• Journal of Electrical Engineering and Technology
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• 제10권4호
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• pp.1527-1539
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• 2015

In this paper the hardware implementation of the direct torque control based on the fuzzy logic technique of induction motor on the Field-Programmable Gate Array (FPGA) is presented. Due to its complexity, the fuzzy logic technique implemented on a digital system like the DSP (Digital Signal Processor) and microcontroller is characterized by a calculating delay. This delay is due to the processing speed which depends on the system complexity. The limitation of these solutions is inevitable. To solve this problem, an alternative digital solution is used, based on the FPGA, which is characterized by a fast processing speed, to take the advantage of the performances of the fuzzy logic technique in spite of its complex computation. The Conventional Direct Torque Control (CDTC) of the induction machine faces problems, like the high stator flux, electromagnetic torque ripples, and stator current distortions. To overcome the CDTC problems many methods are used such as the space vector modulation which is sensitive to the parameters variations of the machine, the increase in the switches inverter number which increases the cost of the inverter, and the artificial intelligence. In this paper an intelligent technique based on the fuzzy logic is used because it is allows controlling the systems without knowing the mathematical model. Also, we use a new method based on the Xilinx system generator for the hardware implementation of Direct Torque Fuzzy Control (DTFC) on the FPGA. The simulation results of the DTFC are compared to those of the CDTC. The comparison results illustrate the reduction in the torque and stator flux ripples of the DTFC and show the Xilinx Virtex V FPGA performances in terms of execution time.

• Journal of Microbiology and Biotechnology
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• 제19권10호
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• pp.1191-1196
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• 2009

The production of Streptomyces griseus trypsin (SGT) by S. griseus IFO13350 transformed with the expression vector pWHM3-TR1R2, containing sprT encoding SGT and the two positive regulatory genes sgtR1 and sgtR2, was investigated in various media. Cultivation in Ferm-0 gave 1.4 times more trypsin activity than in C5/L medium. In addition, replacement of 2% glucose and 1% skim milk in Ferm-0 with 2% dextrin and 1% tryptone (designated Ferm-II) enhanced trypsin activity 4.1-fold. To simplify the purification process, the supernatant from the S. griseus transformant cultured in Ferm-II medium was fractionated with ammonium sulfate (25-55%), then subjected to Hitrap Benzamidine FF affinity column chromatography. The specific activity of SGT purified by one-step chromatography was 69,550 unit/mg protein and the overall purification yield was above 8%, indicating that this method is more effective than those previously reported. Purified SGT was most active at pH 8.0 and $50^{\circ}C$, and it maintained activity between pH 7.0 and 9.0 and at temperatures up to $70^{\circ}C$. These enzymatic properties are very similar to those of authentic eukaryotic trypsin purified from bovine pancreas.

• 대한수학회지
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• 제53권3호
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• pp.709-723
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• 2016

Let C[0, t] denote a generalized Wiener space, the space of real-valued continuous functions on the interval [0, t] and define a random vector $Z_n:C[0,t]{\rightarrow}{\mathbb{R}}^n$ by $Zn(x)=(\int_{0}^{t_1}h(s)dx(s),{\cdots},\int_{0}^{t_n}h(s)dx(s))$, where 0 < $t_1$ < ${\cdots}$ < $t_n$ < t is a partition of [0, t] and $h{\in}L_2[0,t]$ with $h{\neq}0$ a.e. In this paper we will introduce a simple formula for a generalized conditional Wiener integral on C[0, t] with the conditioning function $Z_n$ and then evaluate the generalized analytic conditional Wiener and Feynman integrals of the cylinder function $F(x)=f(\int_{0}^{t}e(s)dx(s))$ for $x{\in}C[0,t]$, where $f{\in}L_p(\mathbb{R})(1{\leq}p{\leq}{\infty})$ and e is a unit element in $L_2[0,t]$. Finally we express the generalized analytic conditional Feynman integral of F as two kinds of limits of non-conditional generalized Wiener integrals of polygonal functions and of cylinder functions using a change of scale transformation for which a normal density is the kernel. The choice of a complete orthonormal subset of $L_2[0,t]$ used in the transformation is independent of e and the conditioning function $Z_n$ does not contain the present positions of the generalized Wiener paths.

• 통상정보연구
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• 제19권2호
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• pp.65-84
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• 2017

본 연구에서는 몽골 및 중앙아시아 5개국(카자흐스탄, 우즈베키스탄, 키르기스스탄, 타자가스탄, 투르크메니스탄)의 경제발전에 외국인직접투자(FDI)와 무역(TRADE) 등의 변수들이 어떠한 영향을 미쳤는지를 실증 분석을 통해 확인하고자 하였다. 1995년~2015년까지 자료를 기반으로 실증분석 한 결과 카자흐스탄과 투르크메니스탄을 제외한 나머지 국가들의 경제성장에 FDI가 영향을 미친 것으로 확인되었고, 무역의 경우 모든 국가들에게 통계적으로 유의 하지 못한 것으로 나타났다. 이러한 실증분석 결과를 바탕으로 우리가 알 수 있는 것은 개발도상국가의 경제성장을 위해서는 무역도 중요하지만 본질적인 문제라 할 수 있는 경제의 취약성을 극복하기 위해서는 해외직접투자가 필수적임을 알 수 있다. 특히 내륙국 혹은 접경국가와의 교통 및 물류망에 대한 정부의 적극적 태도가 필요하며, 성숙되지 못한 시장경제로 인한 교역 및 투자의 제약성을 극복할 수 있는 기반을 조성하는 정책실행이 중요하다는 시사점을 제시할 수 있다.

• 한국항공우주학회지
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• 제45권9호
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• pp.734-745
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• 2017

달 착륙선의 항법 시스템은 자율 정밀 항법 성능을 확보하기 위해 관성측정기와 별추적기, 고도계, 속도계, 지형상대항법 카메라 등 다양한 항법용 전장부품으로 구성되는데 착륙선의 착륙 시나리오와 임무 요구 성능에 따라 적합한 성능의 항법용 전장부품 선정이 필요하다. 본 논문에서는 달 착륙선에 요구되는 항법용 전장부품의 사양을 공분산해석을 통해 분석하였다. 77차 상태변수로 구성되는 기준 시스템 오차모델과 센서의 측정모델을 정의하고 착륙선의 임무 요구 성능은 90m($3{\sigma}$) 착륙 위치 정확도를 요구하는 정밀탐사 임무와 6km($3{\sigma}$)의 착륙 오차가 허용되는 영역탐사 임무로 구분하였다. 자율항법 시작 시점에 따라 PDI(Powered descent initiation)와 DOI(Deorbit initiation) 시나리오로 나누고 항법용 전장부품의 조합과 착륙 시나리오에 따른 성능 분석을 통해 가상의 임무 요구 성능을 만족하기 위한 항법 시스템의 요구사양을 도출하였다.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
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• pp.111-111
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• 2001

목적： To evaluate the feasibility of the event-related functional MR study using power grip studying the hand motor system 대상 및 방법： Event-related functional MRI was performed on a 1.5T MR unit in seven norm volunteers (man=7, right-handedness=2, left-handedness=5, mean age： 25 years). A single-shot GRE-EPI sequence (TR/TE/flip angle： 1000ms/40ms/90, FOV = 240 mm matrix= 64$\times$64, slice thickness/gap = 5mm/0mm, 7 true axial slices) was used for functiona MR images. A flow-sensitive conventional gradient echo sequence (TR/TE/flip angl 50ms/4ms/60) was used for high-resolution anatomical images. To minimize the gross hea motion, neck-holders (MJ-200, USA) were used. A series of MR images were obtained in axial planes covering motor areas. To exclude motion-corrupted images, all MR images wer surveyed in a movie procedure and evaluated using the estimation of center of mass of ima signal intensities. Power grip task consisted of the powerful grip of all right fingers and hand movement ta used very fast right finger tapping at a speed of 3 per 1 second. All tasks were visual-guid by LCD projector (SHARP, Japan). Two tasks consisted of 134 phases including 7 activatio and 8 rest periods. Active stimulations were performed during 2 seconds and rest period were 15 seconds and total scan time per one task was 2 min 14 sec. Statistical maps we obtained using cross-correlation method. Reference vector was time-shifted by 4 seconds an Gaussian convolution with a FWHM of 4 seconds was applied to it. The threshold in p val for the activation sites was set to be 0.001. All mapping procedures were peformed usin homemade program an IDL (Research Systems Inc., USA) platform. We evaluated the activation patterns of the motor system of power grip compared to hand movement in t event-related functional MRI.

• 농업과학연구
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• 제44권2호
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• pp.145-180
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• 2017

Alternanthera mosaic virus (AltMV) is a member of the genus Potexvirus which has been known for less than twenty years, and has been detected in Australasia, Europe, North and South America, and Asia. The natural host range to date includes species in at least twenty-four taxonomically diverse plant families, with species in at least four other families known to be infected experimentally. AltMV has been shown to differ from Potato virus X (PVX), the type member of the genus Potexvirus, in a number of ways, including the subcellular localization of the Triple Gene Block 3 (TGB3) protein and apparent absence of interactions between TGB3 and TGB2. Differences between AltMV variants have allowed identification of viral determinants of pathogenicity, and identification of residues involved in interactions with host proteins. Infectious clones of AltMV differing significantly in symptom severity and efficiency of RNA silencing suppression have been produced, suitable either for high level protein expression (with efficient RNA silencing suppression) or for Virus-Induced Gene Silencing (VIGS; with weaker RNA silencing suppression), demonstrating a range of utility not available with most other plant viral vectors. The difference in silencing suppression efficiency was shown to be due to a single amino acid residue substitution in TGB1, and to differences in subcellular localization of TGB1 to the nucleus and nucleolus. The current state of knowledge of AltMV biology, including host range, strain differentiation, host interactions, and utility as a plant viral vector for both protein expression and VIGS are summarized.

• 산업경영시스템학회지
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• 제39권1호
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• pp.25-30
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• 2016

It is critical to forecast the maximum daily and monthly demand for power with as little error as possible for our industry and national economy. In general, long-term forecasting of power demand has been studied from both the consumer's perspective and an econometrics model in the form of a generalized linear model with predictors. Time series techniques are used for short-term forecasting with no predictors as predictors must be predicted prior to forecasting response variables and containing estimation errors during this process is inevitable. In previous researches, seasonal exponential smoothing method, SARMA (Seasonal Auto Regressive Moving Average) with consideration to weekly pattern Neuron-Fuzzy model, SVR (Support Vector Regression) model with predictors explored through machine learning, and K-means clustering technique in the various approaches have been applied to short-term power supply forecasting. In this paper, SARMA and intervention model are fitted to forecast the maximum power load daily, weekly, and monthly by using the empirical data from 2011 through 2013. $ARMA(2,\;1,\;2)(1,\;1,\;1)_7$ and $ARMA(0,\;1,\;1)(1,\;1,\;0)_{12}$ are fitted respectively to the daily and monthly power demand, but the weekly power demand is not fitted by AREA because of unit root series. In our fitted intervention model, the factors of long holidays, summer and winter are significant in the form of indicator function. The SARMA with MAPE (Mean Absolute Percentage Error) of 2.45% and intervention model with MAPE of 2.44% are more efficient than the present seasonal exponential smoothing with MAPE of about 4%. Although the dynamic repression model with the predictors of humidity, temperature, and seasonal dummies was applied to foretaste the daily power demand, it lead to a high MAPE of 3.5% even though it has estimation error of predictors.

• 대한수학교육학회지:학교수학
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• 제13권3호
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• pp.447-468
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• 2011

고등학교 수학교과과정에서 이차곡선에 관련된 단원의 지도는 다른 어떤 단원보다도 연결성이 고려된 지도가 필요한 단원이다. 다시 말해 대수적 접근 방식과 기하적 접근 방식이 동시에 병렬적으로 지도되어야 한다. 특히 대수적 조작력이 미흡한 하위권 학생들에게는 이차곡선에 대한 성질을 역동적으로 표현하는 시각적 표상을 심어주는 기하적 접근 방식이 더욱 중요하다. 이를 위하여 본 연구는 이차곡선의 지도에 있어서 GeoGebra에 기반한 역동적인 시각적 표상의 중요성을 제안하고자 현행 고등학교 '기하와 벡터' 10종의 교과서와 익힘책의 이차곡선 단원 중 포물선에 관련된 부분을 분석하여 시각적 표상을 극대화할 수 있는 지도 방안을 제안하는 실험적 수업을 진행하고 학생들의 표상의 변화를 분석하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권9호
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• pp.1363-1370
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• 2016

Rennet, a complex of enzymes found in the stomachs of ruminants, is an important component for cheese production. In our study, we described that yak chymosin gene recombinant Pichia pastoris strain could serve as a novel source for rennet production. Yaks total RNA was extracted from the abomasum of an unweaned yak. The yak preprochymosin, prochymosin, and chymosin genes from total RNA were isolated using gene specific primers based on cattle chymosin gene sequence respectively and analyzed their expression pattern byreal time-polymerase chain reaction. The result showed that the chymosin gene expression level of the sucking yaks was 11.45 times higher than one of adult yaks and yak chymosin belongs to Bovidae family in phylogenetic analysis. To express each, the preprochymosin, prochymosin, and chymosin genes were ligated into the expression vector $pPICZ{\alpha}A$, respectively, and were expressed in Pichia pastoris X33. The results showed that all the recombinant clones of P. pastoris containing the preprochymosin, prochymosin or chymosin genes could produce the active form of recombinant chymosin into the culture supernatant. Heterologous expressed prochymosin (14.55 Soxhlet unit/mL) had the highest enzyme activity of the three expressed chymosin enzymes. Therefore, we suggest that the yak chymosin gene recombinant Pichia pastoris strain could provide an alternative source of rennet production.