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MYLLER CONFIGURATIONS IN FINSLER SPACES. APPLICATIONS TO THE STUDY OF SUBSPACES AND OF TORSE FORMING VECTOR FIELDS

  • Constantinescu, Oana
    • Journal of the Korean Mathematical Society
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    • v.45 no.5
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    • pp.1443-1482
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    • 2008
  • In this paper we define a Myller configuration in a Finsler space and use some special configurations to obtain results about Finsler subspaces. Let $F^{n}$ = (M,F) be a Finsler space, with M a real, differentiable manifold of dimension n. Using the pull back bundle $({\pi}^{*}TM,\tilde{\pi},\widetilde{TM})$ of the tangent bundle $(TM,{\pi},M)$ by the mapping $\tilde{\pi}={\pi}/TM$ and the Cartan Finsler connection of a Finsler space, we obtain an orthonormal frame of sections of ${\pi}^{*}TM$ along a regular curve in $\widetilde{TM}$ and a system of invariants, geometrically associated to the Myller configuration. The fundamental equations are written in a very simple form and we prove a fundamental theorem. Important lines in a Finsler subspace are defined like special lines in a Myller configuration, geometrically associated to the subspace: auto parallels, lines of curvature, asymptotes. Torse forming vector fields with respect to the Cartan Finsler connection are characterized by means of the invariants of the Frenet frame of a versor field along a curve, and the new notion of torse forming vector fields in the sense of Myller is introduced. The particular cases of concurrence and parallelism in the sense of Myller are completely studied, for vector fields from the distribution $T^m$ of the Myller configuration and also from the normal distribution $T^p$.

A Study on the Transient Phenomenon Analysis of Ship Generator Synchronization (선박용 발전기 동기화시의 과도현상 해석에 관한 연구)

  • Oh, Sae-Gin;Kim, Jong-Su;Kim, Sung-Hwan;Lee, Sung-Gun;Jo, Sung-Kab
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.8
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    • pp.998-1004
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    • 2007
  • Connecting a synchronous generator to a power system is a dynamic process, requiring the coordinated operation of many components and systems. The goal is to connect the oncoming generator to the system smoothly i.e without causing any significant bumps, surges, or power swings, by closing the ACB when the oncoming generator matches the power system in voltage magnitude, phase angle, and frequency. If oncoming generator voltage is not matched to the power system voltage, reactive power will flow either into or out of the system at the instant of ACB closure. If this voltage difference is too great, the reactive power flow may result in high transient stresses that could damage the windings of the generator. Also, if oncoming generator frequency is not matched to the power system frequency, transient power will flow between generator and power system. If the frequency difference is too great, the transient power flow is reflected into the prime mover shaft, and this may result in excessive shaft or coupling stress. This paper tries to prove the necessity of correct synchronization for ship generators through a transient phenomenon analysis.

Electrical Breakdown Properties of Insulating Oils for oil-immersed transformer (유입변압기용 절연유의 절연파괴특성)

  • Lee, I.S.;Shin, H.T.;Lee, J.P.;Lee, S.W.;Hong, J.W.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.605-608
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    • 2001
  • With the intention of investigating the breakdown properties of oil-immersed transformer oils in temperature range of $20\sim100[^{\circ}C]$, we are made researches AC breakdown in the gap of $500\sim2500[{\mu}m]$. The classification for the physical properties of oil for oil-immersed transformer by FTIR and H-NMR experiments was confirmed to type of mineral oils. As the dependance of breakdown properties due to electrode gap length variation, breakdown voltage was found increasing according to the increase of gap, while dielectric strength was decreasing. As a result the characteristics for AC breakdown, It goes to prove that the breakdown voltage was increased to $90[^{\circ}C]$ but decreased over $90[^{\circ}C]$ in the temperature range. Also, breakdown voltage was found increasing in the increase of gap and the rising of temperature according to Weibull distribution.

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Secure Block Cipher Algorithm for DC and LC (DC와 LC에 안전한 SPN 구조 암호 알고리즘)

  • Choe, Eun-Hwa;Seo, Chang-Ho;Seong, Su-Hak;Ryu, Hui-Su;Jeon, Gil-Su
    • The KIPS Transactions:PartC
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    • v.9C no.4
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    • pp.445-452
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    • 2002
  • In this paper, we suggest the design of 128bit block cipher which is provable security based on mathematics theory. We have derived the 16$\times$16 matrix(i.e.,linear transformation) which is numerous active S-box, and we proved for DC and LC which prove method about security of SPN structure cipher algorithm. Also, the minimum number of active S-box, the maximum differential probabilities and the maximum linear probabilities in round function of 128bit block cipher algorithm which has an effect to DC and LC are derived.

Location-based System for Tracking Similar Trajectories Using Hybrid Method (하이브리드 기법을 이용한 LBS기반의 유사궤적 추적시스템)

  • Han, Kyoung-Bok;Kwon, Hoon;Lee, Hye-Sun;Kwak, Ho-Young
    • The Journal of the Korea Contents Association
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    • v.7 no.6
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    • pp.9-21
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    • 2007
  • In this paper, the hybrid methods are suggested, which use the direction angle information to present running trajectory and track the past locations through a small amount of vehicle's location information. In order to prove the effectiveness of the new technique suggested here, vehicle's location information are collected by running the vehicles moving objects under various conditions. Using the location informations and direction angle information collected with time intervals, the vehicl e's location information is abstracted, compared and analyzed. and I have proved that the suggested techniques are more effective by comparing them with others in various methods such as GPS TrackMaker, difference image techniques, consistency comparison, quantity comparison, vehicle's running distances and so on.

Study on the Sedative Effect and the Anticonvulsive Effect of Incenses in Aroma Therapy (향기요법(분향)이 진정 및 항경련에 미치는 실험적 연구)

  • Song Tae Won
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.3
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    • pp.567-571
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    • 2002
  • In order to prove the sedative, anticonvulsive effects of Incenses and to identify the effect of this medicine to cerebral glutamic acid and GABA density in experimental animal. we used Incense which was made of traditional herb medicines. We also examined what kind of material is to be involved in biosynthesis of these elements. In addition we experimented to find out synthesis of active GABA-T. Incenses were inhaled 8 hours a day for 4 weeks to mice. Finally we have following results. On the convulsion induced by pentylenetetrazole(PTZ), Incenses showed significant anticonvulsive effect. Density of glutamic acid in brain was significantly decreased. On the contrary, density of GABA was significantly increased. The Activity of GABA- T in brain was significantly reduced. The quantity of lipid peroxide in the brain was significantly decreased. Activity of xanthine oxidase and aldehyde oxidase were significantly reduced in brain. From the above results, we confirmed that Incenses decreased the density of glutamic acid, increased GABA density and decreased the activity of GABA- T in brain. For the convulsion which was induced by PTZ, Incenses showed significant anticonvulsive effect. With this we can recognize that Incenses had ability to control the quantity of lipid peroxide in brain. In the conclusion, Incenses has significant anticonvulsive effect, so I strongly recommend to prescribe Incenses to treat convulsive disorder like epilepsy.

Vision Inspection for Flexible Lens Assembly of Camera Phone (카메라 폰 렌즈 조립을 위한 비전 검사 방법들에 대한 연구)

  • Lee I.S.;Kim J.O.;Kang H.S.;Cho Y.J.;Lee G.B.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.631-632
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    • 2006
  • The assembly of camera lens modules fur the mobile phone has not been automated so far. They are still assembled manually because of high precision of all parts and hard-to-recognize lens by vision camera. In addition, the very short life cycle of the camera phone lens requires flexible and intelligent automation. This study proposes a fast and accurate identification system of the parts by distributing the camera for 4 degree of freedom assembly robot system. Single or multi-cameras can be installed according to the part's image capture and processing mode. It has an agile structure which enables adaptation with the minimal job change. The framework is proposed and the experimental result is shown to prove the effectiveness.

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A Study on the Measurement of Load Torque by the Field Coil Current in an Eddy Current Dynamometer (와전류 동력계에서 계자전류를 이용한 부하토크의 측정에 관한 연구)

  • Mun, Byung-Su;Lee, Eung-Suk;Lee, Hyung-Seok
    • Journal of the Korean Society for Precision Engineering
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    • v.18 no.10
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    • pp.84-92
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    • 2001
  • Commercial eddy current dynamometers control the torque of rotating body, power supply machine, with the field coil current being operated as a braking force. In this paper, we studied the relation between field coil current and torque load of eddy current dynamometer. By the torque measuring analysis of eddy current dynamometer it is linear relation between the brake force measured from a torque meter which is installed at the case of dynamometer and the multiplied shaft rpm by the squares of field coil current (N$\times$I$^2$). To prove the relation, it was experimented and showed that the torque operated by the rotating body can be measured with the shaft rpm and the field coil current of the eddy current dynamometer. This result shows a possibility that eddy current dynamometer can measure the torque of rotating body without a torque measuring device. such as load cell.

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Study of CMM base Information Technology company level estimation (CMM 기반 정보기술 업체 수준평가에 관한 연구)

  • Kim Tai-Dal
    • Journal of Internet Computing and Services
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    • v.5 no.1
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    • pp.33-39
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    • 2004
  • In this paper, so that government official in target extent of relevant shame capacitates CMM measuring achievement result by each process as quantitative because do standard, repeat and achieves gap analysis and estimation solidify knowledge management of information base enabling "Quality control, production management, cost control, integral management of knowledge", Solidify customer service through "high-quality, differentiation" of information. Establish administration and supervision item to reach 4 steps level in information ability measurement in formation to prove business efficiency through process optimization and improves formation maturity through voluntary effort of formation continuously. Suggested model who analyze and evaluates application in domestic SI specialty company.I specialty company.

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Effect of Edible Coatings Containing Soy Protein Isolate (SPI) on the Browning and Moisture Content of Cut Fruit and Vegetables

  • Shon, Jin-Han;Choi, Yong-Hwa
    • Journal of Applied Biological Chemistry
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    • v.54 no.3
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    • pp.190-196
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    • 2011
  • Effectiveness of edible coatings containing soy protein isolate (SPI), in reducing oxidative browning and moisture loss during storage ($4^{\circ}C$) of cut apples, potatoes, carrots, and onions was investigated. The SPI coatings were shown to have antioxidative activity. Furthermore, addition of carboxymethyl cellulose (CMC) to the formulations significantly improved its antioxidative activity. Oxidative discoloration, as determined by Commission Internationale De I'Eclairage (CIE) lightness ($L^*$), redness ($a^*$), and yellowness ($b^*$) color scale, was significantly reduced (p <0.05) by SPI coating treatments over a storage time of 120 min. Loss of lightness was reduced by SPI coatings with and without CMC. These respectively showed 4.03 and 3.71% change of $L^*$ value compared to 8.56% for control. Browning of the control in cut potatoes was significantly increased by 106.6% in contrast to 34.3 and 35.2% for SPI coatings with and without CMC, respectively. The $b^*$ values also reflected effectiveness of SPI. Moisture barrier effect was significantly better for the treatments, compared to the control. SPI coatings reduced moisture loss in apples and potatoes, respectively, by 21.3 and 29.6% over the control. Cut onions did not show any treatment effect both in terms of browning and moisture loss. SPI coatings prove to be good moisture barrier and antioxidative property.