• Title/Summary/Keyword: Unit Vector

Search Result 445, Processing Time 0.023 seconds

Design and Implementation of Direct Torque Control Based on an Intelligent Technique of Induction Motor on FPGA

  • Krim, Saber;Gdaim, Soufien;Mtibaa, Abdellatif;Mimouni, Mohamed Faouzi
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.4
    • /
    • pp.1527-1539
    • /
    • 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.

Medium Optimization and Application of Affinity Column Chromatography for Trypsin Production from Recombinant Streptomyces griseus

  • Chi, Won-Jae;Song, Ju-Hyun;Oh, Eun-A.;Park, Seong-Whan;Chang, Yong-Keun;Kim, Eung-Soo;Hong, Soon-Kwang
    • Journal of Microbiology and Biotechnology
    • /
    • v.19 no.10
    • /
    • pp.1191-1196
    • /
    • 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.

SCALE TRANSFORMATIONS FOR PRESENT POSITION-INDEPENDENT CONDITIONAL EXPECTATIONS

  • Cho, Dong Hyun
    • Journal of the Korean Mathematical Society
    • /
    • v.53 no.3
    • /
    • pp.709-723
    • /
    • 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.

The Impact of FDI on Economic Growth in Mongolia and Central Asia (외국인직접투자가 몽골 및 중앙아시아 경제발전에 미치는 영향 분석)

  • Narantsetseg, Narantsetseg;Park, Hyun Hee
    • International Commerce and Information Review
    • /
    • v.19 no.2
    • /
    • pp.65-84
    • /
    • 2017
  • This paper attempts to investigate FDI Trade have been viewed a power affecting economic growth in Mongolia and five Central Asian countries(Kazakhstan, Uzbekistan, Kyrgyzstan, Kazakhstan and Turkmenistan) directly and indirectly using the Vector Error Correction Model. The results of empirical analysis based on data from 1995 to 2015 confirmed that FDI had a significant impact on economic growth in the rest of countries expect Kazakhstan and Turkmenistan, and Trade was not statistically significant for all countries. Accordingly we've come to below conclusion in consideration of the results of the statistics survey. It is urgently required to implement the policies on promoting foreign investment at first in order to recover economic decline though the international trading is considered important in developing the economics of developing countries. Especially, the landlocked countries, namely the countries having same border should focus on promoting the development of transport and freight forwarding systems between the countries, implementing the policies on trade relationships and foreign direct investments throughout the nation in consideration of the low- level of market economic conditions.

  • PDF

Requirement Analysis of Navigation System for Lunar Lander According to Mission Conditions (임무조건에 따른 달 착륙선 항법시스템 요구성능 분석)

  • Park, Young Bum;Park, Chan Gook;Kwon, Jae Wook;Rew, Dong Young
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.45 no.9
    • /
    • pp.734-745
    • /
    • 2017
  • The navigation system of lunar lander are composed of various navigation sensors which have a complementary characteristics such as inertial measurement unit, star tracker, altimeter, velocimeter, and camera for terrain relative navigation to achieve the precision and autonomous navigation capability. The required performance of sensors has to be determined according to the landing scenario and mission requirement. In this paper, the specifications of navigation sensors are investigated through covariance analysis. The reference error model with 77 state vector and measurement model are derived for covariance analysis. The mission requirement is categorized as precision exploration with 90m($3{\sigma}$ ) landing accuracy and area exploration with 6km($3{\sigma}$ ), and the landing scenario is divided into PDI(Powered descent initiation) and DOI(Deorbit initiation) scenario according to the beginning of autonomous navigation. The required specifications of the navigation sensors are derived by analyzing the performance according to the sensor combination and landing scenario.

The Feasibility of Event-Related Functional Magnetic Resonance Imaging of Power Hand Grip Task for Studying the Motor System in Normal Volunteers; Comparison with Finger Tapping Task

  • Song, In-Chan;Chang, Kee-Hyun;Han, Moon-Hee
    • Proceedings of the KSMRM Conference
    • /
    • 2001.11a
    • /
    • pp.111-111
    • /
    • 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.

  • PDF

Alternanthera mosaic virus - an alternative 'model' potexvirus of broad relevance

  • Hammond, John;Kim, Ik-Hyun;Lim, Hyoun-Sub
    • Korean Journal of Agricultural Science
    • /
    • v.44 no.2
    • /
    • pp.145-180
    • /
    • 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.

Short-term Forecasting of Power Demand based on AREA (AREA 활용 전력수요 단기 예측)

  • Kwon, S.H.;Oh, H.S.
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.39 no.1
    • /
    • pp.25-30
    • /
    • 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.

Instruction method for Quadratic Curve Based on Dynamic Visual Representation by applying GeoGebra (GeoGebra를 활용한 역동적인 시각적 표상에 기반한 이차곡선 지도 방안)

  • Yang, Seong-Hyun;Kang, Ok-Ki
    • School Mathematics
    • /
    • v.13 no.3
    • /
    • pp.447-468
    • /
    • 2011
  • For the instruction of units dealing with the conic section, the most important factor that we need to consider is the connections. In other words, the algebraic approach and the geometric approach should be instructed in parallel at the same time. In particular, for the students of low proficiency who are not good at algebraic operation, the geometric approach that employs visual representation, expressing the conic section's characteristic in a dynamic manner, is an important and effective method. For this, during this research, to suggest the importance of dynamic visual representation based on GeoGebra in teaching Quadratic Curve, we taught an experimental class that suggests the instruction method which maximizes the visual representation and analyzed changes in the representation of students by analyzing the part related to the unit of a parabola from units dealing with a conic section in the "Geometry and Vector" textbook and activity book.

  • PDF

Cloning and Expression of Yak Active Chymosin in Pichia pastoris

  • Luo, Fan;Jiang, Wei Hua;Yang, Yuan Xiao;Li, Jiang;Jiang, Ming Feng
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.29 no.9
    • /
    • pp.1363-1370
    • /
    • 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.