• 제목/요약/키워드: within part variation

검색결과 134건 처리시간 0.038초

압력 및 용존산소 농도가 활성슬러지에 미치는 영향 (Effects of Pressure and Dissolved Oxygen Concentration on the Activated Sludge)

  • 양병수;신현무
    • 한국환경과학회지
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    • 제4권3호
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    • pp.259-267
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    • 1995
  • This study was conducted to evaluate the effects of pressure and dissolved oxygen concentration on the activated slut비e and to determine the optimum depth of deep shaft process. Some results from this study were summarized as follows. 1. It is considered that low sludge product in the activated sludge system maintaining high dissolved oxygen concentration is attributed to the increase of endogeneous respiration rate caused by the increase of aerobic zone in the sludge floe. 2. The increase of dissolved oxygen concentration does not affect to the increase of organic removal efficiency greatly and therefore the limiting factor is the substrate transfer into the inner part of floe. 3. The yield coefficient, Y is decreased in proportion to the increase of oxygen concentration. In this study, Y values arre ranged from 0.70 to 0.41 according to the variation of dissolved oxygen concentration from 18.0mg/$\ell$ to 258 mg/$\ell$. 4. The optimum depth of deep shaft process should be determined within the limits of non-toxicity to the microorganism and it is about loom in this study.

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동기형 직선유도전동기의 동작특성 (Performance Characteristics of Tubular Linear Iduction Motor)

  • Lee, Eun-Ung
    • 대한전기학회논문지
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    • 제36권3호
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    • pp.153-162
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    • 1987
  • The purpose of this paper is to analysis and develop theoretically the characteristics of tubular linear induction motor, which is a special industrial motor that generates directly thrust force from electrical power. The Poisson equation about vector potential which is created by the application of Maxwell electromagnetic equation with the speed considered, results in modified Bessel equation by the assumption that is applied to each region of the experimental motor. Vector potential, magnetic flux density, secondary current, and thrust force according to its region respectively were found out by substituting boundary condition for this equation and rearranging. Besides, a attendant materials, that is, thermal characteristic, which is one of the characteristics under the operation of experimental motor each part's magnetic flux distribution characteristics within active zone, the required time for reciprocating motion, and variation of power factor vs. a slip were found.

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마이크로 Inchworm motor 용 Hinge 구조의 특성 해석 (Analysis of hinge structures for micro inchworm motor)

  • 김원효;권호남;김영윤;윤성식;이종현
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 추계학술대회 논문집
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    • pp.1088-1091
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    • 1997
  • This paper describes the characteristic of hinges on which a lever pivots within a limited angle due to the torque. The hinges are exerted by the thermally expanded actuators connected with a level through hinges. To enhance the stroke of inchworm actuator, FEM(Finite Element Method) was utilized for the characterization in view of stress displacement according to the variation of notch radius and notch width. As a result, notch width of the hinges plays an important part in improvement of micro inchworm actuator.

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Rate-sensitive analysis of framed structures Part I: model formulation and verification

  • Izzuddin, B.A.;Fang, Q.
    • Structural Engineering and Mechanics
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    • 제5권3호
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    • pp.221-237
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    • 1997
  • This paper presents a new uniaxial material model for rate-sensitive analysis addressing both the transient and steady-state responses. The new model adopts visco-plastic theory for the rate-sensitive response, and employs a three-parameter representation of the overstress as a function of the strain-rate. The third parameter is introduced in the new model to control its transient response characteristics, and to provide flexibility in fitting test data on the variation of overstress with strain-rate. Since the governing visco-plastic differential equation cannot be integrated analytically due to its inherent nonlinearity, a new single-step numerical integration procedure is proposed, which leads to high levels of accuracy almost independent of the size of the integration time-step. The new model is implemented within the nonlinear analysis program ADAPTIC, which is used to provide several verification examples and comparison with other experimental and numerical results. The companion paper extends the three-parameter model to trilinear static stress-strain relationships for steel and concrete, and presents application examples of the proposed models.

위 배출시간 측정의 분석방범에 대한 연구 (Analysis in Measurements of Gastric Emptying Time)

  • 이춘호;이만구
    • 대한방사선기술학회지:방사선기술과학
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    • 제20권1호
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    • pp.35-38
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    • 1997
  • Scintigraphic measurement of gastric emptying time has been reported to be influenced by the variation in depth of radionuclide within the stomach. This study was designed to clarify whether a part of the variability in gastric emptying could be ascribed to a relationship between anterior image, the total anteroposterior Image and the tissue attenuation correction(geometric mean). A dual-head scintillation camera(ADAC, USA) was used to investigate effect of such changes. We were performed 16 normal subject gastric emptying studies with $^{99m}TC$ labelled scramble egg, milk and solid meal(610 Kcal, 300 g) The results are as follows; On anterior Image, $T_{1/2}$ emptying time was delayed by 5 min, 6.5%(range $3{\sim}18\;min,\;5{\sim}31.4%$) compared with the geometric mean. But there was no different gastric emptying time between the total anteroposterior image and geometric mean. Therefore, if will be useful to use the method of geometric mean or the total anteroposterior image to evaluate the gastric emptying time accurately.

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REE variation of Ultramafic rocks related to the Serpentinization, the Gyeonggi Massifs in the western Korea

  • Seo, Ji-Eun;Park, Seon-Gyu;Oh, Chang-Whan;Song, Suck-Hwan
    • 대한자원환경지질학회:학술대회논문집
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    • 대한자원환경지질학회 2003년도 춘계 학술발표회 논문집
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    • pp.194-195
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    • 2003
  • High-pressure amphibolite-facies rocks with serpentinized ultramafic rocks occur in the Gyeonggi Massif. Ultramafic rocks occur as lenses within Precambrian granite gneiss, which showing dominantly tectonic lines of NNE directions as well as east extensional area of the chinese collision belt between south and north China block(\ulcorner). This study regionally makes a comparative study of ultramafic rocks in the western part of the Gyeonggi Massif in Korea. (omitted)

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The Thermal-Hydraulic Effects of Thimble Plug Removal for Westinghouse type PWR Plants

  • B. S. Jun;Park, E. J.;Kim, K. H.;Park, B. S.;K. L. Jeon
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(2)
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    • pp.166-172
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    • 1996
  • The thermal-hydraulic effects of removing the RCC guide thimble plugs are evaluated for Westinghouse type PWR plants as a part of feasibility study: core outlet loss coefficient, thimble bypass flow, and best estimate flow. It is resulted that the best estimate thimble bypass flow increases about by 2% and the best estimate flow increase approximately by 1.2%. The resulting DNBR penalties can be covered within the current DNBR margin. Accident analyses are also investigated and the dropped rod transient is shown to be limiting and relatively sensitive to bypass flow variation.

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한국 남부의 쌍화산대 가능성: 지화학적 근거 (A Possibility of Dual Volcanic Chains in the Southern Part of Korea: Evidences from Geochemistry)

  • Jong Gyu;Jin Seop;Maeng Eon;Kyonghee
    • 자원환경지질
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    • 제33권4호
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    • pp.249-260
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    • 2000
  • 한국 남부에서 섭입 해구의 방향과 나란히 쌍으로 발달한 화산대가 발견된다. 경상분지와 영동-광주 함몰대의 화산암류는 거의 나란한 양상을 보이며, 이들은 각각 동일한 섭입 체계에 따르는 첫 번째 화산대, 두 번째 화산대이다. 경상분지와 영동-광주 함몰대 화산암류의 불호정성 원소 함량은 호를 가로지르는 변화를 뚜렷하게 보인다. 즉, 첫 번째 화산대 (경상분지 및 남해안 도서지역)용암들의 불호정성 원소 함량은 두 번째 화산대 (영동-광주 함몰대)에 비해 더욱 결핍되며 두 번째 화산대에서 더욱 증가하는 경향을 보인다. 이와 같이 호를 가로지르는 변화를 보이는 것은, 탈수과정 동안 유체상과 공존하는 고체상의 차이에 기인한 것으로 보인다. 두 번째 화산대의 불호정성 원소의 함량, Zr/Y 비, Rb/K 비는 첫 번째 화산대에 비해 더 깊은 깊이에서 더 적은 정도의 부분 용융, 그리고 용융 과정에서의 잔류 석류석에 기인할 것이다.

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옥수수에 있어서 Peroxidase 8의 변이 (Variation of Peroxidase 8 in Maize, Zea mays, L.)

  • 최봉호
    • 한국작물학회지
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    • 제28권3호
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    • pp.374-378
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    • 1983
  • 옥수수에 있어서 다형현상에 관한 연구의 일환으로 Peroxidase 8에 대하여 수평전기 영동법에 의한 변이를 본 결과 중심주의 Peroxidase 8은 옥수수의 계통이나 품종에 따라 Fast, Slow, Fast/slow 밴드를 보여 주어 Peroxidase 8은 단일유전인자에 의하여 좌우된다고 생각되며 특히 본 연구에서 동일한 자식계통에 있어서도 상이한 밴드의 패턴을 보여주었는데 이는 사용한 계통이 동질접합체가 되지 못하였거나 혼종된 것이 아닌가 생각되어진다. 그러나 대가 자식계통의 옥수수는 Fast나 Slow의 단일 밴드패턴을 보여주었는데 반하여 단교잡 내지는 합성품종은 여러 가지 형태의 패턴을 보여주었다. 그리고 Peroxidase 8은 대개 초엽(중심주)이나 목화되지 않은 조직에서 흔히 관찰되나 Peroxidase 3와도 관계를 가지고 있는 것으로 생각되어진다. 특히 옥수수 줄기의 절에서 관찰되는 Peroxidase 3과 8의 패턴으로 보아 이 두 효소는 서로 상반되는 작용을 한다고 생각한다.

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겨드랑둘레선의 최적 프레임 생성에 관한 연구 (A Study on the Optimal Frame Design of Armscye Circumference)

  • 박선미;최경미;남윤자;류영실;전정일
    • 한국의류산업학회지
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    • 제11권5호
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    • pp.788-798
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    • 2009
  • This study aims to develop a highly reproducible, optimal frame design algorithm using variations in the curvature of armscye circumference, which will provide the basics for remodeling the 3D human body shape with the concept of reverse design used to develop total contents for the apparel industry. 1. The results of the experiment proved that ratio value was significantly efficient than absolute value of curvature variation to extract feature points in the armscye circumference 2. For the shoulder(1st and 2nd quadrant) and front armhole(3rd quadrant) parts of the armscye circumference, frame remodeling with the positive point of inflection led to the completion of a highly reproducible frame. 3. Similarly, even for the rear armhole part(4th quadrant) in the armscye circumference, it was found that frame remodeling using the positive maximum point of inflection resulted in highly reproducible body shape with the maximum point of inflection situated within the range of split angles $305^{\circ}{\sim}330^{\circ}$, while frame remodeling using simultaneously the two largest points of inflection including maximum point of inflection led to highly reproducible body shape with the maximum point of inflection out of the range $305^{\circ}{\sim}330^{\circ}$. 4. Based upon the optimal frame design algorithm developed in this study, section-specific feature points in the armscye circumference were extracted depending on the rate of curvature variation and remodeling with spline curves was conducted. The results indicate a remarkably high reproducibility(98.6%) and suggest that the algorithm developed in this study is suitable for human body modeling.