• Journal of applied mathematics & informatics
• /
• 제31권3_4호
• /
• pp.379-383
• /
• 2013

In this paper, we introduce more general concepts of regularity and S-unitality, that is, ${\pi}$-regularity and ${\pi}S$-unitality and then give some examples in near-rings, also investigate their characterization and proper-ties.

• 한국동물위생학회지
• /
• 제40권3호
• /
• pp.201-208
• /
• 2017

소에 있어서 BVDV는 반추류에서 중대한 감염을 야기하여 번식장애, 설사 및 유량감소를 야기하여 농가에 막대한 피해를 야기하고 있다. 특히 지속감염우의 확인과 도태는 농가 내 감염원을 제거하는 중요한 일이나 아직까지 PI개체의 바이러스의 감염과 전파에 관한 연구는 미진한 것으로 추정된다. 본 연구에서는 도입된 수컷에서 PI를 확인하였으며 전혈 검사를 실시 하면, PI 혈액 성상에서 림프구가 낮게 관찰되며 전체 WBC의 수는 정상범위에 속하나 낮게 나타나는 것을 알 수 있었다. PI 수컷에서 생산된 정액은 정자 수가 매우 낮으며, 신선 정액의 생존성도 불량한 것으로 조사되었다. 정자 기형율 또한 증가되었으며 특히 공포와 중편부의 소적을 가진 기형정자의 비율이 높았다. PI수컷은 나이가 들수록 정액 성상이 불량하여 불임화되었고 이는 BVDV가 정소의 정자 생산능력을 낮추어 사출된 정액내 정자수 감소 현상을 야기한다는 것을 알 수 있었다. 그럼에도 불구하고 확인된 PI 개체에 의한 전체군의 감염 현상은 관찰할 수 없었는데, 이는 적절한 백신 프로그램에 의하여 PI에 의한 간접적인 전파의 위험성이 낮다고 판단된다.

• 대한화학회지
• /
• 제26권2호
• /
• pp.65-72
• /
• 1982

여러 형태의(n${\pi}$/m) 및 (n-${\sigma}^*$) 구조가 에너지에 미치는 구조적인 기여를 살펴보기 위하여 n-프로필아민, n-프로필아민 라디칼, trans-및 cis-에틸렌 디아민에 대한 STO-3G 수준의 계산을 수행하였다. 그 결과 (5${\pi}$/5)구조가 (4${\pi}$/4)구조는 각각 인력 및 반발의 비결합 상호작용을 나타내었으며 서로 부가관계를 가짐을 알았다. anti(n-${\sigma}^*$) 구조는 syn(n-${\sigma}^*$)구조보다 강한 hyperconjugation효과를 보이지만 anti(n-${\sigma}^*$)구조에서 강한 핵간 반발력을 가지기 때문에 결과적으로 불안정한 겉보기 효과를 나타내었다. 더우기 안정화${\pi}$ -비결합 (5${\pi}$/5)구조는 anti(${\pi}$-${\sigma}^*$)구조를, 불안정화 ${\pi}$-비결합(4${\pi}$/4)구조는 syn(n-${\sigma}^*$)구조를 수반하며 상호 보강적으로 작용함을 알았다. 또한 이러한 상호 보강성이 일반적인 성질임을 알았다. 끝으로 말단의 고립 전자쌍에 의한 through-bond 상호작용을 논의하였으며 이러한 상호작용으로 에너지 준위가 $n_+ = \frac{1}{\sqrt{2}}(n_1\;+\;n_2)$와 $n_-\;=\;\frac{1}{\sqrt{2}}(n_1\;-\;n_2)$로 갈라지는데 이때 고립 전자쌍의 간단한 overlap pattern으로 n_준위가 안정한 준위임을 알았다.

• 동의생리병리학회지
• /
• 제25권6호
• /
• pp.1113-1118
• /
• 2011

In this paper, when a physician make a diagnosis of the pattern identification (PI) in Korean stroke patients, the development methods of the PI classification function is considered by diagnostic questionnaire of the PI for stroke patients. Clinical data collected from 1,502 stroke patients who was identically diagnosed for the PI subtypes diagnosed by two physicians with more than 3 years experiences in 13 oriental medical hospitals. In order to develop the classification function into PI using Korean Stroke Syndrome Differentiation Standard was consist of the 44 items (Fire heat(19), Qi deficiency(11), Yin deficiency(7), Dampness-phlegm(7)). Using the 44 items, we took diagnostic and prediction accuracy rate through of discriminant model. The overall diagnostic and prediction accuracy rate of the PI subtypes for discriminant model was 74.37%, 70.88% respectively.

• 분석과학
• /
• 제14권4호
• /
• pp.331-339
• /
• 2001

감귤류와 한국산 청피에 함유된 methoxylated flavonoids (sinenstin, nobiletin, tangeretin)를 HPLC, mass 그리고 NMR로 분리하고 분석하였다. Methoxylated flavonoids는 Chung-pi(I)과 Chung-pi(II)에 가장 풍부하게 함유되었다. 한국산 밀감에서 얻어진 Chung-pi(I), (II)의 methoxylated flavonoids 함유량은 밀감성숙도에 따라 증가하였으며, 10월 중순이후에는 서서히 감소하였다.

• 한국생산제조학회지
• /
• 제21권4호
• /
• pp.651-657
• /
• 2012

In many control fields high position performance is essentially required in reducing the over-shoot phenomena which is produced by improving the quick response in starting and in minimizing the variation of the response characteristic on disturbance and load variation In this paper, the design method for a position control is suggested for constructing the PI-PD controllers by using an internal PD feedback loop in PI and PD control system. Applying this method to the position control system used a DC servo motor as a driver, the transfer PI and PD controllers are designed simultaneously and the coefficients of these controllers are determined by using the transfer function of a plant and a proportional coefficient from mathematical technique. From the result of computer simulation in PI-PD control system by applying this control technique, we can verify the usefulness of this method in rejecting of over-shoot of starting, compensating of response variation on the load variation, and shorting the settling time.

• 한국의류학회지
• /
• 제36권10호
• /
• pp.1117-1124
• /
• 2012

This study was a preliminary study to investigate the influence of surface morphology and characteristics on the self-cleaning of substrates. PI film was treated by $O_2$ plasma to modify the surface; in addition, AFM and Fe-SEM were employed to examine the morphological changes induced on a PI film treated by $O_2$ plasma and surface energies calculated from measured contact angles between several solutions and PI film based on the geometric mean and a Lewis acid base method. The surface roughness of PI film treated by $O_2$ plasma increased with the duration of the $O_2$ plasma on PI film due to the increased surface etching. The contact angle of film treated by $O_2$ plasma decreased with the increased treatment time in water and surfactant solution; in addition, the surface energy increased with the increased treatment times largely attributed to the increased portion on the polar surface energy of PI film. The coefficient of the correlation between surface roughness and surface polarity such as contact angle and surface energy was below 0.35; however, it was over 0.99 for the contact angle and surface energy.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1992년도 하계학술대회 논문집 B
• /
• pp.1225-1227
• /
• 1992

This paper presents a study on the variable structure PI(proportional and integrate) control which is insensible to the variation of parameters or external disturbance for driving DC motor. In the presented variable structure PI control (VSPIC), the sliding mode control was used at the below of 4000 rpm and PI control also used at the above of 4000 rpm with no load. In other way, the PI control was used at the below of 4000 rpm and the sliding mode control at the above of 4000 rpm with some loading, and then the output waveform following the variation of load was measured. intel 8031 microcomputer unit and IBM PC was combined to form the full system and the speed control was performed with it. The experimental result of the fast response to speed was more improve than it was open loop state. For load varing, the sliding mode insensible to external disturbance was applied and the improved response was obtained.

• Journal of Life Science
• /
• 제9권1호
• /
• pp.40-44
• /
• 1999

Glutathione S-transferase (GST) is a multifunctional protein that catalyzes the catalyzes the conjugation of glutathione with electrophilic compounds. It exists in a variety of isoenzy-matic froms with a wide range of substrate specificity and plays a pivotal role in detoxification of various drugs. In order to elucidate the GST-${\pi}$'s involvement of multidrug resistance (MDR) in drug-resistant tumor cell lines, we determined GST-${\pi}$ content by "1 step sandwich method". Consequently, adriamycin resistant cells of MCF-7 (MCF-7/ADM) have 7-fold increase of GST-${\pi}$ content than that of MCF-7 cells, while its {TEX}$IC_{50}${/TEX} was 116-fold greater than parent cell line. By northrn blotting, we compared whether MCF-7/ADM cells express GST-${\pi}$ mRNA. The GST-${\pi}$ mRNA expression in these cells was not inducible, but constitutive when treated for 24 h with a concentration of 0, 20, 200, and 2000 nM of adriamycin, respectively. Taken together, these results suggest that GST-${\pi}$ may not be directly associated with multidrug resistance in these human cancer cell lines.ell lines.

• Journal of Electrical Engineering and Technology
• /
• 제12권5호
• /
• pp.1821-1834
• /
• 2017

Medium voltage control applications due to obtain better output voltage and reduced electro-magnetic interference multi level inverter is used. In closed loop control with inverter, the PI controller does not operate satisfactorily when the operating point changes. This paper presents the performance of Co-Efficient diagram PI controller based indirect vector controlled induction motor drive fed from three-level inverter under different operating conditions (dynamic and steady state). The proposed Co-Efficient diagram PI controller based three level inverter significantly reduces the torque ripple compared to that of conventional PI controller. The performance of the indirect vector controlled induction motor drive has been simulated at different operating conditions. For three-level inverter control, a simplified space vector modulation technique is implemented, which reduces the coordinate transformations complications in the algorithms. The performance parameters, torque ripple contents and THD of induction motor drive with three-level inverter is compared under different operating conditions using CDM-PI and conventional PI controllers.