• 제목/요약/키워드: logarithmic scale

검색결과 92건 처리시간 0.024초

발병초기 Bell's Palsy 환자의 안면부 피부전기활동성 차이에 관한 연구 (Differences Between Facial Electrodermal Activities of Paralyzed Side and Those of Normal Side in Acute Stage of Bell's Palsy Patients)

  • 한경숙;남동현;고형균;박영배
    • 대한한의진단학회지
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    • 제9권2호
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    • pp.72-82
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    • 2005
  • Background and purpose: Bell‘s Palsy is a condition that causes the facial muscles to weaken or become paralyzed. It's caused by trauma to the 7th cranial nerve, and is not permanent. The aim of this study is to be convinced of differences between facial electrodermal activities of paralyzed side and those of normal side in acute stage of Bell's Palsy patients Methods: Electrodermal activity (EDA) was performed within 1 week after the onset of facial palsy and facial nerve electromyography (EMG) at 2 weeks after the onset. The recovery of facial nerve function was documented by House and Brackmann grading. All the patients were followed up weekly until recovery or up to 6 weeks. Results: There was significant differences (conductivity A: t=3.319, p=0.002; conductivity C: t=2.699, p=0.010) between facial electrodermal conductivities of paralyzed side and those of normal side in acute stage of Bell's Palsy patients (N=45). And the result showed that logarithmic scale of electrodermal conductivity A value ratio obviousely decreased with logarithmic scale of EMG zygomatic branch amplitude ratio (r=-0.472, p=0.143); logarithmic scale of capacitance B, logarithmic scale of EMG temporal branch amplitude ratio (r=-0.422, p=0.133); logarithmic scale of conductivity C, logarithmic scale of EMG buccal branch amplitude ratio (r=-0.545, p=0.083) (N=12). Conclusion: Electrodermal conductivities increased in paralyzed facial side in acute stage of Bell's Palsy patients.

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학교수학 관점에서 살펴본 로그의 역사적 배경과 교수-학습 방법에 대한 고찰 (The Analysis of the Way of Teaching and Learning Logarithms with a Historical Background in High School Mathematics)

  • 조정수
    • 한국수학교육학회지시리즈E:수학교육논문집
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    • 제25권3호
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    • pp.557-575
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    • 2011
  • 본 연구는 고등학교 수학에서 지도되고 있는 로그의 교수-학습 방법에 대한 새로운 관점과 방법을 고찰해보고 이를 통해 학교수학의 로그 지도에 대한 시사점을 제시하는데 목적이 있다. 이를 위하여 로그의 역사적 배경을 John Napier, 17세기 과학에 대한 로그의 영향, 그리고 로그계산자와 로그계산 방법을 중심으로 살펴보았다. 이런 배경과 함께 로그의 교수-학습 방법에 대한 고찰에서는 함수 개념을 이용한 로그의 도입, 상용로그를 이용한 로그계산, 밑의 변환 공식에 대해서 고찰하였다. 이런 역사적, 교수방법적 고찰을 통하여 학교수학에서 로그 지도에 대한 여섯 가지 시사점을 제시하였다.

먹는 물의 수질평가방법에 관한 연구 (A Study on Evaluation Method of Mineral Water Quality)

  • 옥삼복;정용준;정승원
    • 한국환경과학회지
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    • 제8권5호
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    • pp.601-605
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    • 1999
  • This study has been performed to evaluate mineral water quality by using four parameters [Mg]/[Ca], [Na]/[K], [Mg]+[Ca]/[Na]+[K] and total hardness(as CaCO3 mg/ℓ). The four parameters has been ploted in a general scale and logarithmic scale, respectively. The method of general scale is not applicable for evaluation on several parameters. Therefore, the logarithmic scale is applied instead to settle the problem. The evaluation of the water quality is based on standard sample S, and the results of the 6 domestics and 5 overseas sample evaluation are as follow. At present, evaluation of the water quality on the mineral water can be done by using four parameters calculated from only cation concentration printed on the bottle's marking.

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대수계수율계에 관한 연구 (A Study on the Logarithmic Counting Ratemeter)

  • 이병선;정호균
    • 대한전자공학회논문지
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    • 제12권1호
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    • pp.12-17
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    • 1975
  • 광대역의 계수율을 선택 스윗치 없이 계측하기 위한 대수계수율회로에 관한 해석을 하였고 그에 의한 다데케이드 계수율회로의 구성방법과 실험결과를 지시하였다. 이 대수계수율회로는 주기적인 입력 펄스 뿐만 아니라, Poisson분포를 갖는 random한 펄스에 대하여도 대수적인 응답특성을 가지며 계수율 1pps로 부터 $10^5$pps까지 데케이드의 영역에 걸쳐 좋은 대수특성을 가지며 또한 낮은 영역과 높은 영역에서의 특성저하의 원인을 규명하여 양단에서의 특성을 효과적으로 보상하였다.

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Effect of growth phase of cyanobacterium on release of intracellular geosmin from cells during microfiltration process

  • Matsushita, Taku;Nakamura, Keisuke;Matsui, Yoshihiko;Shirasaki, Nobutaka
    • Membrane and Water Treatment
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    • 제6권3호
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    • pp.225-235
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    • 2015
  • During low-pressure membrane treatments of cyanobacterial cells, including microfiltration (MF) and ultrafiltration (UF), there have reportedly been releases of intracellular compounds including cyanotoxins and compounds with an earthy-musty odor into the water, probably owing to cyanobacterial cell breakage retained on the membrane. However, to our knowledge, no information was reported regarding the effect of growth phase of cyanobacterial cells on the release of the intracellular compounds. In the present study, we used a geosmin-producing cyanobacterium, Anabaena smithii, to investigate the effect of the growth phase of the cyanobacterium on the release of intracellular geosmin during laboratory-scale MF experiments with the cells in either the logarithmic growth or stationary phase. Separate detection of damaged and intact cells revealed that the extent of cell breakage on the MF membrane was almost the same for logarithmic growth and stationary phase cells. However, whereas the geosmin concentration in the MF permeate increased after 3 h of filtration with cells in the logarithmic growth phase, it did not increase during filtration with cells in the stationary phase: the trend in the geosmin concentration in the MF permeate with time was much different between the logarithmic growth and stationary phases. Adsorption of geosmin to algogenic organic matter (AOM) retained on the MF membrane and/or pore blocking with the AOM were greater when the cells were in the stationary phase versus the logarithmic growth phase, the result being a decrease in the apparent release of intracellular geosmin from the stationary phase cells. In actual drinking water treatment plants employing membrane processes, more attention should be paid to the cyanobacterial cells in logarithmic growth phase than in stationary phase from a viewpoint of preventing the leakage of intracellular earthy-musty odor compounds to finished water.

문서 패턴 영상 분별에 관한 연구 (A Study on the Classification of Document Pattern Image)

  • 진용옥;허동근
    • 대한전자공학회논문지
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    • 제26권10호
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    • pp.1554-1560
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    • 1989
  • This paper suggests the algorihtm which extracts the classification parameter relative to the only feature of document patterns even though they are rotated or scaled, and also classifies them. With the complex logarithmic conformal mapping, the sample of the document pattern image makes the pattern image of the complex logarithmic plane. Because the power spectrum of this plane is invariant to the rotation, and scale of the pattern image, it is used as the characteristics parameter of the patten image. By using the coherence function, this method analyzes the standard and input power spectrum. additionally, it classifies the input pattern image. Even though input image is rotated, our algorithm can classify it without reference to the rotation, and this is possible when the scale is in the range of 0.5-1.5.

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카본블랙에 의한 천연고무 물성치와 피로수명 변화에 대한 실험적 연구 (An Experimental Study on the Change of the Material Properties and the Fatigue Life of Natural Rubber due to Carbon Black)

  • 김재훈;김영학;정현용
    • 대한기계학회논문집A
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    • 제25권11호
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    • pp.1887-1894
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    • 2001
  • The effects of carbon black on the material properties and the fatigue life of the carbon-black filled natural rubbers were investigated. Different kinds of carbon blacks resulted in different fatigue lives, hysteresis, and critical J-values. It was noticed that the hysteresis was inversely proportional to the difference between DBPA and CTAB, and the critical J-value was almost the same regardless of the length of a precrack. In addition, different kinds of carbon blacks resulted in different fracture morphologies, and micro-scale and macro-scale roughnesses. The critical J-value was proportional to the micro-scale roughness. and it seemed relate to the size distribution of carbon black particles. By reviewing all the experimental data. it was finally noticed that the logarithmic value of the fatigue life could be linearly expressed by a multiplication of the critical J-value and the logarithmic value of the hysteresis.

Memory-Efficient Hypercube Key Establishment Scheme for Micro-Sensor Networks

  • Lhee, Kyung-Suk
    • ETRI Journal
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    • 제30권3호
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    • pp.483-485
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    • 2008
  • A micro-sensor network is comprised of a large number of small sensors with limited memory capacity. Current key-establishment schemes for symmetric encryption require too much memory for micro-sensor networks on a large scale. In this paper, we propose a memory-efficient hypercube key establishment scheme that only requires logarithmic memory overhead.

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Numerical Calculation of the Relaxation Spectrum from the Correlation Function$^\dag$

  • Lee, Hoo-Sung
    • Bulletin of the Korean Chemical Society
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    • 제8권5호
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    • pp.406-408
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    • 1987
  • It has been shown that the distribution of relaxation times, H(ln $\tau$), in semi-logarithmic time scale can easily be calculated numerically from the derivative of the relaxation function in semilogarithmic scale. In that, ln$\tau$, the abscissa, is divided into N different segments of equal size, then H is considered to be a linear function of ln $\tau$within each segment. The technique has been applied to a Williams-Watts function as well as to the relaxation function obtained by photon correlation spectroscopy from atactic polystyrene glass. It has been demonstrated that the relaxation functions can be precisely reproduced from the calculated distribution functions.

Al-7wt%Si-0.3wt%Mg 합금의 응고 및 미세조직에 미치는 Sr 첨가와 금형예열온도의 영향 (The Effect of Sr Addition and Mold Preheating Temperature on the Solidification and Microstructure of Al-7wt%Si-0.3wt%Mg Alloy)

  • 권일수;김경민;윤의박
    • 한국주조공학회지
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    • 제17권6호
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    • pp.608-614
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    • 1997
  • The effect of mold preheating temperature on the microstructure such as grain size, eutectic silicon morphology was investigated for the Al-7wt%Si-0.3wt%Mg alloy. Microstructural variations have been characterized as a function of Sr addition and cooling rate during solidification. Microstructures were correlated with cooling rate, local solidification time and eutectic nucleation temperature, etc. In this study, Sr addition caused increase of local solidification time, undercooling and reduction of eutectic plateau temperature. In logarithmic scale, local solidification time was in inverse proportion to cooling rate. Eutectic nucleation temperature was in inverse proportion to cooling rate of logarithmic scale. Increasing the cooling rate refined dendrite arm spacing and eutectic silicon. Dendrite arm spacing was logarithmically in inverse proportion to cooling rate. Without modifier addition, eutectic silicon was modified at cooling rate of $7^{\circ}C/s$ or higher.

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