• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.2
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• pp.93-103
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• 2009

To measure the mineral contents of marine invertebrates, we collected 239 individuals from 52 species from the east (Pohang), west (Gunsan), and south (Tongyeong) coasts of Korea: 34 species of molluscan shellfish (Gastropoda and Bivalvia), 6 species of Cephalopoda, 8 species of Crustacea, and 4 other species. The mean contents of the macro mineral in the 100g edible portion of molluscan shellfish were high in the oder of Na (355.1 mg), P (128.1 mg), K (110.8 mg), Mg (83.8 mg) and Ca (57.5 mg). And the mean contents of the micro mineral in the molluscan shellfish were high in the oder of Fe ($41.12{\mu}g/g$), Zn ($30.48{\mu}g/g$), Mn ($3.81{\mu}g/g$), Cu ($3.49{\mu}g/g$) and Ni ($0.35{\mu}g/g$). We could not observe clear regional variation in the mineral content of the molluscan shellfish species. The mean contents of the macro mineral in the 100g edible portion of other marine invertebrates (Cephalopoda, Crustacea, etc.) were high in the oder of Na (400.7 mg), P (145.1 mg), K (105.0 mg), Mg (63.2 mg) and Ca (49.0 mg). And the mean contents of the micro mineral in other marine invertebrates were high in the oder of Zn ($24.4{\mu}g/g$), Fe ($13.8{\mu}g/g$), Cu ($4.88{\mu}g/g$), Mn ($2.14{\mu}g/g$) and Ni ($0.12{\mu}g/g$). The daily average intakes of the macro mineral through fisheries products consisted of P (125.9 mg), Na (119.3 mg), K (101.8 mg), Ca (31.0 mg), Mg (27.6 mg). And the daily average intakes of the micro mineral through fisheries products consisted of Zn (0.92 mg), Fe (0.68 mg), Cu (0.12 mg) and Mn (0.07 mg). The respective intakes of the minerals (P, Mg, Na, Ca, K) from fish were about 18.0, 7.9, 8.0, 4.4 and 2.2% of the dietary reference intakes for Koreans (KDRIs) set by the Korean Nutrition Society. And the respective intakes of micro mineral (Cu, Zn, Fe, Mn) from fish were about 14.6, 9.2, 6.7, and 2.1% of the dietary reference intakes for Koreans (KDRIs). Therefore, fisheries products play a very important role as a source of mineral.

• Journal of Plant Biology
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• v.13 no.1
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• pp.13-24
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• 1970

This investigation was one of the series of ecological studies on the plant communities of Quelpart Island which was held in 1969. It was aimed at studying the ground vegetation of Torreya nucifera and the soil properties of the ground in which it grows. Observaton of the flora in a place where wild growth of Crinum maritimum, soil properties and distribution of micro-organisms in a place where wild growth occurs, were also made. 1) A few kinds which have important values among the ground vegetation fo Torreya nucifera forest are Liniope graminifolia, Convallaria keiskei, Sasaquelpaertensis, Carex kingiana, Pteridium aquilinum, Pyrola japonica, Hedera tobleri, etc. 2) While the studies of 25 Quadrats were being held, 29 species in A plot, 30 species in B plot, and 26 species in C plot have been found. 3) The kind which has the highest important value among the species located in naked plot(outside of Torreya nucifera forest) is Zoysia japonica and 18 other kinds were found. 4) The soil fertility through all depths are found higher in the forest soil than in that of open places. 5) P2O5, K, and total exchangeable bases etc. have shown the difference of contents according to the depth and generally had lower value as much as it goes down. 6) The content of N was a lot higher than any other forest soil and P2O5, K and total exchangeable bases seemed to be a little lower. 7) The overall flora of Todo consists of 71 species (9 species of wood plant and 62 species of herbs) added 28 kinds of non-reported species. 8) Themineral contents are the highest at a place of wind growth of Crinum maritimum which has much organic matter. The subsoil of this place is more fertile than surface soil. 9) The soil of Todo which is sandy soil, consists of shellfish shell and quartz, and has low fertility and alkali. 10) In the total occurrences of micro-organisms, bacteria was the greatest in number followed by actinomycete and fungi, in that order. 11) A survey of the soil depth and the ecological distributional pattern of micro-organismsm revealed that the number of micro-organisms is the greatest on the surface, gradually decreasing in proportion to the depth. 12) It was found that a comparatively greater number of micro-organisms occurred when the soil showed an adequate increase in water content.

• Journal of the Korean institute of surface engineering
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• v.41 no.6
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• pp.335-340
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• 2008

Cutting performance and wear behavior were studied with the diamond micro-blade of Cu/Sn bond materials containing various amount of lubricant materials such as graphite and $MoS_2$. Measurement of instantaneous electric power consumption for cutting glass workpiece at the constant velocity was conducted and proposed as a method to assess cutting efficiency. The energy consumption of micro-blade for glass cutting decreased with the content of graphite and $MoS_2$ while wear amount of blade in volume increased with the amount of lubricant addition during the dicing test. It is because that hardness, flexural strength, and fracture toughness ($K_{IC}$) reduced with the amount of lubricant addition. Blades with $MoS_2$ additive showed higher mechanical properties than those with graphite additives when the same amount of the lubricant additive in wt.% was added. Due to the lower density of graphite than $MoS_2$, higher volume fraction of graphite could result in stronger effect on lowering electric power consumption by reducing the friction between blade and work piece however increasing wear rate due to the reduction in strength and fracture toughness. Adhesive wearing mode of micro blade could be remarkably improved by the addition of graphite as well as $MoS_2$.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.552-554
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• 2004

Barrier ribs of plasma display panel (PDP) are glass matrix composite reinforced with alumina particles. Mechanical properties of the ribs are very crucial for the improvement in reliability of the panel as the ribs might fracture during transportation and service. In this study, therefore, the effects of filler type and content on the mechanical properties of the ribs were investigated. The fillers used include $Al_2O_3$, $TiO_2$, $ZrO_2$ and fused silica. The content of the filler was changed from 0 to 40 vol.%. The mechanical properties of the ribs measured were hardness, Young's modulus, fracture toughness, and 3-point bending modulus. The fracture toughness evaluated by micro-Vicker's indentation of the composites, in general, was measured to increase with the content of the filler until the sintered density does not decrease significantly. The improvement, however, was dependent on the type of filler employed.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.289-290
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• 2015

In this experiment, nitriding treatment has been performed at $400^{\circ}C$ with various $N_2$ content and with changing processing time on AISI 420 martensitic stainless steel to investigate the expanded martensite layer (${\alpha}^{\prime}_N$ layer) formation behavior. Nitriding was implemented with changing $N_2$ content from 10% to 25% for 15 hrs and processing time was changed from 4hr to 15hr at 25% $N_2$ content. After treatment, the behavior of the ${\alpha}^{\prime}_N$ layer was investigated by optical microscopy, X-ray diffraction, and micro-hardness testing. Potentiodynamic polarization test was also used to evaluate the corrosion resistance of the samples. It was found that the surface hardness and ${\alpha}^{\prime}_N$ layer thickness increases with increasing $N_2$ percentage and processing time. Although their corrosion behaviors are worse than the bare sample.

• Journal of ILASS-Korea
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• v.2 no.3
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• pp.8-16
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• 1997

Ta investigate characteristics and spray of emulsified fuet we are mixed water with diesel oil using ultrasonic energy fuel feeding system. Separation ratio of emulsified fuel was shown good condition that of water content is small and longer ultrasonic energy adding time. Viscosity of emulsified fuel increased 79% with addition to water content and surface tension increased 1.6% in comparision to pure diesel oil. The SMD of emulsified fuel adding ultrasonic energy decreased with 3% in comparision to pure diesel oil. With increasing 5, 10% water content the SMD decreased 15.6, 20.1% in comparision to pure diesel oil. The mind-explosion was investigated with 4step.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.554-559
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• 2011

To measure the proximate composition and mineral content of laver Porphyra yezoensis, we collected 30 raw and 30 dried laver from the major production area of the south coast of Korea (Busan, Goheung, Haenam, Wando). The approximate composition of a 100 g edible portion of raw laver was $89.9{\pm}1.4$ g moisture, $3.7{\pm}1.0$ g protein, $0.5{\pm}0.2$ g lipids, $2.1{\pm}1.8$ g carbohydrate and $3.9{\pm}0.6$ g ash. The approximate composition of a 100 g portion of dried laver was $8.9{\pm}1.6$ g moisture, $31.5{\pm}6.5$ g protein, $1.9{\pm}0.3$ g lipids, $48.4{\pm}6.5$ g carbohydrate and $9.3{\pm}1.1$ g ash. No clear regional variation in laver composition was observed. The mineral content of laver was expressed as dry weight. The mean macro mineral content per 100 g portion of raw laver was (in descending order): K ($1,979{\pm}863.0$ mg), Na ($1,063.2{\pm}498.8$ mg), P ($658.7{\pm}101.8$ mg), Mg ($432.3{\pm}83.5$ mg) and Ca ($394.2{\pm}136.5$ mg). In comparison, the mean micro mineral content of raw laver was (in descending order): Fe ($243.72{\pm}154.75\;{\mu}g/g$), Zn ($72.76{\pm}30.61\;{\mu}g/g$), Mn ($41.53{\pm}15.33\;{\mu}g/g$), Cu ($4.16{\pm}1.66\;{\mu}g/g$) and Ni ($0.43{\pm}0.70\;{\mu}g/g$) No clear regional variation in the mineral content of laver was observed; however, raw laver contained a higher mineral content than dried laver.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.232-239
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• 2009

Emerging social networking services provide a new paradigm for human-to-human communication. However, these services are centralized and managed by single service provider. In this paper, we propose MicroPost, a decentralized event notification service architecture for social applications based on publish/subscribe model. In our design space, event brokers are structured as an overlay network which provides the substrate of distributed peer-to-peer lookup service for storing and retrieving subscriptions with hashed keys. Event clients interact with event brokers to publish or subscribe social messages over the wide-area network. Using XML standards, we present an efficient algorithm to forward events for rendezvous-based matching in this paper. In our design space, the cost of routing is O(${\omega}log_kN$), where N is the number of event brokers, ${\omega}$ is the number of meta-data obtained from event messages, and k is a constant, which is selected by our design, to divide the identifier space and to conquer the lookup of given key. Consequently, what we achieved is an asynchronous social messaging service architecture which is decentralized, efficient, scalable, and flexible.

• Journal of Power System Engineering
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• v.17 no.6
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• pp.122-129
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• 2013

The microstructure and deformation behavior in 22Cr-0.2N micro-duplex stainless steels with various Ni and Mn contents were compared using by OM, TEM, and XRD. The 22Cr-0.2N duplex stainless steel plates were fabricated and hot rolled, followed by annealing treatment at the temperature range of $1,000-1,100^{\circ}C$. All the samples showed the common strain hardening behaviour during the tensile test at a room temperature. The steels tested at the temperatures of $-30^{\circ}C$ or $-50^{\circ}C$ showed a distinct inflection point in the stress-strain curves, which should be resulted from the formation of strain-induced martensite(SIM) of austenite phase. This was confirmed by TEM observations. The onset strain of a inflection point in a stress-strain curve should be depended up the value of $M_d30$. With the decrease of the tensile test temperature, the inflection point appeared earlier, and the strength and fracture strain were higher. The tensile behaviour was discussed from the point of austenite stability of the micro-duplex stainless steels with the different Ni and Mn content.

• Corrosion Science and Technology
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• v.17 no.1
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• pp.1-5
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• 2018

As structural materials, magnesium (Mg) alloys have been widely used in the fields of aviation, automobiles, optical instruments, and electronic products. There are few studies on the effect of coating conditions on the compositional variation during the formation process of the conversion coatings. Rare-earth based conversion coating on AZ91 magnesium alloy was prepared in ceric sulfate and hydrogen peroxide contained solution. The element composition and valence as well as their distribution in the coating were analyzed with energy dispersive X-ray spectroscopy (EDS), Electron probe micro-analyzer (EPMA), X-ray photoelectron spectroscopy (XPS). The effect of treating process on the element composition were also studied. It was found that the conversion coating surface consists of Mg, Al, O, Ce, and the weight content of Ce in the coating was affected by the treating solution concentration and immersion time; the Ce element was distributed in the coating non-uniformly and existed in the form of $Ce^{+3}$ and $Ce^{+4}$, while the O element existed in the form of $OH^-$, $O^{2-}$, $H_2O$. Based on microscopic analysis results, the electrochemical deposition mechanism on the micro-anode and micro-cathode in the process of the coating growth was suggested.