• 제목/요약/키워드: effective gravity

검색결과 329건 처리시간 0.031초

IGRINS Spectral Library

  • Park, Sunkyung;Lee, Jeong-Eun;Kang, Wonseok;Lee, Sang-Gak;Chun, Moo-Young;Kim, Kang-Min;Yuk, In-Soo;Lee, Jae-Joon;Mace, Gregory N.;Kim, Hwihyun;Kaplan, Kyle F.;Jaffe, Daniel T.
    • 천문학회보
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    • 제41권2호
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    • pp.43.3-43.3
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    • 2016
  • We present a library of high-resolution (R~45,000) and high signal-to-noise ratio ($S/N{\geq}200$) near-infrared spectra of 147 standard stars. High quality spectra were obtained with Immersion GRating INfrared Spectrograph (IGRINS) covering the full range of H ($1.496-1.795{\mu}m$) and K ($2.080-2.460{\mu}m$) bands. The targets are mainly selected as MK standard stars which have well-defined spectral types and luminosity classes, and cover a wide range of effective temperatures and surface gravities. The spectra were corrected for telluric absorption lines and absolute flux calibrated using Two Micron All Sky Survey (2MASS) photometry. We find new spectral indices in H and K bands and provide their EWs. We describe empirical relations between the measured EWs and stellar atmosphere parameters such as effective temperature and surface gravity.

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고정밀 저비용 퍼지 제어기(I)-VHDL 설계 및 시뮬레이션 (An accurate and cost-effective fuzzy logic controller(I)-A VHDL design and simulation)

  • 김대진;조현인
    • 전자공학회논문지C
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    • 제34C권7호
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    • pp.38-50
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    • 1997
  • This paper concerns a VHDL design and simulation of an accurate and cost-effective fuzzy logic controller (FLC). The accurcy of the proposed FLC is obtained by using the center of gravity (COG) defuzzifier that considers both membership values and spans of membership functions in calculating a crisp value. The cost-effectiveness of the proposed FLC is obtained by restructuring the conventional FLC in the following ways: Firstly, the MAX-MIN inference is inference is replaced by a read-modify-write operation that can be implemented economically in the structure of register files. Secondly, the division in the COG defuzzifier is avoided by finding the moment equilibrium point. The proposed COG defuzzifier has two disadvantages that it requires additional multipliers and it takes a lot of computation time to find the moment equilibrium point. The first disadvantage is overcome by replacing the mulitpliers with stochastic AND operations and the second disadvantage is alleviated by using a coarse-to-fine searching algorithm. The proposed FLC is described in VHDL structurally and behaviorally and whether it is working well or not is checked on SYNOPSYS VHDL simulator by using the truck backer-upper control problem.

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Oil과 Modified Styrene을 사용(使用)한 미립(微粒) 무연탄(無煙炭)의 응집(凝集) (Agglomeration of fine anthracite using oil and modified styrene)

  • 이재장;장동성
    • 산업기술연구
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    • 제7권
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    • pp.27-47
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    • 1987
  • Fine anthracite is very difficult to upgrade by conventional processes such as gravity concentration or froth flotation, because large quantities of fine coals are generated at the mining and preparation stages and a significant portion of these fine coals are mixed with gangue minerals. This study, therefore, was carried out for the purpose of improving recovery of low ash clean coal, effective beneficiation of low-grade coking coal and removal of sulphur from high-sulphur coals by employing the method of selective agglomeration using oil or polystrene flocculants, for coals which are generally hydrophobic in nature will be extracted by using flocculants. Studies were performed by varying solid concentration, concetration of bridging liquid, mixing speed and mixing time, balling speed and balling time, dispersant dosage, flocculant dosage, pulp pH, and particle size. The results were : when the methods of the oil agglomeration and selective flocculation were employ(in the two process the sample was ground to the size of -74 micron), 1) ash content of the agglomerated coal was 9.85, 7.83%, 2) combustibel recovery of it was 98.5%, 93.5%, respectively. It was observed in selective flocculation that polystyrene is an effective flocculant for coal, De-entrapment of shale from the concentrate flocculated by mechanical agitation was necessary for substantional reductions in final ash content.

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경락 마사지가 뇌성마비장애인의 근력, 관절운동범위 및 일상생활활동에 미치는 영향 (The Effect of Meridian Massage on Muscle Power, ROM, and ADL in Persons with Cerebral Palsy)

  • 오미정;최경희
    • 기본간호학회지
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    • 제10권1호
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    • pp.68-77
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    • 2003
  • Purpose: This study analyzed the effects of meridian massage on the muscle power, ROM, and ADL in persons with cerebral palsy. Method: A non-equivalent pre-test/post-test design was used. The data were collected from August to October, 2000 from 10 persons with cerebral palsy (a control group of 5 and an experimental group of 5). Muscle power was evaluated with the Brunnstrom-Dennen gravity test, ROM with a goniometer, and ADL with a self developed ADL scale. T-test, repeated measure ANOVA were used for statistical analysis. Result: The results are; 1. For muscle power, both time series group difference (F=10.66, p=0.000) and the total period group difference (F=72.67, p=0.000) were significant between the two groups. 2. ROM was not significantly different between the two groups. 3. For ADL, both time series group difference (F=7.09, p=0.001) and total period group difference (F=35.99, p=0.000) were significant between the two groups. Conclusion: Overall, this study shows that Meridian massage is effective for muscle power, ROM, and ADL in persons with cerebral palsy person. So it can be used to develope effective nursing programs to improve the function of motion of persons with cerebral palsy.

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기둥으로 지지된 슬래브교(橋)의 모멘트 산정(算定)에 관한 연구(硏究) (Simplified Bending Moment Analysis in Slab Bridges supported by Column Type Piers)

  • 김영인;이채규;김우
    • 대한토목학회논문집
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    • 제12권3호
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    • pp.17-24
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    • 1992
  • 철근(鐵筋)콘크리트 슬래브교(橋) 설계시(設計時) 교각(橋脚)을 T형 및 ${\Pi}$형식으로 취하는 것보다 기둥만으로 슬래브를 직접 지지(支持)하도록 함으로써 유효공간(有效空間) 확보 뿐만 아니라 슬래브 자체(自體)의 내하력(耐荷力)을 이용함으로써 구조적(構造的)인 효율측면(效率側面)에도 유리하다. 그러나 기둥으로 지지된 슬래브교의 설계를 위한 휨모멘트계산은 아직 체계화(體系化)되어 있지 않은 상태이다. 중간지지점(中間支持點)의 종방향(縱方向) 최대휨모멘트를 유효폭개념(有效幅槪念)을 적용하여 가상지간(假像支間)을 이용한 단순보해석으로 간단히 구할 수 있는 방법(方法)에 대하여 연구하고 유효폭을 수식화(數式化)하였다. 주요변수(主要變數)는 지간(支間), 교폭(橋幅), 슬래브 두께 및 기둥단면(斷面)으로 하고 유한요소법(有限要素法)을 이용하여 단면력(斷面力)의 변화를 조사하였다.

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메쉬 여과모듈을 이용한 잉여슬러지 농축 (Thickening of Excess Sludge using Mesh Filter)

  • 정용준;키소 요시아키;민경석
    • 한국물환경학회지
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    • 제20권4호
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    • pp.346-351
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    • 2004
  • Because of being produced a great deal of excess sludges from biological wastewater treatment process, the subject regarding treatment and disposal of them has been significantly handled in real plants. It should be considered the alternative treatment with easy operating and cost effective process in rural areas. For the thickening of wasted activated sludge from small scale wastewater treatment facilities, thus, the provisional sludge thickening system was developed by the application of mesh filter module. Three meshes with different pore size(100, 150, $200{\mu}m$) were prepared for filter modules that were used to withdraw effluent from thickening system. A filter module with $100{\mu}m$ mesh was chosen as the most effective thickening material in the viewpoint of volume reduction and effluent quality: the volume reductions of initially injected sludge with 3,600 mg/L and 9,100 mg/L were 95% and 85%, respectively, and the filtered effluents were enough good to be shown below 1.0 mg/L of SS and 1.0 NTU of turbidity. Since the filtration of thickening was influenced by the cake layer formed on mesh filter module and this system was operated in the combination of sludge thickening with gravity settling, the filter modules with smaller pore size and the larger floc size were required for long term operation safely.

식이섬유, 효소 및 달걀 첨가 수준에 따른 쌀빵의 제빵 적성 및 품질 특성 (Characteristics of Bread-making and Quality of Rice Bread with Different Percentages of Dietary Fiber, Enzymes and Egg)

  • 김상숙;정혜영
    • 한국식생활문화학회지
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    • 제33권6호
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    • pp.580-587
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    • 2018
  • The baking properties of rice bread with polydextrose (3, 6, and 9%), enzymes (0.006, 0.009, and 0.018%) and egg (1.32 and 2.64%) were investigated. The specific gravity and color (L, a, b) of the dough, as well as the appearance, color (L, a, b) and texture of the rice bread were analyzed. The springiness, chewiness, gumminess (p<0.01) and hardness (p<0.001) of the rice bread tended to increase as the amount of added polydextrose increased. Replacement of rice flour with hemicellulase, glucose oxidase and fungal amylase are effective for producing rice bread. Replacement of rice flour with 0.009% glucose oxidase and 0.006% fungal amylase had a significant effect on increasing the volume and decreasing the hardness of the rice bread (p<0.001). Replacement of rice flour with 1.32% egg white also had a significant effect on increasing the volume and decreasing the hardness of the rice bread (p<0.001). These results suggest that replacement of rice flour with 0.009% glucose oxidase and 0.006% fungal amylase, and 1.32% egg white are effective for producing rice bread with good volume and hardness.

등가선형해석이론에 의한 소방설비 구성품의 Lab scale 내진성능평가기법 개발 (Development of a Seismic Test Method for Fire Protecting Components by Equivalent Linear Analysis Theory)

  • 곽지현;윤종구
    • 한국화재소방학회논문지
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    • 제27권1호
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    • pp.46-51
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    • 2013
  • 지진 발생 시 건물에 설치된 소방설비 주요 구성품의 내진성능을 평가할 수 있는 실험실에서 수행 가능한 Lab scale의 내진성능시험방법을 개발하기 위하여 지반응답해석방법과 전달함수 등을 바탕으로 한 등가선형해석이론을 적용하고자 하였다. 내진성능시험은 등가가속도에 의한 시험과 임의가속도에 의한 시험으로 나눠지는데, 등가가속도 시험은 등가선형해석에 의해 지진 규모에 따른 등가가속도를 적용하여 공진점을 찾거나 시험체의 이상 유무를 관찰하는 것이며, 임의가속도 시험은 순간적인 강진이 가해질 때를 모사한 것으로 가진주파수와 가진폭에 따라 가속도가 결정되며 기능수행여부 또는 물리적 손상 등을 확인할 수 있다. 본 연구에서 개발한 시험방법을 수계소화설비 주요 구성품에 적용한 결과 특등급에 해당하는 강진 발생 시 기능수행여부를 확인할 수 있었으며, 이러한 시험방법을 통해 소방설비 구성품에 대한 내진성능을 검증할 수 있을 것으로 기대된다.

입자상 물질의 습성 침적에 관한 수치 모의 (The Numerical Simulation on the Wet Deposition of Particles)

  • 김유근;이화운;홍정혜
    • 한국대기환경학회지
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    • 제14권5호
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    • pp.433-442
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    • 1998
  • The removal procedure of particles in the atmosphere was simulated in the saturated and dry conditions to know the effect of the saturated atmosphere on the size distributions of particles. The particles were divided into 5 ranges, 0.0mm, 0.0∼0.65mm, 0.65∼2mm, 2∼10mm and more than 10mm, and the gases were classified into the smallest range for calculation. At the dry condition, particles grew only by the collision -coalescence and were removed by gravitation. The particles in the range of 2.0∼10mm fell mostly at the 30 km distance from the pollutant source because of gravitation. The particles larger than 10 pm were removed at the 10 km distance from the pollutant source because of their gravity. But the particles larger than 10pm appeared again at more than 30km distance. It is considered that they have been grown during the smaller particles had been advected and diffused at that distance, and it needed about 1 hour from the moment of release. At the saturated condition, particles grew by both the collision-coalescence and condensation. The model showed that the condensation makes more number of particles larger than 10mm and then the particles were removed due to their large gravity. Only a few particles existed at the range of 0.65∼10mm and larger thats 10mm. It is concluded that the saturated atmosphere is effective on removing PM-10.

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중력 여과장치 이용 미세조류 수확을 위한 여과막의 효율성 비교 (Comparison of Filtration Efficiency of Membranes for Harvesting Microalgae using a Gravity-Filtration Device)

  • 신동우;조용희;김기현;김한별;박한울;김지훈;임상민;이철균
    • 한국해양바이오학회지
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    • 제9권1호
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    • pp.8-13
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    • 2017
  • Cost-effective microalgae harvesting methods are necessary for economical production of algal biodiesel. In this study, membranes with various pore sizes and materials were examined for their potentials in application to gravity-filtration of Tetraselmis sp. KCTC12432BP. For this test, 10 L of Tetraselmis sp. culture (2 g/L) was loaded on each membrane and filtration rates were measured. Among the tested materials, a woven cotton fabric showed the fastest water drain rate (0.73 L/hr) without serious cell leakage. Cell density of the concentrates after filtration was 6.8 g/L, indicating 3.4-fold concentration compared with the initial algal culture. The result suggests that the woven cotton fabric could serve as filtration membrane for harvesting Tetraselmis sp. among the tested ones.