• 제목/요약/키워드: Attraction rate

검색결과 72건 처리시간 0.027초

트랩식물로서 해바라기의 미국선녀벌레 유인효과 (Attraction Effect of Sunflowers to Metcalfa pruinosa (Say) (Hemiptera: Flatidae) as Trap Plants)

  • 최용석;황인수;이경주;김민중;백성훈;서화영
    • 한국응용곤충학회지
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    • 제59권4호
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    • pp.427-432
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    • 2020
  • 해바라기, 콩, 들깨, 참깨를 트랩식물로 이용하여 미국선녀벌레 약충에 대한 유인효과를 조사한 결과, 실내실험의 경우, 어린단계와 성숙단계 모두에서 해바라기가 각각 평균 47.6%와 66.5%로 가장 높은 유인력을 보였고, 야외실험의 경우에도 어린단계와 성숙단계 모두에서 해바라기가 각각 평균 52.3%, 53.2%로 가장 높았다. 실내실험과 야외실험에서 어린단계의 콩은 시간이 지나면서 해바라기 다음으로 유인력이 높았으나 성숙단계의 콩은 들깨 보다도 낮은 유인력을 보였으며 실내실험과 야외실험간 비교에서 동일 트랩식물간 유의성은 없는 것으로 보아 미국선녀벌레 약충에 대하여 가장 유인력이 높은 식물은 해바라기였다.

Simulation for the effect of vertical groundwater flux on the subsurface temperature distribution

  • 신지연;이강근
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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    • pp.383-386
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    • 2006
  • Subsurface temperature is affected by heat advection due to groundwater advection. Temperature-depth profile can be perturbed especially when there are significant vertical groundwater flux caused by external force such as injection or extraction. This research is to clarify the change of subsurface temperature distribution when the 40m x l0m sandy aquifer is stimulated by two different vertical flux($case1:\;{\pm}10^{-5}m^3/s,\;case2:\;{\pm}4{\times}10^{-5}m^3/s$) using a program called HydroGeoSphere. The resulting temperature distribution contour map shows pumping causes vertical attraction of water from deeper and warmer place which result in rising up isotherm. Additionally more injection/extraction rate, more vertical groundwater flux leads to faster Increase in temperature near the pumping well.

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전기자극이 상처치유에 미치는 효과 (Effects of Electrical Stimulation on Wound Healing : Review of the Literature)

  • 김식현;김수민;김용수
    • 대한물리치료과학회지
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    • 제1권2호
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    • pp.333-343
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    • 1994
  • This study was performed to assess the efficacy of electrical stimulation for healing of wound in injured tissue, and to provide a baseline for electrical stimulation in the treatment. Although the specific mechanism by electrical stimulation which may promote injured tissue to heal is not known, generally many hypothesis exist such as bactericidal effect, enhanced circulation, stimulation of cellular biosynthesis and replication, and attraction of connective tissues and inflammatory cells The results of this study are as follows : 1. The healing of skin wound was facilitated by electrical stimulation 2. The capacity of collagen synthesis was significantly accelerated by electrical stimulation 3. The application of electrical stimulation to injured tissue may be helpful in augmenting the rate of wound contracture

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능동 진동제어용 전자기 액츄에이터 설계 (A Design of Electromagnet Actuator for Active Vibration Control)

  • 이주훈;전정우;황돈하;강동식;최영규
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.522-524
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    • 2005
  • In this paper, we address an actuator system, which suppresses the micro-vibration engaged by environment. The actuator system consists of two modules with a permanent and an electromagnet. In vertical mode, one module is upper the other is lower. For optimal control of alternating vibration, the rate of the attraction force and the repulsion force is exactly one. Generally, the repulsive force is smaller than the attractive force. For linear control of engaged vibration, the ratio of repulsive force and attractive force is designed to equal. The actuator system will be applied to an active vibration control system for precise vibration suppression. In this paper, the actuator structure and its important sizes are calculated by RMS and FEM analysis.

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Determinants of Foreign Direct Investment: Evidence from Vietnam

  • NGO, Minh Ngoc;CAO, Huy Hoang;NGUYEN, Long Ngoc;NGUYEN, Thuc Ngoc
    • The Journal of Asian Finance, Economics and Business
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    • 제7권6호
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    • pp.173-183
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    • 2020
  • The paper investigates the determinants of foreign direct investment (FDI) in Vietnam in 2000-2019 period. This study uses difference Generalized Methods of Moments (GMM) and Pooled Mean Group (PMG) to analyse panel data officially provided by General Statistical Office of Vietnam. The results show that market size impacts positively significant on FDI attraction: 1% -1.45% (PMG) and 1% -1.25% (GMM). Besides, some other factors have positive influences as labor force, macroeconomic policy, macroeconomic stability and skilled labor. Meantime, the trade openness negatively affects FDI inflows in the short-term, while not being statistically significant in the long-term. Moreover, economic shocks often have a negative impact on FDI inflows. The findings of this study lead to the following recommendations. First, authorities should pay special attention to encourage economic growth rate in Vietnam to expand market size because this is the first priority of foreign investors. Second, authorities need to continue increasing the rate of skilled labor, especially highly qualified management force, engineers and well-skilled workers. Third, the authorities should adjust trade openness to boost the role of its determinant in attracting FDI inflows. Fourth, macroeconomic stability needs to be governed by international standards in order to secure the belief of foreign investors in the long-term.

Experimental Study on the Enhancement of Particle Removal Efficiency in Spray Tower Scrubber Using Electrospray

  • Kim, Hyeok-Gyu;Kim, Hong-Jik;Lee, Myong-Hwa;Kim, Jong-Ho
    • Asian Journal of Atmospheric Environment
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    • 제8권2호
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    • pp.89-95
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    • 2014
  • There have been a lot of efforts to keep permissible emission standards and to reduce the amount of emitted air pollutants. There are several air pollution control equipments, however, wet scrubber is used to remove particulate matters and gaseous pollutants simultaneously, even if it has low collection efficiency in the particle size less than $5.0{\mu}m$. To overcome this problem, we introduced a spray tower scrubber with an electrospray system which a high voltage was indirectly applied. We found that collection efficiency of fine particles in the electrospray system was improved by increasing electrical field strength and the ratio of liquid-gas flow rate (from 41% to 84% for $0.3{\mu}m$ particles). In addition, a number of small droplets generated from an electrospray system led high collection efficiency, resulting from electrostatic attraction between droplets and particles and higher collision frequency. Therefore, we can conclude that the introduction of an electrospray system is quite effective to increase the particle removal efficiency of a spray tower scrubber.

비틀림 비선형성을 갖는 2차원 익형의 Critical Slowing Down 을 이용한 Limit Cycle Flutter 예측 인자 (Warning Signal for Limit Cycle Flutter of 2D Airfoil with Pitch Nonlinearity by Critical Slowing Down)

  • 임주섭;이상욱;김태욱
    • 한국항공운항학회지
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    • 제21권4호
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    • pp.47-52
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    • 2013
  • In this paper, limit cycle flutter induced by Hopf bifurcation is studied with nonlinear system analysis approach and observed for the critical slowing down phenomenon. Considering an attractor of the dynamics of a system, when a small perturbation is applied to the system, the dynamics converge toward the attractor at some rate. The critical slowing down means that this recovery rate approaches zero as a parameter of the system varies and the size of the basin of attraction shrinks to nil. Consequently, in the pre-bifurcation regime, the recovery rates decrease as the system approaches the bifurcation. This phenomenon is one of the features used to forecast bifurcation before they actually occur. Therefore, studying the critical slowing down for limit cycle flutter behavior would have potential applicability for forecasting those types of flutter. Herein, modeling and nonlinear system analysis of the 2D airfoil with torsional nonlinearity have been discussed, followed by observation of the critical slowing down phenomenon.

Phototactic behavior 9: phototactic behavioral response of Tribolium castaneum (Herbst) to light-emitting diodes of seven different wavelengths

  • Song, Jaeun;Jeong, Eun-Young;Lee, Hoi-Seon
    • Journal of Applied Biological Chemistry
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    • 제59권2호
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    • pp.99-102
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    • 2016
  • The phototactic behavioral responses of Tribolium castaneum adults to light-emitting diodes (LEDs) of seven different wavelengths were determined under various conditions (light exposure times, light sources, and luminance intensities) and compared with those of a black light bulb (BLB) under laboratory conditions. Based on the attractive rate (%) of T. castaneum adults under optimal conditions (50 lx and an 48 h exposure time) in the dark, red LED ($625{\pm}10nm$) exhibited the highest potential attractive rate (97.8 %), followed by yellow ($590{\pm}5nm$, 68.9 %), green ($520{\pm}5nm$, 55.6 %), infrared (IR) (730 nm, 54.4 %), white (450-620 nm, 41.1 %), blue ($470{\pm}10nm$, 34.4 %), and ultraviolet (UV) (365 nm, 0.06 %) LEDs. In comparison, red LED (97.8 %) was approximately 3.4 times more attractive to T. castaneum adults than the BLB (28.9 %). These results indicate that a red LED trap could be useful to control T. castaneum adults.

2단 정전식 세정집진기의 집진 및 가스제거 특성 (An Experiment on Particle Collection and Gas Removal in a 2-Stage Electrostatic Wet Scrubber)

  • 여국현;유경훈;손승우;김윤신
    • 설비공학논문집
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    • 제18권9호
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    • pp.745-752
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    • 2006
  • DOS and NaCl aerosol particles were used to determine collection efficiencies of a 2-stage electrostatic wet scrubber with respect to particle size. The DOS and NaCl aerosols have geometric mean diameters of 0.1-3.0 urn, geometric standard deviations of $1.1{\sim}1.8$ and total number concentrations of $450{\sim}2,400\;particles/cm^3$. The tested operating variables for the electrostatic wet scrubber included air velocity and water injection rate. It was shown from the experimental results that particle collection efficiencies increased in the submicron particle size range when different polarities were applied on the water nozzle and corona wire, respectively. This increase in the collection efficiency is attributed to strong electrostatic attraction between the negative water droplets and positive submicron particles. The collection efficiencies also increased when water injection rate was increased or air velocity was decreased. Meanwhile, the pressure drop across the wet scrubber decreased by 90% compared with the existing mechanical wet scrubber. Finally, ammonia gas was used to determine gas removal efficiencies. It was observed that the gas removal efficiencies increased when the air velocity was decreased or the water injection rate was increased.

전기활성 Poly(2-acrylamido-2-methylpropanesulfonic acid) 고분자 겔 구동기의 합성 및 특성분석 (Synthesis and Characterization of Electro-Active Poly(2-acrylamido-2-methylpropanesulfonic acid) Polymer Gel Actuator)

  • 송영진;심우선;김홍경;김학길;최혁렬;김훈모;전재욱;이영관;남재도
    • 폴리머
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    • 제25권5호
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    • pp.736-743
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    • 2001
  • N,N-Methylenebisacrylamide (MBAA)로 가교 결합된 electro-active 고분자(EAP) (poly(2-acrylamido-2-methylpropane sulfonic acid), PAMPS) 겔을 수용액 상에서 potassium persulfate를 개시제로 하여 라디칼 중합시켜 제조하였다. PAMPS 겔의 구동성을 부여하기 위하여 계면활성제로 팽윤하며 치환하였다. 계면활성제가 치환된 PAMPS 겔은 용액내의 인가된 전압하에서, 그 전기장 변화에 의해 큰 변위를 나타내는 구동특성을 보였다. PAMPS 겔은 빠른 응답속도와 가역적인 bending을 나타내었다. 겔의 구동원리는 양극과 PAMPS 겔 음이온간의 정전기 인력, 겔의 swelling-deswelling 효과 그리고 계면활성제의 소수성 반응의 협동적 과정으로 나타난다. PAMPS 겔의 응답속도는 인가된 전압 및 가교도가 증가할수록 증가하였으며, 구동이 반복적으로 진행됨에 따라 응답속도는 증가하였다. 겔의 두께가 증가하면 응답속도는 감소하였다.

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