• 제목/요약/키워드: Mass balance

검색결과 932건 처리시간 0.025초

목재의 연소 특성(2)(연소형태와 연소특성) (Combustion Characteristics of Wood Chips(Flame Shape of Combustion and Ignition Delay))

  • 김춘중;아라이 마사타카;강경구
    • 한국산업융합학회 논문집
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    • 제2권2호
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    • pp.139-146
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    • 1999
  • Combustion Characteristics of the wood chips(balsa chips) were experimental studied as fundamental investigation of the thermal recycle system of the urban dust. The urban dust contains plastics vegetable and lot of wood material. Then, a wood was chosen as an example of the component of urban dust. A small wood chip was burned in a electric furnace and mass reduction rate during volatile and combustion states were recorded by the micro-electric balance and the combustion flame shape took a photograph by video camera at the mass of wood chips and ambient temperature in the furance. Ignition delay took the minimum value when the mass of the test chip was 0.3g. When a mass of the test chip was smaller then 0.001g, combustion with flame did not burnt.

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CHARACTERIZATION OF POOL-RIFFLE SEQUENCES IN SOLUTE TRANSPORT MODELING OF STREAMS

  • Seo, Il-Won;Yu, Dae-young
    • Water Engineering Research
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    • 제1권3호
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    • pp.171-185
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    • 2000
  • A mathematical model to adequately predict complex mixing characteristics of sorptive polluants in natural streams with pools-and-riffes has been developed. In this model, sorption of pollutants onto the bed sediment as well as mass storage and exchange in the storage zones were incorporated into one-dimensional mass balance equatins. The geometric and hydraulic characteristics of the pool-riffle sequences were properly conceptualized. Simulations with parameters of pool-and-riffle streams better fit the measured data in overall shape and peak concentration than simulations with parameters for uniform channels. The analyses on the characteristics of the storage zone model parameters reveal that a linear relationship between the logrithm of the storage zone volume ratio and a function of the friction factor exists. A linear relatiohship might also be tenatively assumed between the logarithm of the dimensionless mass exchange coefficient and the logarithm of the aspect ratio of the storage zone if some of the high values of the dimensionless mass exchange coefficient collected on the successive bed forms are excluded.

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Effects of ProBody Massage on Body Alignment and Plantar Pressure Balance in Middle-aged Men with Musculoskeletal Diseases

  • Oh, Se-Jin;Lee, Joong-Sook
    • 한국운동역학회지
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    • 제26권2호
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    • pp.213-220
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    • 2016
  • Objective: The purpose of this study was to investigate the effect of an 8-week ProBody massage program on body alignment and plantar pressure balance in middle-aged men with musculoskeletal diseases. Method: The subjects of this study were 20 middle-aged men with musculoskeletal diseases in B Metropolitan City who participated in an 8-week ProBody massage program conducted twice a week. Physical characteristics (height, weight, and body mass index), body alignment, and plantar pressure were assessed before and after the experiment. Results: The 20 middle-aged men with musculoskeletal diseases who underwent the ProBody massage program showed positive changes in physiological characteristics, body alignment, and plantar pressure balance. Conclusion: Consequently, the 8-week ProBody massage program was suggested to be effective for improving and preventing postural imbalance in middle-aged men with musculoskeletal diseases. The ProBody massage program could also be utilized to improve the body alignment and plantar pressure balance in middle-aged women with musculoskeletal diseases.

자세 균형 제어 시 동요의 강도와 관절 반발력의 상관관계 (Correlation between sway magnitude and joint reaction force during postural balance control)

  • 서민좌;조원학;최현기
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2004년도 추계학술대회 논문집
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    • pp.1160-1165
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    • 2004
  • The purpose of this study was to calculate three dimensional angular displacements, moments and joint reaction forces of the ankle joint during the waist pulling, and to assess the ankle joint reaction forces according to different perturbation modes and different levels of perturbation magnitude. Ankle joint model was assumed 3-D ball and socket joint which is capable of three rotational movements. We used 6 cameras, force plate and waist pulling system. Two different waist pulling systems were adopted for forward sway with three magnitudes each. From motion data and ground reaction forces, we could calculate 3-D angular displacements, moments and joint reaction forces during the recovery of postural balance control. From the experiment using falling mass perturbation, joint moments were larger than those from the experiment using air cylinder pulling system with milder perturbation. However, JRF were similar nevertheless the difference in joint moment. From this finding, we could conjecture that the human body employs different strategies to protect joints by decreasing joint reaction forces, like using the joint movement of flexion or extension or compensating joint reaction force with surrounding soft tissues. Therefore, biomechanical analysis of human ankle joint presented in this study is considered useful for understanding balance control and ankle injury mechanism.

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식이섭취와 작업할동량이 일부 농촌여성들의 리보플라빈 영양상태에 미치는 영향 (Effects of Dietary Intake and Work Activity on Seasonal Variation of Riboflavin Status in Rural Women)

  • 임화재
    • Journal of Nutrition and Health
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    • 제29권9호
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    • pp.1003-1012
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    • 1996
  • We examined the relationship among riboflavin intake, work activity, erythrocyte glutathione reductase activity coefficient(EGR AC)and urinary riboflavin excretion. We also attempted to determine factors affecting seasonal riboflavin status of rural women. All information about nutrient intake, work activity and riboflavin biochemical status was repeatly collected in three seasons ; farming season(June), harvest season(October), nonfarming season(February). EGR AC was negatively correlated with riboflavin intake(P<0.005) and positively correlated with the duration(min) of farming activity(P<0.005) and the percentage of lean body mass(LBM) (%) representing long term physical activity(P<0.05) in harvestseason. Urinary riboflavin excretion was positively correlated with the ratio of riboflavin intake to 1,000kcal of energy expenditure (P<0.05) in farming season and negatively correlated with the duration(min) of farming activity (P<0.05) and crude nitrogen balance(P<0.005) in harvest season. It appeared that EGR AC seems to increase and urinary riboflavin excretion seems to decrease as work activity increase. Therefore work activity would be expected to deteriorate riboflavin status. Multiple regression analysis of variables showed that in general EGR AC was affected by riboflavin and energy intakes, energy expenditure, energy balance, the duration(min) of farming activity, LBM (%). Urinary riboflavin excretion was affected by riboflavin and protein intakes, LBM(kg) and crude nitrogen balance. Crude nitrogen balance affected urinary riboflavin excretion in all seasons. The result indicated that work activity as well as nutrient intake seemed to affect riboflavin status, especially EGR AC was affected preferentially be work activity in all seasons.

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Available Electron Balance에 의한 발효과정의 에너지효율 (Efficiency Analysis of fermentation Process on Available Electron Balance)

  • Lee, Kyung-Hee;Kang, Woo-Kyu;Kim, Byung-Woo
    • 한국미생물·생명공학회지
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    • 제16권2호
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    • pp.85-91
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    • 1988
  • Ruminococcus albus와 Ruminococcus flavefaciens 두 균주를 사용하여 기질 cellulose로부터 균체량과 생성물 형성에 대해서 available electron balance를 적응한 에너지 효율이 검토되었다. 실험 결과로부터 진정수율(true growth yield) 값인 η$_{max}$, η$^{max}_{th}$ 두 값과 유지 계수값인 m$_{e}$ 값이 이론적 접근으로부터 얻어진 값들과 비교 검토되어졌다. 실험치는 $Y^{max}_{ATP}$=10.5g cells/mole ATP 값을 적용한 이론치와 비슷하므로 Ruminococcus albus, Ruminococcus flavefaciens의 $Y^{max}_{ATP}$ 값은 10.5와 비슷한 값을 갖는 것으로 사료되어진다.

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Balance Evaluation after Reconstruction of Medial Patellar Luxation in Small-Sized Dogs with Wii Balance Board

  • Lee, Shinho;Lee, Joo-Myoung;Park, Hyunjung;Cha, Yuri;Cheong, Jongtae
    • 한국임상수의학회지
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    • 제36권6호
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    • pp.301-305
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    • 2019
  • Wii® balance board (WBB, Nintendo, Japan) is a device that can measure and record the center of pressure path length (CPPL) and 95% confidence ellipse area (Area 95) in relation to body sway. For evaluating measure of improvement after reconstruction of medial patellar luxation (MPL) in small sized dogs, A total of 6 dogs with limping and lameness gait attributed to Grade II, III or IV MPL were evaluated. Dogs were measured for difference of extension and flexion range of motion in the stifle (dROM), muscle mass, lameness, willingness to bear weight on the affected limb while standing, and willingness to lift the contralateral limb scores, CPPL and Area 95 of WBB on pre-surgery, post-surgery 4, 8 weeks. CPPL was significantly different on pre-surgery compared with post-surgery 8 weeks (p < 0.05). Except for CPPL, measured variables were significantly different on pre-surgery compared with post-surgery 4 and post-surgery 8 weeks (p < 0.01).

포화된 다공질 매체의 질량 보존과 운동량 보존에 대한 Arbitrary Lagrangian Eulerian(ALE) 정식화 (Formulation of Mass Conservation and Linear Momentum Conservation for Saturated Porous Media in Arbitrary Lagrangian Eulerian(ALE) Description)

  • 박대효;정소찬;김원철
    • 한국지반환경공학회 논문집
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    • 제4권1호
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    • pp.5-10
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    • 2003
  • 다공질 매체 속의 내부 구조를 이루고 있는 고체 부분과 유체 부분은 서로 다른 재료특성을 가지는 물체들로 구성되어 있고 각 구성물들은 서로 다른 물리적 성질과 화학적 성질을 가지면서 서로 다른 상대 속도를 가지고 이동하기 때문에 포화된 다공질 매체의 구조적 변형 거동을 해석하는 것은 매우 복잡하다. 변형 거동에 영향을 주는 여러 가지 복합적인 요인들이 고려된 다공질 매체의 변형 거동을 해석하고 규명하기 위하여 Arbitrary Lagrangian Eulerian(ALE) 정식화가 이루어진 구성방정식을 세워야 할 필요가 있다. ALE 정식화는 Lagrangian 요소와 Eulerian 요소의 장점을 최대화 시키고 단점을 최소화 시키는 것에 주안점을 두기 때문에 고체 부분과 유체 부분을 함께 고려해야 하는 다공질 매체의 변형 거동을 해석하는데 있어서 적합한 방법이라고 할 수 있다. 그렇기 때문에 여기서는 포화된 다공질 매체의 보존 법칙들에 대한 ALE 정식화가 이루어진다. 고체 부분과 유체 부분의 질량 보존 법칙에 대하여 ALE 정식화가 이루어진 식이 각각 표현되고 다공질 매체 전체에 대한 운동량 보존 법칙이 표현된다.

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Liquid Chromatography-Mass/Mass Spectrometry (MS)와 Gas Chromatography-MS를 이용한 농축 액상 비료제품 중 Indole-3-acetic acid 및 Indole-3-butyric acid 정량분석능 비교 (Comparison of Liquid Chromatography-Mass/Mass Spectrometry (MS) and Gas Chromatography-MS for Quantitative Analysis of Indole-3-acetic acid and Indole-3-butyric acid from the Concentrated Liquid Fertilizer)

  • 김진효;박종민;최근형;박연기;임건재;김두호;권오경
    • Journal of Applied Biological Chemistry
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    • 제56권1호
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    • pp.53-57
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    • 2013
  • 비료제품에는 의도적 혹은 비의도적으로 농약으로 등록된 indole-3-acetic acid (IAA) 및 indole-3-butyric acid (IBA)성분에 대한 잔류 가능성이 꾸준히 제기되고 있으나, 생장조정제가 아닌 비료제품에서 mg/L 수준의 옥신류 잔류분석법이 마련되어 있지 않았다. 따라서, 본 연구에서는 생체시료에 미량 잔류하는 IAA 및 IBA 분석에 사용되어 온 liquid chromatography-mass/mass spectrometry (LC-MS/MS)와 gas chromatography-MS 기기분석법을 활용하여 농축 액상비료제품에 적용할 수 있는지 조사하였으며, 액상 비료제품에 적용 가능한 정밀기기 분석법을 개발하고자 하였다. 수용액 상태의 시료에서 식물 생장호르몬인 IAA와 IBA를 가장 손쉽게 정제할 수 있는 방법으로 hydrophile-lipophile balance (HLB) solid phase extraction를 활용하였으나, 제한된 조건에서 LC-MS/MS를 통한 정량분석은 적합한 회수율을 확보하지 못하였고, 정성분석만 가능함을 확인하였다. 반면, 비료제품 250배 희석액을 사용하여 HLB 정제, trimethylsilyl chloride을 이용한 methylation을 통한 GC-MS 분석에서는 검출한계 1.4 mg/L과 93-107%의 회수율로 액상 비료제품에서 IAA와 IBA 정량분석법을 확립할 수 있었다.