-389
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• 2009

Optical wireless communication (OWC) systems are rapidly gaining popularity as effective means of transferring data at high rates over short distances. OWC facilitates rapidly deployable, lightweight, high-capacity communication without licensing fees and tariffs. Nevertheless, the performance of this new technology depends strongly on the atmospheric conditions and the characteristics of the link. In this work, we study the influence of these parameters on both the average (ergodic) capacity and the outage capacity of an OWC system over moderate to strong turbulence channels modeled by gamma-gamma distribution. Moreover, we compare the results that we obtain estimating the average and outage capacities.

• Progress in Superconductivity and Cryogenics
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• v.23 no.3
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• pp.10-13
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• 2021

The method of removing micro-plastics from sea water has been developed using electro-magnetic force. Plastics are difficult to decompose and put a great load on the marine environment. Especially a plastic with a size of 5 mm or less is defined as micro-plastic and are carried by ocean currents over long distances, causing global pollution. These are not easily decomposed in the natural environment. The Lorentz force was generated in simulated sea water and its reaction force was applied to the micro-plastic to control their motion. Lorentz force was generated downward and the reaction force to the plastics was upward. The plastic used in the experiment was polystyrene with a diameter of 6 mm, and the density was 1.07 g/cm³. The polystyrene sphere levitated at the current density of 0.83 A/cm² and the external field of 0.87T. The particle trajectory calculation was also made to design separation system using superconducting magnet.

• Journal of Ocean Engineering and Technology
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• v.23 no.3
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• pp.53-58
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• 2009

A scale model test for ship Infra-Red signature measurements at sea is impossible, because it is sensitive to the environment. Since we can't control the meteorological environment of the real sea, it can't be carried out with the desired maritime environments. Therefore, in the sea, we made measurements of the weather, operating conditions of the ship, and ship IR signatures under given conditions, and then analyzed them. Conversely, we compared the results of the test with a prediction for a given scenario condition. This paper describes the test items, procedures, and measuring instruments of the experiments at sea and the results from basic researches for methods of estimation and analysis of the measured data.

• Journal of applied mathematics & informatics
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• v.26 no.3_4
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• pp.519-530
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• 2008

This paper studies the multi-domain coupled system of one dimensional Arctic temperature field and establishes identification model about the thermodynamic parameters of sea ice (heat storage capacity, density and conductivity) by the so-called output least-square estimate according to the temperature data acquired by a monitor buoy installed in the Arctic ocean. By the optimal control theory, the existence and dependability of weak solution and the identifiability of identification model have been given. Moreover, necessary optimality condition is proposed. Furthermore, the optimal algorithm for the identification model is constructed. By using the optimal thermodynamic parameters of Arctic sea ice, the numerical simulation is implemented, and the numerical results of temperature distribution of Arctic sea ice are demonstrated.