• Title/Summary/Keyword: Mineral Characteristics

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A Experimental Study on the Physical properties of Lightweight Foamed Concrete Using Mineral Foam Agent (광물성 기포제를 이용한 경량기포콘크리트의 물리적성질에 관한 실험적 연구)

  • 유제준;이한승;배규웅;이상섭;연규봉
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2003.05a
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    • pp.49.1-52
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    • 2003
  • The objective of this study the mechanical characteristics of preformed lightweight foamed concrete using the mineral foam agent which has high lightness, and strength. The compressive strength of lightweight foamed concrete using mineral foam agent are about 2 times degree high those the of lightweight foamed concrete using vegetable foam agent. Lightweight foamed concrete was able to obtain the result of 50kg/$\textrm{m}^3$ or more compressive strength, when was unit weight 0.8t/$\textrm{m}^3$. In the can of the same unit weight of concrete, it is influenced by w/c of loan agent ratio. The paper present extensive data on characteristics of compressive strength of the concrete manufactured with the different factors in mix design and also present optimum mix proportion.

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Countermeasure of rebound reducing for wet-mixed steel fiber reinforced shotcrete (강섬유보강 습식 숏크리트의 리바운드 저감대책)

  • Lim Joo-Young;Park Hae-Geun;Lee Myeong-Sub;Cho Nam-Sup
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.1162-1167
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    • 2004
  • From the early 1980's, the New Austrian Tunnelling Method (NATM) has been developed as a one of the standard tunneling method in Korea. Owing to the results of many researches, the practical problems of shotcrete has been improved for a last decade. However, the excess amount of rebound still remains one of the critical problems in shotcrete technology. In order to improve for this rebound problem, recently developed cement mineral accelerator has been successfully applied to several NATM tunnels in Korea. An experimental investigation was carried out in order to verify the rebound characteristics of wet-mix Steel Fiber Reinforced Shotcrete (SFRS) with powder types cement mineral accelerator. Mortar setting test, SEM analysis, bonding test under spring water condition and rebound test were conducted. From the result, wet-mix SFRS with cement mineral acelerator exhibited excellent bonding characteristics even spring water condition and less rebound ratio compared to the conventional liquid accelerator.

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Correlation between Nutrient Intakes and Bone Mineral Density in Carpus of Female University Students (일부 여대생의 영양섭취와 손목 골밀도와의 상관성)

  • Choe, Yu-Jin;Im, Rut;Ra, Seon-Hwa;Choe, Mi-Gyeong
    • Journal of the Korean Dietetic Association
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    • v.12 no.1
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    • pp.10-17
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    • 2006
  • The purpose of this study was to examine the correlation between nutrient intakes and bone mineral density in female university students. A total 27 female university students were measured the anthropometric characteristics, dietary intake and the bone mineral density of carpus using DEXA. The average age, height, weight, % body fat, WHR, and BMI of the subjects were 22.7 years, 161.5 cm, 57.0 kg, 29.9%, 0.8, 21.8 kg/$m^2$, respectively. Bone mineral density of ultradis and distal carpus as T-value were -1.5 and -0.4, respectively. The daily energy intake of the subjects was 1589.0kcal. And the intakes of energy, calcium, iron, zinc, vitamin $B_2$, and folic acid did not meet the Korean RDAs. The daily total food intake of the subjects was 1011.0g and food intake from cereals and vegetables was high. The major food groups of mineral intake were vegetables/cereals/milks/fishes for calcium, cereals/meat/vegetables/fishes for phosphorus, cereals/vegetables/meats for iron, seasonings/vegetables/cereals for sodium, vegetables/cereals/seasonings for potassium, and cereals/meats for zinc. The body weight and body mass index were significantly positive correlated to the bone mineral density of average carpus, respectively. The intakes of animal calcium and vitamin $B_2$ were significantly negative correlated to the bone mineral density of average carpus, respectively. In conclusion, bone mineral density in carpus and nutrient intakes of some female university students were low. Therefore, health management and the study on relation between bone mineral density in various site and long-term intakes of nutrients in many subjects are required.

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Evaluation of TDF ash as a Mineral Filler in Asphalt Concrete (TDF ash를 채움재로 사용한 아스팔트 콘크리트 물성 평가)

  • Choi, MinJu;Lee, JaeJun;Kim, HyeokJung
    • International Journal of Highway Engineering
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    • v.18 no.4
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    • pp.29-35
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    • 2016
  • PURPOSES : The new waste management policy of South Korea encourages the recycling of waste materials. One material being recycled currently is tire-derived fuel (TDF) ash. TDF is composed of shredded scrap tires and is used as fuel in power plants and industrials plants, resulting in TDF ash, which has a chemical composition similar to that of the fly ash produced from coal. The purpose of this study was to evaluate the properties of an asphalt concrete mix that used TDF ash as the mineral filler. METHODS : The properties of the asphalt concrete were evaluated for different mineral filler types and contents using various measurement techniques. The fundamental physical properties of the asphalt concrete specimens such as their gradation and antistripping characteristics were measured in accordance with the KS F 3501 standard. The Marshall stability test was performed to measure the maximum load that could be supported by the specimens. The wheel tracking test was used to evaluate the rutting resistance. To investigate the moisture susceptibility of the specimens, dynamic immersion and tensile strength ratio (TSR) measurements were performed. RESULTS : The test results showed that the asphalt concrete containing TDF ash satisfied all the criteria listed in the Guide for Production and Construction of Asphalt Mixtures (Ministry of Land, Infrastructure and Transport, South Korea). In addition, TDF ash exhibited better performance than that of portland cement. The Marshall stability of the asphalt concrete with TDF ash was higher than 7500 N. Further, its dynamic stability was also higher than that listed in the guide. The results of the dynamic water immersion and the TSR showed that TDF ash shows better moisture resistance than does portland cement. CONCLUSIONS : TDF ash can be effectively recycled by being used as a mineral filler in asphalt, as it exhibits desirable physical properties. The optimal TDF ash content in asphalt concrete based on this study was determined to be 5%. In future works, the research team will compare the characteristics of asphalt concrete as function of the mineral filler types.

The Effect of Natural Mineral Complex and Chitosan Supplementation on Egg Production and Characteristics in Laying Hens (사료 내 천연 미네랄과 키토산의 수준별 첨가가 산란계의 산란율 및 계란 품질에 미치는 영향)

  • Yoo, J.S.;Kim, J.D.;Cho, J.H.;Chen, Y.J.;Kim, H.J.;Min, B.J.;Kang, D.K.;Kim, I.H.
    • Korean Journal of Poultry Science
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    • v.33 no.4
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    • pp.309-316
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    • 2006
  • This study was conducted to investigate the effects of dietary natural mineral liquid complex on egg production and characteristics in laying hens. A total of two hundreds fifty two, 63-weeks-old, Hy-line brown commercial layers were used for 6 weeks. Seven dietary treatments included CON (Control), C1-M0.25 (CON diet+1% chitosan+0.25% natural mineral complex), C1-M0.5 (CON diet+1% chitosan+0.50% natural mineral complex), C2-M0.25 (CON diet+2% chitosan+0.25% natural mineral complex), C2-M0.50 (CON diet+2% chitosan+0.50% natural mineral complex), C3-M0.25 (CON diet+ 3% chitosan+0.25% natural mineral complex) and C3-M0.50 (CON diet+3% chitosan+0.50% natural mineral complex). For overall period, egg production, egg shall breaking strength, haugh unit, K and Fe concentrations of blood and Fe concentration of yolk were improved in additive natural mineral treatments compared to control treatment(P<0.05). K and Fe concentrations of blood and Fe concentration of yolk were increased in added 0.5% mineral treatment compared to added 0.25% mineral treatment(P<0.05). Additive 3% chitosan + 0.5% mineral treatments were improved on egg Production and egg shall breaking strength in laying hens(P<0.05). In conclusion, chitosan and natural mineral complex supplementation in lay hens diet improved egg oduction, egg all strength and mineral concentrations of blood and yolk.

Preliminary Results of Polarimetric Characteristics for C-band Quad-Polarization GB-SAR Images Using H/A/$\alpha$ Polarimetric Decomposition Theorem

  • Kang, Moon-Kyung;Kim, Kwang-Eun;Lee, Hoon-Yol;Cho, Seong-Jun;Lee, Jae-Hee
    • Korean Journal of Remote Sensing
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    • v.25 no.6
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    • pp.531-546
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    • 2009
  • The main objective of this study is to analyse the polarimetric characteristics of the various terrain targets by ground-based polarimetric SAR system and to confirm the compatible and effective polarimetric analysis method to reveal the polarization properties of different terrain targets by the GB-SAR. The fully polarimetric GB-SAR data with HH, HV, VH, and VV components were focused using the Deramp-FFT (DF) algorithm. The focused GB-SAR images were processed by the H/A/$\alpha$ polarimetric decomposition and the combined H/$\alpha$ or H/A/$\alpha$ and Wishart classification method. The segmented image and distribution graphs in H/$\alpha$ plane using Cloude and Pottier's method showed a reliable result that this quad-polarization GB-SAR data could be useful to classified corresponding scattering mechanism. The H/$\alpha$-Wishart and H/A/$\alpha$-Wishart classification results showed that a natural media and an artificial target were discriminated by the combined classification, in particular, after applying multi-looking and the Lee refined speckle filter.

A Study on Engineering Characteristics of Asphalt Concrete Mixtures Using Filler with Recycled Waste Lime (부산석회를 채움재로 재활용한 아스팔트 혼합물의 공학적 특성)

  • Hwang, Sung-Do;Park, Hee-Mun
    • International Journal of Highway Engineering
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    • v.7 no.3 s.25
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    • pp.71-78
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    • 2005
  • This study focuses on finding out engineering characteristics of asphalt concrete mixtures using mineral fillers with recycled waste lime, which is a by-product in the Soda Ash(Na2CO3) production course. The materials tested in this study were made with 25%, 50%, 75% and 100% of mixing ratio based on the conventional mineral filler ratio to analyze the recycle possibility of the waste lime. The asphalt concrete mixtures with recycled waste lime and hydrated lime, and conventional asphalt concrete mixtures were evaluated through their fundamental engineering properties such as Marshall stability, indirect tensile strength, resilient modulus, permanent deformation characteristics, moisture susceptibility and fatigue resistance. The results indicate that the application of recycled waste lime as mineral filler improves the permanent deformation characteristics, stiffness and fatigue endurance of asphalt concrete mixtures at the wide range of temperatures. It is also found that the mixtures with recycled waste lime show higher resistance against stripping than conventional asphalt concrete mixtures. It is concluded from various test results that the waste lime can be used as mineral fillers and especially can greatly improve resistance to permanent deformation of asphalt concrete mixtures at high temperatures.

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Analysis on the Temperature Distribution Characteristics of Insulating oil of Transformer Using the Vegetable oil and Mineral oil (식물성 절연유와 광유가 사용된 유입변압기의 온도분포 특성)

  • An, Jung-Sik;Shim, Meoung-Seop;Jung, Joong-Il;Kim, Nam-Ryul;Huh, Chang-Su
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.1215_1216
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    • 2009
  • Most transformer use insulating and cooling fluids derived from petroleum crude oil, but mineral oil is some possibility of environmental pollution and fire with explosion. vegetable oil fluids extracted from seed has superior biodegradation and fire-resistant properties including an exceptionally high fire point enhancing fire safety. In this study, it is aimed at the practicality of substituting natural ester dielectric fluid for mineral oil in liquid insulation system of transformers. As a rise in coil winding temperature has a direct influence on transformer life time, it is important to evaluate the temperature rise of coil winding in vegetable oil in comparison with mineral oil. Three transformers for the test are designed with 10KVA, 13.2KV, one phase unit. The temperature are directly measured in insulating oil of these transformers with the two sorts of natural ester and mineral oil dielectric fluid respectively. Temperature of vegetable oil transformers was similar to temperature of mineral oil transformer in the same design at 80% load and above.

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Extraction characteristics of extraction resins containing PC88A (PC88A를 함유한 추출레진의 추출 특성)

  • Park, Kye-Sung;Lee, Jin-Young;Yoon, Ho-Sung;Kim, Chul-Joo;Eom, Hyoung-Choon;Kim, Joon-Soo
    • Proceedings of the Korean Institute of Resources Recycling Conference
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    • 2005.10a
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    • pp.168-172
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    • 2005
  • 동일한 추출제가 함유된 3종의 추출레진을 대상으로 중희토류인 Gd의 추출특성을 비교하였다. 실험조건은 $20^{\circ}C$에서 평형 pH, Gd 농도, 추출시간으로 하여 다음과 같은 결과를 얻었다. 추출레진에서 추출시간 5분이내에 $Gd^{3+}$ 이온이 90%이상 추출되며, 추출시간 30분 이후에 변화가 거의 없어 추출반응이 종결된 것으로 판단된다. 평형 pH. 2.2이하에서 분배비는 평형 pH에 대해 선형적으로 감소하였다. Freundlich's 흡착등온식을 도입하여 3종의 추출레진에 대해 적용해 본 결과 결정계수$(R^2)$ 0.95이상으로 나와, Freundlich's 흡착등온식에 부합됨을 알 수 있었다.

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A Study on a Classification Technique of Natural Mineral Waters by Its Constitution and Physico-Chemical Properties (鑛泉水 理化學的 水質評價 技法 에 관한 연구)

  • Nam, Sang-Ho
    • Journal of Environmental Health Sciences
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    • v.14 no.1
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    • pp.33-38
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    • 1988
  • Natural mineral water is generally quite different from ordinary drinking water due to its original nature and various properties. The complexity of natural mineral water requires, therefore, not only to identify its nature and proper characteristics, but also to classify them by a reasonable scientific basis of comparison. The study was concentrated on a possible classification technique to natural mineral waters by their constitutions and physico-ehemical properties. The classification was carried out by the computation of such numerical parameters as ionic equivalent percentage, electrolytic conductance or mobility, ionic molecular weight, molecular concentration, equivalent conductivity and degree of ionization in consideration of the determinative criteria as follows -particular single element or molecule -major components of natural waters as bicarbonate, sulphate, chloride,caloride, calcium, magnesium, and sodium -moleculat concentration related to blood osmotic pressure -water temperature at emergence from spring -contents of free carbon dioxide (CO2) -pH value of water -total dissolved solids or salts (NaCl) The results obtained proved out to be clearly distinguhhable from ordinary drinking water as far as concern natural mineral water as an example on the subject -simple water -bicarbonate-predominating water -cold spring -carbonated-non gaseous water -weak alkaline water -non saline water Putting these various results together, the sample turned out to be a kind of natural mineral water that can be used as a drinking water if microbiologically safe.

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