• Bulletin of the Korean Chemical Society
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• v.19 no.2
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• pp.174-178
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• 1998

Blowout of NR and SBR vulcanizates was studied using a microwave oven. Rubber vulcanizates with different contents of carbon black (0, 30, 50, 70 phr) and various cure systems (conventional, semi-EV, and EV) were prepared. Unfilled rubber vulcanizates did not exploded by irradiation of microwave, while carbon black-filled ones exploded within 10 min. A blowout time of the carbon black-filled rubber vulcanizate decreases with an increase of the content of carbon black in the vulcanizate. A blowout temperature of the organic additive-extracted vulcanizate is higher than that of the not-extracted one, but the extracted vulcanizate blows out faster than the not-extracted one. A blowout temperature of the overcured vulcanizate is higher than that of the undercured one with the same cure system. Temperatures of unfilled SBR vulcanizates heated by the microwave irradiation are lower than those of unfilled NR ones. The carbon black-filled SBR vulcanizates blow out at higher temperatures than the carbon black-filled NR ones. Blowout times of the carbon black-filled SBR vulcanizates are longer than those of the carbon black-filled NR ones.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.1
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• pp.45-53
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• 2006

Anaerobic black-pigmented bacteria have been implicated in the endodontic infections. This group of microorganisms includes Porphyromonas endodontalis, P. gingivalis, Prevotella intermedia, and Prevotella nigrescens. The organisms display a wide variety of virulence factors that may be pertinent to acute endodontic infections. The aim of this study was to identify P. endodontalis, P. gingivalis, P. intermedia, and P. nigrescens by using the special potency disk test, filter paper spot test, 16S rRNA gene-directed PCR, and API 32A system. Microbial samples were collected from root canals of 33 intact teeth with necrotic pulp and apical periodontitis. Conventional laboratory methods were used to identify the strains of anaerobic black pigmented bacteria. Eighteen out of 33 samples were positive for the growth of black-pigmented bacrteria. Five colonies were cultured from each pure cultured colony from Brucella agar plates. Seventy seven colonies were positive for the growth of black-pigmented bacteria. Thirty three out of 77(42.8%) were identifed as P. nigrescens, 10 out of 77(13%)were P. gingivalis, 6 out of 77(7.8%) were P. endodontalis, 10 out of 77(13%) were P. intermedia. On the contrary the reference strains of P. nigrescens, experimental strains of P. nigrescens were susceptible to kanamycin in the special potency disk test. We concluded that after rapid presumptive identification methods, such as the special potency disk test and filter paper spot test were done, 16S rRNA gene PCR and API 32A test would be accurate detection methods for black-pigemented bacteria.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1322-1325
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• 2009

Adaptive black band insertion improve blur phenomenon that caused by hold type issue of LCD, the approach regulate charge time by OE signal to control black inserted ratio, and the charge time be modified according the motion quantity of displaying content.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.215-219
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• 2001

Impurities removal from waste carbon black was carried out to produce high-grade carbon black. A lot of hydrophilic carbon black is produced as a byproduct of the hydrogen production process by flame decomposition of water. Due to its impurity content such as sulphur, iron, ash and etc., it can only be used as low-grade carbon or burnt out. High-grade hydrophilic carbon black is 3-5 times more expensive than oil-based carbon black because of its process difficulties and requires pollutant treatment. Hydrophilic carbon is normally used far conductive materials for batteries, pigment for plastics, electric wire covering, additives for rubber, etc.. In these applications, hydrophilic carbon must maintain its high purity. In this study magnetic separation, froth flotation and ultrasonic treatment were employed to remove impurities from the low-grade hydrophilic carbon black. As results, the ash, iron and sulphur content of product decreased to less than 0.01wt.%, 0.0lwt.% and 0.3wt.% respectively, and the surface area of product was about 930 $m^2$/g.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.118-125
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• 1978

To find out highly resistant gene source to black rot fungus in sweetpotato varieties, a screening test was carried out with inoculated tubers and sprouts in 1976 and 1977. Fifteen varieties out of 165 and 54 varieties out of 161 were highly resistant to black rot in the tuber and sprout tests. respectively. The sprout test showed bigger variation from year to year compared to tuber test. Varieties highly resistant to black rot in both tuber and sprout tests were Suweon # 59, #81, #90, Norin #17, #23. Chilship-il cho, Sachun Jong #36, Hamkao, and Kandee.

• Journal of Advanced Navigation Technology
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• v.27 no.6
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• pp.865-870
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• 2023

Recently, accidents caused by black ice, a road freezing phenomenon caused by natural power, are increasing. Black ice is difficult to identify directly with the human eye and is more likely to misunderstand it as standing water, so there is a high accident rate caused by car sliding. To solve this problem, this paper presents a method of detecting black ice centered on LiDAR sensors. With a small, inexpensive, and high-accuracy light detection and ranging (LiDAR) sensor, the temperature and inclination angle are set differently to detect black ice and asphalt by setting different reflection angles of asphalt and black ice differently in temperatures and inclinations. The LIDARO carried out in the study points out that additional research and improvement are needed to increase accuracy, and through this, more reliable black ice detection methods can be suggested. This method suggests a method of detecting black ice through early system design research by preventing accidents caused by black ice in advance.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.6
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• pp.139-144
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• 2019

For recent decades, Non-volatile Memory (NVM) technologies have been drawing a high attention both in industry and academia due to its high density and short latency comparable to that of DRAM. However, NVM devices has write endurance problem and thus the current data structures that have been built around DRAM-specific features including unlimited program cycles is inadequate for NVM, reducing the device lifetime significantly. In this paper, we revisit a red-black tree extensively adopted for data indexing across a wide range of applications, and make it to better fit for NVM. Specifically, we observe that the conventional red-black tree wears out the specific location of memory because of its rebalancing operation to ensure fast access time over a whole dataset. However, this rebalancing operation frequently updates the long-lived nodes, which leads to the skewed wear out across the NVM cells. To resolve this problem, we present a new swapping wear-leveling red-black tree that periodically moves data in the worn-out node into the young node. The performance study with real-world traces demonstrates the proposed red-black tree reduces the standard deviation of the write count across nodes by up to 12.5%.

• Journal of Korean Society for Quality Management
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• v.49 no.3
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• pp.433-446
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• 2021

Purpose: The main purpose of this study is to analyze the case of the transparent PET bottle resource circulation project of BYN Black Yak Co., Ltd., present implications, and propose ways to spread it in the future. Methods: In this study, the logic of the Double Diamond Model is applied to analyze the development process of sustainable fashion made from BYN Black Yak Co., Ltd.'s PET Bottle Resource Circulation System. Results: The K-rPET Resource Circulation Project of BYN Black Yak Co., Ltd. is recognized as a best example for its contribution to eco-friendly activities, solving social problems, raising consumer awareness, and sharing recycling habits. Before the plastic bottle becomes a garment, five steps are taken (discharge of PET bottle → collection of PET bottle → recycling of PET bottle → fabrication of yarn → production of the finished product out of the fabric). BYN Black Yak Co., Ltd. has successfully commercialized it by recycling reverse-recovery PET bottles by making solutions to problems that have not been solved at each stage. Conclusion: In addition to efforts to find and strengthen weak links presented in the Theory of Constrains (TOC), it appears to have systematically carried out activities to convert stakeholder discomforts into a package of gain points. As shown in the slogan "We are all in!" the proposal and implementation for the completion of a true environmental system is judged to have truly performed ESG management well for the company's business. ESG management activities at BYN Black Yak Co., Ltd. are expected to continue.

• Carbon letters
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• v.2 no.3_4
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• pp.165-169
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• 2001

Modification of C/C composite bipolar plate for improving electrical conductivity was carried out by addition of electroconductive carbon black (EC-CB). Carbon black was carefully mixed to methanol-containing phenolic resin, impregnated into 2D-carbon fabrics, hot pressed and then carbonized to obtain composite plate. Inclusion of electro-conductive carbon black enhanced the electrical conductivity of the C/C composites by increasing the conduction path. Addition of 10 vol% carbon black increased the electrical conductivity from 5.5/${\Omega}cm$ to 32/${\Omega}cm$ and reduced the crack formation by filling effect, resulting in the increase of flexural properties of composite plate. However, at carbon black content over 10 vol%, flexural properties decreased by delaminating role of excess carbon black at the interface in C/C composites.

• Textile Coloration and Finishing
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• v.29 no.4
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• pp.276-283
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• 2017

The aim of this study is to develop an effective dyeing process for black color on the silk fabrics, using natural Indigo, Madder, Amur cork tree, Alder, Logwood, and Gallnut. All natural dye materials were water-extracted, concentrated, and freeze-dried. Seven different processes were carried out and the color differences(${\Delta}E$) of black color with each process from the chemical black dyed fabric were compared. The light, washing, and rubbing fastness were evaluated. The black dyeing of the silk fabrics was well carried and excellent black color was obtained in every methods. The profound black color could be obtained by the subtractive mixture of the three primary colors of red, yellow, and blue in the order of indigo(blue) - amur cork tree(yellow) - madder or lac(red). Black color was efficiently obtained by iron mordant when logwood or alder fruit was used. The color difference(${\Delta}E$) from the black color with chemical dyestuff was the lowest in the indigo - amur cork tree - lac - iron method. Light fastness and washing fastness were excellent in all dyeing processes, showing grade 5. The fastness to rubbing was excellent as shown grade 5 in the dry samples of logwood - iron process and alder fruit - iron process.