• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.29 no.6
• /
• pp.251-256
• /
• 2019

In the process of ZnO ceramic sintering at a temperature of 1385℃, higher than the normal sintering temperature, some grains were growth up to mm scale. When sintered at 1400℃ for 8 hours, the size of the grains that are not involved in the abnormal growth is as large as 30~40 ㎛, but the size of the abnormal grown grain reaches 1,000 ㎛, which is more than 10,000 times bigger in volume than the normal one within 8 hr growth. As a cause of rapid and abnormal grain growth, primary particle size distribution, compaction density variation within sample and doping of impurities could be considered. The primary particle size distribution could be considered main reason for abnormal grain growth but no solid evidence was obtained. Through the observation of the microstructure, it is presumed that the giant grains grow absorbing the neighbor grains through a grain rotation process.

• Fisheries and Aquatic Sciences
• /
• v.26 no.7
• /
• pp.447-454
• /
• 2023

Fast somatic growth is important considerations for successful and competitive aquaculture industry. In rainbow trout reared in South Korea, triploid induction was used to suppress negative influence of reproductive maturation to body growth. However, the effects of triploidy are visible in both mature fish and developing juvenile fish. Thus, it is also important to explicate the effect of triploid induction on growth during the early-life stages of rainbow trout-alevins and fry. Rainbow trout fertilized eggs were subjected to triploid induction and polyploidy was checked by flow cytometry. Diploid and triploid alevins and fry were reared separately in tanks with constant flow of freshwater through flow-through water system and growth measurements were done from zero days after hatching (DAH 0) until DAH 134. The egg-yolk morphometrics of alevins-yolk length, yolk height, yolk volume and yolk weight-were statistically similar (p > 0.05) in both genotypes from DAH 0 to DAH 22. The total length, body height, and body weight of alevins and fry were statistically better (p > 0.05) in both genotypes until DAH 92 but thereafter, triploid had a significantly better growth performance (p < 0.05) over diploid fish until the completion of study at DAH 134. With that, triploid induction did not influence alevin yolk regions and body growth and fry somatic growth until around 3 months after hatching, but considerable growth enhancement was subsequently apparent.

• Proceedings of the Korea Society of Information Technology Applications Conference
• /
• 2002.11a
• /
• pp.350-362
• /
• 2002

A new architecture called the Storage Area Network(SAN) was developed in response to the requirements of high availability of data, scalable growth and system performance In order to use SAN more efficiently, must SAN operating systems support storage virtualization concepts that allow users to view physical storage devices attached to SAN as a large volume virtually. A logical volume manager Days a key role in storage virtualization it realizes the storage virtualization by mapping logical addresses to physical addresses. In this paper, we design and implement an efficient and flexible mapping method for logical volume manager. The mapping method in this paper supports a snapshot that preserves a volume image at certain time and on-line reorganization to allow users to add or remove storage devices to SAN even while the system is running.

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2002.11a
• /
• pp.350-362
• /
• 2002

A new architecture called the Storage Area Network(SAN) was developed in response to the requirements of high availability of data scalable growth, and system performance. In order to use SAN more efficiently, most SAN operating systems support storage virtualization concepts that allow users to view physical storage devices attached to SAN as a large volume virtually. A logical volume manager plays a key role in storage virtualization. It realizes the storage virtualization by mapping logical addresses to physical addresses. In this paper, we design and implement an efficient and flexible mapping method for logical volume manager. The nin method in this paper supports a snapshot that preserves a volume image at certain time and on-line reorganization to allow users to add or remove storage devices to SAN even while the system is running.

• Journal of Climate Change Research
• /
• v.6 no.1
• /
• pp.1-10
• /
• 2015

Climate change lead to environmental pollution caused by the radical economic growth and development of industry. The amount of damage from abnormal climate is increasing rapidly for this reason in Korea. In particular, the cities is a lot of carbon emission quantity from the radical growth. Thus the government present "low carbon green growth" for eco-friendly city planning. As one of the important factors effecting climate change, active researches on land use change is performed. In this study, we knew land use change of each scenarios using land use equilibrium model which is kind of predictive model of land use in Japan. First, we selected study area to Jeju lsland. For this study, indicators for input data were selected and spatial data for input data were established using GIS program. Second, we established future scenarios based in 2040s. There are 2 future scenarios: dispersion scenario, compact scenario. Third, we compared with residential area of current and residential area for future scenarios. Results showed that residential area of the difference between current and dispersion scenario were 1,230 ha and residential area of the difference between current and compact scenario were 1,515 ha. Finally, for comparing carbon dioxide absorption volume between dispersion scenarios and compact scenarios, we calculated carbon dioxide absorption volume according to residential area decreased of each future scenarios. Results showed that carbon dioxide absorption volume in dispersion scenario was 477,878 ton and carbon dioxide absorption volume in compact scenario was 588,606 ton. Therefore, the study showed that land use equilibrium model is expected to put to use for future enhancement in creating data for climate change stabilization. And it is also expected to be utilized for city planning research in Korea.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.6 no.4
• /
• pp.521-531
• /
• 1996

Inorganic and inorganic/organic microcapsules were prepared by spray drying. $K_{4}SO$ and clay were used as the core and colloidal silica as the shell for the inoroganic microcapsules. Forthe inorganic/organic microcapsules were used the inorganic microcapsule which were mentioned above (core) and ethyl cellulose (shell). To characterize the prepared microcapsule for the practical use, the homogenity of surface and pore volume are the dominent factors. At the volume ratio of 0.3/0.7 of core/shell, the spherical and homogeneous surfaces of inorganic microcapsule could be synthesized. In the case of inorganic/organic microcapsules, the weitht ratio was 0.76/0.24. The pore volume of inorganic/organic microcapsules decreases more than that of inorganic microcapsule. The more the amount of shell (ethyl cellulose) in inorganic/organic microcapsules increases, the more the coating became homogeneous and the pore volume decreased.

• Journal of Korea Port Economic Association
• /
• v.22 no.3
• /
• pp.161-188
• /
• 2006

The purpose of this study is to analyze traffic volume between the Korean container ports located at the west coast and northern Chinese ports and then the distribution trend of container between Korea and China. The findings of the study are as follows. First, Container traffic between western Korean ports and northern Chinese ports has been increasing due to an increasing trade volume between both countries and geographical accessibility. Second, Seoul and neighboring area tend to use the trade route between the western ports and northern Chinese because of lower logistics costs and time-saved advantage compared to another ports. Third, the growth of the western ports did depend mainly on the northern China oriented growth. Such a fact could leads to the overlapping investment in port development in Korea and another intense competition among national ports to attract cargoes and liners. Therefore, port development policy considering the characteristics and function of national ports have to be established. and also alternatives and strategies for improving the competitive edge of small and medium sized shipping lines against the opening of shipping market have to be worked out.

• Journal of Oral Medicine and Pain
• /
• v.45 no.4
• /
• pp.83-88
• /
• 2020

Purpose: Growth differentiation factor 11 (GDF11) and myostatin (MSTN) are closely-related transforming growth factor β family members reported to play crucial roles in bone formation. We previously reported that, in contrast to MSTN, GDF11 promotes osteogenesis of vertebrae and limbs. GDF11 has been also reported as an important regulator in tooth development by inducing differentiation of pulp stem cells into odontoblasts for reparative dentin formation. The goal of this study was to investigate the differential roles of GDF11 and MSTN in dental and cranial bone formation. Methods: Micro-computed tomography analysis was performed on cranial bones, including frontal, parietal, and interparietal bones, and lower incisors of wild-type, Gdf11 knockout (Gdf11-/-), and Mstn knockout (Mstn-/-) mice. Tissue volume, thickness, and mineral density were evaluated for both cranial bone and lower incisors. Lower incisor lengths were also measured. Because Gdf11-/- mice die shortly after birth, analysis was performed on newborn (P0) mice. Results: Compared to those of Mstn-/- mice, cranial bone volume, thickness, and mineral density levels were all significantly diminished in Gdf11-/- mice. Tissue mineral density of Gdf11-/- mice were also significantly decreased compared to wild-type mice. Likewise, lower incisor length, tissue volume, thickness, and mineral density levels were all significantly reduced in Gdf11-/- mice compared to Mstn-/- mice. Incisor length was also significantly decreased in Gdf11-/- mice compared to wild-type mice. Mstn-/- mice exhibited mildly increased levels of tissue volume, thickness, and density in cranial bone and lower incisor compared to wild-type mice although statistically not significant. Conclusions: Our findings suggest that GDF11, unlike MSTN, endogenously promotes cranial bone and tooth development.

• The Korean Journal of Mycology
• /
• v.27 no.1 s.88
• /
• pp.1-9
• /
• 1999

For the practical using of liquid spawn we carried out selection test of nutrient sources, cultural methods and cultural apparatus for liquid spawn production of oyster mushroom(ASTI 2001, ASTI 2018, ASTI 2072, ASTI 2016, ASTI 2070, ASTI 2180, ASTI 2183, ASTI 2042). The optimal temperature and pH range for mycelial growth of Pleurotus species were $25^{\circ}C\;to\;30^{\circ}C$ and 5.5 to 6.5, respectively. The effect of carbon sources, nitrogen sources and mineral salts on the mycelial growth was studied using petridish culture. Generally, the disaccharides and polysaccharides showed good effect for mycelial growth of Pleurotus species, and the polysaccharides were superior to the other classes of carbon sources for mycelial growth. For the mycelial growth of the 8 oyster mushroom stains, soybean flour was superior to the other kinds of nitrogen sources. On the other hand, addition of mineral salts did not affect, and even poor under certain mineral salts, the mycelial growth of the 8 oyster mushroom stains. The brown sugar selected out the carbon source of the agricultural medium. Also the soybean flour selected out the nitrogen source of agricultural medium. In the medium selection, we selected out agricultural optimum medium composed of brown sugar 3%, soybean flour 0.3%, potassium phosphate 0.05%, magnesium sulfate 0.05%. Under the 250 ml erlenmeyer culture, the effects of such factors as the inoculum rate, the working volume, cultural method and flask shapes on the mycelial growth were examined. The optimal inoculum rate and working volume on the mycelial growth of oyster mushroom was 2 mycelial disk (diameter 6 mm) and 100 ml, respectively. The shake flask culture was enhanced the mycelial growth than at the erlenmeyer flask. Pulp form growth of mycelium in the erlenmeyer flask culture was obtained in the culture with glass rod of length 50 mm, diameter 10 mm.

• Tuberculosis and Respiratory Diseases
• /
• v.45 no.2
• /
• pp.416-420
• /
• 1998

Flow-volume loop is known to be useful in the diagnosis of upper airway obstruction. In cases of tracheal obstruction, characteristic features such as fixed or variable upper airway obstruction patterns give clue to the diagnosis. But the flow-volume loop of unilateral mainstem bronchial stenosis is not known well. There is controversy in patterns of flow-volume loop in unilateral mainstem bronchial stenosis (restrictive pattern or biphasic pattern). We report a case of biphasic flow-volume loop in left mainstem bronchial stenosis(4-5 mm in diameter) as a sequela of endobronchial tuberculosis, which recovered normal flow-volume loop after metallic stent insertion and 2 months later showed reappearance of biphasic pattern because of restenosis of left mainstem bronchus due to growth of granulation tissue at the stent site.