• Journal of the Korean Data and Information Science Society
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• 제25권3호
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• pp.493-499
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• 2014

야구의 승률은 총득점의 제곱을 총득점의 제곱과 총실점의 제곱의 합으로 나눈 것으로 추정된다는 야구의 피타고라스 정리에 대하여 많은 연구들이 활발하게 진행되고 있다. 본 연구에서는 피타고라스 정리에 사용되는 지수에 대한 새로운 추정방법을 제안하며 평균제곱오차의 제곱근 (root mean squared error; RMSE)을 이용하여 널리 알려진 추정방법들과 상대적 효율성을 비교하였다. 사용된 데이터는 1982년부터 2013년 사이의 모든 한국프로야구 기록이며, 그 결과 제안된 방법은 기존의 방법보다 RMSE 관점에서 바람직하다고 간주된다.

• 생약학회지
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• 제50권1호
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• pp.46-52
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• 2019

This study was conducted to investigate the cholesterol and Triglyceride (TG) lowering and anti-obesity effects of water extract of vegetable formula (onion 25%, carrot 20%, Cabbage 20%, Sweet Pumpkins 20%, Chinese plum 5%, turmeric 5%, morus leaves 5%, SLS) in mice fed high fat-diet. ICR mice were divided into 3 groups; a normal diet group (ND), a high-fat diet group (HFD), a high-fat diet and SLS with 300 mg/kg treated group (HFD+SLS). Body fat gain was increased by high-fat diet and HFD+SLS group showed a definite weight loss. The total cholesterol level in the HFD+SLS group was 328.4 mg/dl which was 27.4% lower than that in the HFD group and the cholesterol-lowering effect of SLS was confirmed. The HFD + SLS group showed 118.1 mg/dl and the triglyceride level in the serum was decreased by 88.7% compared to the HFD group and SLS significantly decreased blood triglyceride levels. RT-PCR showed that the expression of PPAR-${\gamma}$ and the target gene SCD-1 was inhibited in a dose-dependent manner in the SLS-treated group. These results suggest that the SLS water extract may have a cholesterol and triglyceride-lowering effect and inhibit the expression of PPAR-${\gamma}$ and SCD-1 to have an anti-obesity effect.

• 정보보호학회논문지
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• 제19권4호
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• pp.63-75
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• 2009

해킹에 의한 개인정보의 유출 또는 기업의 관리 소홀로 인한 개인정보 유 노출 등의 침해사고가 다양한 형태로 발생하고 있으며, 이로 인한 피해범위도 확대되고 있다. 개인정보 유 노출 사고의 발생시 기업의 손실비용을 산출하는 일은 정보보호 투자에 대한 의사결정을 위해 필요하다. 본고는 개인정보 유 노출 사고로 인한 기업의 직접적이고 정량적인 손실비용 산출방안을 제시하고자 한다. 먼저 개인정보 침해사고에 의해 발생할 수 있는 손실비용을 범주에 따라 분류하고, 비용을 구성하는 요소들을 구체적으로 분석하였다. 또한 제시된 모형으로 2005${\sim}$2007년 동안 국내에서 발생한 개인정보 유 노출 사고의 손실을 추정하였고, 이를 일본의 사례와 비교 분석하여 시사점을 도출하였다.

• Journal of Biosystems Engineering
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• 제33권1호
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• pp.1-6
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• 2008

The output of the Stirling engine is influenced by the regenerator effectiveness. The regenerator effectiveness is influenced by heat transfer and flow friction loss of the regenerator matrix. In this paper, in order to provide basic data for the design of regenerator matrix, characteristics of flow friction loss were investigated by a packed method of matrix in the oscillating flow as the same condition of operation in a Stirling engine. As matrices, two different wire screens were used. The results are summarized as follows; 1. With the wire screen of No. 50 as regenerator matrices, pressure drop of working fluid of the oscillating flow is shown as 3 times higher than that of one directional flow, not too much influenced by the number of packed meshes. 2. With the wire screen of No. 100 as regenerator matrices, pressure drop of working fluid of the oscillating flow is shown as 2.5 times on the average higher than that of one directional flow, not too much influenced by the number of packed meshes. 3. Under one directional flow which used regenerator matrices with both 200, 240, and 280 wire screens of No. 50 and 320, 370, and 420 wire screens of No. 100, the relationship between the friction factor and Reynold No. is shown as the following formula. $$f=\frac{0.00326639}{Re\iota}-1.29106{\times}10^{-4}$$ 4. Under oscillating flow which used regenerator matrices with both 200, 240, and 280 wire screens of No. 50 and 320, 370, and 420 wire screens of No. 100, the relationship between the friction factor and Reynold No. is shown as the following formula. $$f_r=\frac{0.000918567}{Re\iota}+1.86101{\times}10^{-5}$$ 5. The pressure drop is shown as high in proportion as the number of meshes has been higher, and the number of packed wire screens as matrices increases.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 춘계학술대회논문집
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• pp.656-661
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• 2005

An optimization formulation of unconstrained damping treatment on beams is proposed to minimize vibration responses using a numerical search method. The fractional derivative model is combined with RUK's equivalent stiffness approach in order to represent nonlinearity of complex modulus of damping materials with frequency and temperature. The loss factors of partially covered unconstrained beam are calculated by the modal strain energy method. Vibration responses are calculated by using the modal superposition method, and of which design sensitivity formula with respect to damping layout is derived analytically. Plugging the sensitivity formula into optimization software, we can determine optimally damping treatment region that gives minimum forced response under a given boundary condition. A numerical example shows that the proposed method is very effective in minimizing vibration responses with unconstrained damping layer treatment.

• 조명전기설비학회논문지
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• 제29권9호
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• pp.65-70
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• 2015

Minimal line length enables low-cost construction of the transmission lines and low-loss transportation of electric power. This paper presents a derivation to determine the coordinate and length of the straight line that minimally connects two perpendicular lines x-axis and y-axis via a specific point, using the optimization technique. The author shows a formula to obtain the minimal length, which is represented by the cube root of the coordinate given by the specific point. Case studies have been also discussed to prove the optimal solutions derived by the proposed formula.

• The Journal of the Acoustical Society of Korea
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• 제16권2E호
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• pp.47-54
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• 1997

This paper presents two results on intersymbol interferences in baseband digital communication over an additive white Gaussian noise channel-the interferences due to mismatched square-root raised-cosine filters, in which the filters have different roll-off factors, and / or due to sampling-time jitter. The result for the mismatched filters is that even the jitter-free sampling causes intersymbol interference and it is negligibly small for a wide range of signal-to-noise ratio up to 10dB, for the roll-off factor ranging from 0.2 to 0.5, the mismatch loss being within 0.1dB from the optimum at around 10-6 .For jitter interference an approximation formula for the bit error probability is derived in case of the matched filters, which shows how the roll-off factors and the amount of jitter affect the system performance. The formula is reasonably accurate.

• 대한한의학방제학회지
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• 제10권2호
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• pp.251-260
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• 2002

The application of Shinkihuan umder the combination of configuration, color, pulse and symptoms leads to the following conclusions: 1. Shinkihuan is applied to the diseases related with lung, kidney and the spine: difficult urination of old people, shortness of breath, hematuria, loss of voice, distorted vision, deafness of deficiency, hemorrhoids, thirst, carbuncle, suppurative infection, children's retardation of walking and noma, etc... 2. The effect of Shinkihuan is as follows. It nourishes the lung, replenishes the kidney fluid, relieves the phlegm, tranquilizes fever due to deficiency of blood and reinforces the liver. 3. Shinkihuan is appropriate for the persons with the following characteristics in configuration: male, tall, thin, dam-typed, inverted-triangular, prominent nosed and dry.

• 대한전기학회논문지
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• 제33권6호
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• pp.232-240
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• 1984

이 논문은 전력계통에서의 상정사고 해석과 상정사고 대책에 관한 감도 행열에 관해 새로운 앨고리즘을 제시 하였다. 이 앨고리즘은 다른 일방적인 상정사고 해석 앨고리즘에 비해 선로사고나 모선사고시 실재상황에서 일어나는 모선전력 변화를 고려하여 개선된 AC 조류 계산법을 사용하여 정확한 조류변화를 얻었고 계산시간을 단축했다. 이 앨고리즘을 워어드헤일 5모선 계통과 IEEE의 24모선 계통에 적용하여 만족할만한 결과를 얻었다.

• Journal of Magnetics
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• 제6권2호
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• pp.66-69
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• 2001

The actual magnetic induction waveform of cores in electrical machines is not sinusoidal i.e. higher harmonics are always included. Thus the core loss in actual electrical machines is different from the core loss which is measured by the standard method, because the waveform of magnetic induction should be sinusoidal in the standard testing method. Core loss analysis under higher harmonic induction is always important in electric machine design. In this works we measured the core loss when a hysteresis loop has only one period of an ac minor loop of higher harmonic frequency, depending on the position of the ac minor loop of relative to the fundamental harmonic frequency. From this experiment, the core loss P(B/sub 0/f/sub 0/, B/sub h/, nf/sub 0/)) under a higher harmonic magnetic induction B/sub h/ could be expressed by the linear combination the core loss at fundamental harmonic frequency P/sub c/(B/sub 0/, f/sub 0/), the core loss of ac minor loop at zero induction region of the major hysteresis loop P/sub cL/ (B/sub h/, nf/sub 0/), and the core loss of an ac minor loop in the high induction region of the major hysteresis loop P/sub cH/ (B/sub h/, nf/sub 0/) i.e., P/sub c/, (B/sub 0/, f/sub 0/, B/sub h/, nf/sub 0/)=P/sub c/ (B/sub 0/, f/sub 0/,)+(n-1)[k₁(B/sub 0/) P/sub cL/ (B/sub h/, nf/sub 0/)+(1-k₁(B/sub 0/)) P/sub cH/ (B/sub h/, nf/sub 0/)]. This will be useful formula for electrical machine designers and one of effective methods to predict core loss including higher harmonic induction.