• Geomechanics and Engineering
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• 제28권6호
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• pp.547-557
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• 2022

Dune sands are poorly graded collapsible soils lacking fines. This experimental study explored the technical feasibility of sustainable invigoration of fine waste materials to improve the geotechnical properties of dune sand. The fine waste considered in this study is fine marble waste. The fine waste powder was mixed with dune sand at different contents (5, 10,15, 20, 25, 50%), where the gradation, void ratio, compaction, and shear strength characteristics were assessed for each fine marble waste -dune sand blend. The geotechnical properties of the dune sand-fine marble waste mix delineated in this study reveal the enhancement in compaction and gradation characteristics of dune sand. According to the results, the binary mixture of dune sand with 20% of fine marble waste gives the highest maximum dry density and results in shear strength improvement. In addition, a numerical study is conducted for the practical application of the binary mix in the field and tested for an isolated shallow foundation. The elemental analysis of the fine marble waste confirms that the material is non-contaminated and can be employed for engineering applications. Furthermore, the numerical study elucidated that the shallow surface replacement of the site with the dune sand mixed with 20% fine marble waste gives optimal performance in terms of stress generation and settlement behavior of an isolated footing. For a sustainable mechanical performance of the fine marble waste mixed sand, an optimum dose of 20% fine marble waste is recommended, and some correlations are proposed. Thus, for improving dune sand's geotechnical characteristics, the addition of fine marble waste to the dune sand is an environment-friendly solution.

• 호남수학학술지
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• 제33권4호
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• pp.453-465
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• 2011

Lim et al. [5] introduce the notion of ordinary smooth topologies by considering the gradation of openness[resp. closedness] of ordinary subsets of X. In this paper, we study a collection of all ordinary smooth topologies on X, say OST(X), in the sense of a lattice. And we prove that OST(X) is a complete lattice.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.836-841
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• 2004

This paper describes ASIC design for brightness revision control, A LED Pixel Matrix (LPM) design and LPM in natural color LED vision. A designed chip has 256 levels of gradation correspond to each Red, Green, Blue LED pixel respectively, which have received 8bit image data. In order to maintain color uniformity by reducing the original rank error of LED, we adjusted the specific character value 'a' and brightness revision value 'b' to pixel unit, module unit and LED vision respectively by brightness characteristic function with 'Y=aX+b'. In this paper, if designed custom chip and brightness revision control method are applied to manufacturing of natural color LED vision, we can obtain good quality of image. Furthermore, it may decrease the cost for manufacturing LED vision or installing the plants.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.517-520
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• 2005

In this paper, we propose a motion picture processor for CSTN-LCD without gamut problem. The proposed method employed CDF(Cumulative Density Function) in order to perform a mutual independent in image gradation and color balance. In addition, the proposed method has solved a gamut problem used by conversion of RGB system and CMY system. Also, we apply the BFI (Black Field Insertion) to the design to compensate for response time of a LC (Liquid Crystal). The proposed hardware architecture has been implemented and verified using a FPGA on prototype board. Visual test and standard deviation of histogram were introduced to evaluate the result of the proposed method and the original ones.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.113-114
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• 2015

This paper is to investigate the effect of poor quality aggregate source used in Korea on the mixture proportion and strength development of the high strength concrete fixed at 450 kg/m3 of cement contents. For aggregate kinds, good quality crushed stone from KS certified manufacturer and low quality crushed stone from non certified construction field are used. For fine aggregates, river sand, land sand, sea sand and mixed sand are also used. It is found that the use of low quality aggregates resulted in an increase of water demand considerably due to poor gradation of aggregate and excessive fine particles. Test results indicate that the use of low quality aggregate also decreases the compressive strength compared with that of good quality aggregate.

• 한국의류학회지
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• 제21권1호
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• pp.194-205
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• 1997

The typical instrumental assessment of ununiform natural soils has been carried out by yellowing of the specimens instead of the surface reflectance or the calculated formula. However, the regular instrumental area of sample holder is necessary for the measure of yellowing. Therefore, this study attempted to apply image analysis which had full color image by scanning of one time without limitation of instrumental area. The test samples were analyzed pseudo and full color image. This paper evaluated soil with hue of yellowing and gradation of gray level with color image analysis. Then, it was studied propriety of image analysis with correlation of yellowing, hue and gray level. Ultimately, the proposed image analysis in this paper was advanced method against the typical instrumental assessment.

• 한국식품영양학회지
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• 제22권4호
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• pp.587-597
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• 2009

Peeled chestnuts were stored at different temperatures($-10^{\circ}C$ and $-20^{\circ}C$) and after blanching at $90^{\circ}C$ for different lengths of time(0, 10, and 20 min) for 6 months. After the storage period, the texture, color, DSC and sensory characteristics were analyzed. Hardness, fracturability and chewiness increased with storage time, whereas springiness and cohesiveness decreased. Additionally, the L* decreased and a* and b* increased with storage time. Analysis of the DSC revealed that the peak of the retro gradation was approximately $46{\sim}60^{\circ}C$ and enthalpy for the peak increased with storage time. Additionally, the increment of enthalpy for samples stored at $-20^{\circ}C$ and blanched was lower than that of samples stored at $-10^{\circ}C$ and non-blanched samples. The sensory evaluation scores were also higher for samples stored at $-20^{\circ}C$ and blanched samples than for those stored at $10^{\circ}C$ and non-blanched samples.

• 한국안전학회지
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• 제16권1호
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• pp.65-72
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• 2001

Portland cement concrete is made with coarse aggregate, fine aggregate, portland cement, water and, in some cases, selected chemical admixture such as air-entraining agents, water reducer, superplasticizer, and so on, and mineral admixture such as fly ash, silica fume, slags, etc. Typically, in the concrete, the coarse aggregate and fine aggregate will occupy approximately 80 percent of the total volume of the finished mixture. Therefore, the coarse and fine aggregates affect to the properties of the portland cement concrete. As the deposits of natural sands have slowly been depleted, it has become necessary and economical to produce crushed sand(manufactured fine aggregate). It is reported that crushed sand differs from natural sands in gradation, particle shape and texture, and that the content of micro fines in the crushed sand affect to the quality of the portland cement concrete. Therefore, the purpose of this paper is to investigate the characteristics of fresh and hardened concrete with higher micro fines. This study provides a firm data to apply crushed sand with higher micro fines.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.73-78
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• 2001

Portland cement concrete is made with coarse aggregate, fine aggregate, portland cement, water and, in some cases, selected chemical admixtures such as air-entraining agents, water reducer, superplasticizer, and so on, and mineral admixtures such as fly ash, silica fume, slags, etc. Typically, in the concrete, the coarse aggregate and fine aggregate will occupy approximately 80 percent of the total volume of the final mix. Therefore, the coarse and fine aggregates affect to the properties of the portland cement concrete. As the natural sands are drained, it is necessary and economical to utilize crushed sands(manufactured fine aggregate). It is reported that crushed sands differ from natural sands in gradation, particle shape and texture, and the micro fines in the crushed sands affect to the quality of the portland cement concrete. Therefore, the purpose of this paper is to investigate the characteristics of fresh and hardened concrete with high content of micro fines. This study provides firm data for the use of crushed sands with higher micro fines.

• 한국세라믹학회지
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• 제35권3호
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• pp.251-258
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• 1998

박슬라브 연주용 침지노즐 슬래그 라인부위의 ZrO2-C의 사용중 거동을 조사한 결과 지르코니아 골재의 탈안정화에 의한 조직열화는 예열단계에서 거의 완료되고 사용된 원료의 순도 및 첨가제인 금속 Si의 함량에 의해 크게 좌우되었다. 주조중에는 예열단계에서 발생된 입계로 몰드 파우더로부터 환원된 성분이 축적되어 입계가 더욱 넓어지면서 조직열화가 심화되었으나 환원성분에 의한 추가적인 지르코니아의 탈안정화 현상은 거의 발생되지 않았다.